Regional Pest Management Plan - Marlborough · 2017. 11. 16. · Regional Pest Management Plan...

PROPOSAL

IN ACCORDANCE WITH THE BIOSECURITY ACT 1993

November 2017

Regional Pest Management Plan

Regional Pest Management Plan Proposal

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Regional Pest Management Plan

Proposal

Record No: 1662674

23 November 2017

Prepared by: Jono Underwood

Biosecurity Coordinator Environmental Science & Monitoring Group

Marlborough District Council Seymour Square

PO Box 443 Blenheim 7240

Phone: 520 7400 Website: www.marlborough.govt.nz

http://www.marlborough.govt.nz/


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Table of Contents Table of Contents ...................................................................................................................................... iii Part One .................................................................................................................................................... 1 1. Introduction ................................................................................................................................... 1

1.1 Proposer ............................................................................................................................. 1 1.2 Purpose .............................................................................................................................. 1 1.3 Coverage ............................................................................................................................ 1 1.4 Duration .............................................................................................................................. 1 1.5 Consultation ....................................................................................................................... 3

2. Effects of the Plan’s Implementation ............................................................................................ 3 2.1 Economic wellbeing ............................................................................................................ 3 2.2 The environment ................................................................................................................ 4 2.3 Human health ..................................................................................................................... 4 2.4 The enjoyment of the natural environment......................................................................... 4 2.5 The relationship with Māori and their culture and their traditions and their ancestral

lands, waters, sites, wāhi tapu and taonga ........................................................................ 4 2.6 The marketing overseas of New Zealand products ........................................................... 4

3. Relationship with other pest management or pathway plans ....................................................... 5 4. Responsibilities and obligations ................................................................................................... 5

4.1 The management agency................................................................................................... 5 4.2 Compensation and disposal of receipts ............................................................................. 5 4.3 Affected parties .................................................................................................................. 5

5. Relationship with the National Policy Direction ............................................................................ 6 Part Two Proposed Programmes ...................................................................................................... 7 6. The subjects of this Proposal ................................................................................................................ 7

6.1 Pest management programmes - What you’ll find in this Proposal....................................... 8 7. Programmes ....................................................................................................................................... 10

7.1 African feather grass (Cenchrus macrourus) ................................................................... 10 7.2 Bathurst bur (Xanthium spinosum) ................................................................................... 16 7.3 Boneseed (Chrysanthemoides monilifera) ....................................................................... 22 7.4 Broom (Cytisus scoparius) ............................................................................................... 28 7.5 Brushtail possum (Trichosurus vulpecula) ....................................................................... 39 7.6 Bur daisy (Calotis lappulacea) ......................................................................................... 46 7.7 Cathedral bells (Cobaea scandens) ................................................................................. 51 7.8 Chilean needle grass (Nassella neesiana)....................................................................... 57 7.9 Chinese pennisetum (Pennisteum alpecuroides) ............................................................ 66 7.10 Climbing spindleberry (Celastrus orbiculatus).................................................................. 72 7.11 Contorta pine (Pinus contorta) ......................................................................................... 78 7.12 Corsican pine (Pinus nigra) .............................................................................................. 85 7.13 Cotton thistle (Onopordum acanthium) ............................................................................ 92 7.14 Eel grass (Vallisneria australis) ........................................................................................ 98 7.15 European larch (Larix decidua) ...................................................................................... 104


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7.16 Evergreen buckthorn (Rhamnus alaternus) ................................................................... 110 7.17 Giant needle grass (Austrostipa rudis) ........................................................................... 116 7.18 Gorse (Ulex europaeus) ................................................................................................. 122 7.19 Kangaroo grass (Themeda triandra) .............................................................................. 132 7.20 Madeira vine (Andredera cordifolia) ............................................................................... 142 7.21 Mediterranean fanworm (Sabella spallanzanii) .............................................................. 148 7.22 Moth plant (Araujia hortorum) ........................................................................................ 157 7.23 Mountain pine (Pinus mugo) .......................................................................................... 163 7.24 Nassella tussock (Nassella trichotoma) ......................................................................... 170 7.25 Parrots feather (Myriophyllum aquaticum) ..................................................................... 177 7.26 Purple loosestrife (Lythrum salicaria) ............................................................................. 182 7.27 Rabbits (Oryctolagus cuniculus) .................................................................................... 188 7.28 Reed sweet grass (Glyceria maxima) ............................................................................ 196 7.29 Rooks (Corvus frugilegus) .............................................................................................. 202 7.30 Rough horsetail (Equisetum hyemale) ............................................................................ 206 7.31 Saffron thistle (Carthamus lanatus) ................................................................................ 211 7.32 Scots pine (Pinus sylvestris) .......................................................................................... 217 7.33 Senegal tea (Gymnocoronis spilanthoides) ................................................................... 223 7.34 Spartina (Spartina anglica) ............................................................................................... 228 7.35 Tall wheat grass (Thinopyrum ponticum) ....................................................................... 235 7.36 Wallabies (Family Macropodidae) .................................................................................. 241 7.37 Western white pine (Pinus monticola) ............................................................................ 248 7.38 White-edged nightshade (Solanum marginatum) .......................................................... 255 7.39 Wilding conifers .............................................................................................................. 262 7.40 Willow-leaved hakea (Hakea salicifolia) ......................................................................... 271 7.41 Woolly nightshade (Solanum mauritianum) ................................................................... 278

8. Monitoring ................................................................................................................................. 283 8.1 Measuring against programme objectives ..................................................................... 283 8.2 Monitoring the management agency’s performance ...................................................... 284

9. Exemptions ............................................................................................................................... 284 Part Three Administrative provisions................................................................................................ 286 10. Powers conferred ..................................................................................................................... 286

10.1 Powers of Authorised Persons under Part 6 of the Act .................................................. 286 10.2 Powers under other sections of the Act ......................................................................... 286

11. Funding ..................................................................................................................................... 286 11.1 Introduction ..................................................................................................................... 286 11.2 Beneficiaries and exacerbators ...................................................................................... 287 11.3 Funding sources and reasons for funding ...................................................................... 287 11.4 Anticipated costs of implementing the Plan ................................................................... 291

Glossary ................................................................................................................................................ 293 Appendices ............................................................................................................................................ 296 Appendix 1 Wilding conifer Collaborative Wilding Conifer Programme Areas process .................... 296 Appendix 2 Economic analyses supporting analysis of benefits and costs .................................... 298


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1) Chilean needle grass - No RPMP .................................................................................. 298 2) Chilean needle grass - Sustained Control...................................................................... 300 3) Chilean needle grass - Eradication ................................................................................ 302 4) Kangaroo grass - No RPMP ........................................................................................... 306 5) Kangaroo grass - Sustained Control .............................................................................. 308 6) Kangaroo grass - Eradication ......................................................................................... 310 7) Mediterranean fanworm - No RPMP .............................................................................. 314 8) Mediterranean fanworm - Exclusion ............................................................................... 316 9) Nassella tussock - No RPMP ......................................................................................... 318 10) Nassella tussock - Sustained Control ............................................................................ 320

Appendix 3 Modified McLean Scale for assessing rabbit populations .............................................. 322 Appendix 4 List of brushtail possum-free islands .............................................................................. 323 Appendix 5 Process for regional biosecurity responses ................................................................... 324


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Part One

1. Introduction 1.1 Proposer The Marlborough District Council (Council) has a regional leadership role under section 12B of Biosecurity Act 1993 (the Act). As such, in accordance with section 100D of the Act, proposes to establish a Regional Pest Management Plan (the Plan) that replaces the current Plan that became operative on 17 December 2012.

The existing Plan was last reviewed as a whole, and became operative, on 2 July 2007. Because it was last reviewed more than 10 years previously, Council must initiate a review by making a Proposal. In addition, the assessment of consistency with the National Policy Direction (NPD) also demonstrated that a review is necessary to comply with requirement within that direction.

The first formal step is the making of this Proposal.

1.2 Purpose The purpose of the Proposal is to outline the framework to efficiently and effectively manage specified organisms in the Marlborough region.

A Regional Pest Management Plan is the major guiding mechanism for Council targeting specific organisms. However, it is not the only mechanism used by Council. Other services related to biosecurity are implemented by Council and guided by the Council’s overarching Biosecurity Strategy.

The Act has prerequisite criteria that must be met to justify such intervention using a Plan. This Proposal identifies programmes for organisms that, in the opinion and analysis undertaken by Council, meet those perquisite criteria. If Council is satisfied with proposed programmes through due process and a Plan is made, this would result in the organisms subject to the programmes being classified as pest under the Act.

Once operative, the Plan will empower Council to exercise the relevant advisory, service delivery and regulatory provisions available under the Act to deliver the specific objectives identified in Part Two: Pest Management.

The public can make submissions on the Proposal. Council will issue decisions after reviewing those submissions and hearing those who wish to be heard. Decisions can be appealed through the Environment Court by submitters only.

1.3 Coverage Unless otherwise stated in an individual pest programme, the Plan will operate within the administrative boundaries of the Marlborough district, including territorial waters, and covers a total area (land and sea) of 1,768,886 hectares.

1.4 Duration The proposed Plan will take effect on the date it becomes operative under section 77 of the Act. The Plan will be reviewed in accordance with section 100D of the Act, which outlines that a mandatory review must take place within 12 months of the Plan being in effect for a period 10 years.

Under the provisions of section 100D, minor reviews affecting part of the Plan can take place at any time.


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Figure 1: The Marlborough Region


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1.5 Consultation There has been no consultation conducted on this Proposal as a whole until the Council formally makes the Proposal under the Biosecurity Act 1993. After this first step, specific consultation will occur with iwi and a numerous of other parties. A public notification, submission and hearing process will also take place.

A large degree of ‘pre-consultation’ has occurred using preliminary material in the form of a Discussion Document and the supply of draft material to specific sector groups for feedback. The following ‘pre-consultation’ has occurred over the previous 2 year period:

• Release of a Discussion Document for public feedback in March 2016. This included directly making the recipient aware of the document with a request for feedback to:

- Ngati Apa Ki Te Ra To Trust

- Ngati Koata Trust

- Ngati Rarua Iwi Trust (BHE)

- Ngati Tama Ki Te Tau Ihu Trust

- Ngati Toa Rangatira Manawhenua Ki Te Tau Ihu Trust

- Te Atiawa o Te Waka-a-Maui Trust

- Te Runanga A Rangitane O Wairau

- Te Runanga O Kaikoura Inc

- Te Runanga O Ngati Kuia

- Te Runanga O Toa Rangatira Inc

- Toitu Te Whenua Te Runanga O Ngai Tahu

- 52 residents and ratepayer associations within Marlborough

- 328 land occupiers that are affected by current existing rules within under the current Plan

- 13 statutory bodies and neighbouring councils

- key primary industry bodies operating in Marlborough

• All feedback received (both during the formal process and subsequent feedback received) on the Discussion Document was acknowledged and used to formulate the Proposal, where appropriate.

• Direct discussion with community groups over programmes of interest and proposed provisions. These included:

- Marlborough Chilean Needle Grass Action Group

- Sounds Advisory Group (Council led forum in conjunction with community associations within the Marlborough Sounds)

- Rural Advisory Group

2. Effects of the Plan’s Implementation In the opinion of the Council, the Plan may have an effect on the following:

2.1 Economic wellbeing Numerous proposed programmes detail the effects that the subjects of the Proposal may have on production systems. This can be through competition with preferred pasture or aquaculture species, affecting the quality of livestock carcasses or interfering with the production chain in an adverse manner.


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The effective management of those subjects or preventing their establishment in Marlborough will have large positive benefits to the economic wellbeing of both individuals and the Marlborough economy at large.

Further detail on specific subjects can be found under the each proposed programme for the subjects.

2.2 The environment Numerous proposed programmes detail the effects that the subjects of the Proposal may have on the environment. More commonly, those subjects that are invasive weeds can have profound long term impacts on the health and integrity of ecosystems and their function. This can be via competition with native flora for nutrient, space and light or altering habitats in a way that no longer supports native fauna. Other subjects, such as an invasive marsupial (wallabies), would have more of a direct effect on the environment through the browsing of regenerating vegetation.

The effective management of those subjects or preventing their establishment in Marlborough will have significant positive benefits to Marlborough’s environment.

Further detail on specific subjects can be found under each proposed programme for the subjects.

2.3 Human health There are no proposed programmes for subjects that could affect human health. As a result, the proposed Plan will have no effect on human health.

2.4 The enjoyment of the natural environment Numerous proposed programmes detail the effects that the subjects of the Proposal may have on the enjoyment of the natural environment. For many subjects, they can affect the enjoyment of the natural environment through the same mechanisms by which they affect the ecosystems themselves. That is, their invasive characteristics and an ability to dominate the environment. This can directly affect activities that people enjoy - for example, invasive aquatic plants clogging waterways where people wish to swim - or alter ecosystems in a way that reduces their aesthetic value - for example, forest areas dominated with in invasive climber.

The effective management of those subjects or preventing their establishment in Marlborough will have significant positive benefits to the way in which the people of Marlborough enjoy the natural environment.

Further detail on specific subjects can be found under the each proposed programme for the subjects.

2.5 The relationship with Māori and their culture and their traditions and their ancestral lands, waters, sites, wāhi tapu and taonga

The Plan’s implementation is anticipated to have some significant positive effects on Māori culture and traditions. Specifically, this will be through reducing the incidence of those subjects that are established and could degrade ancestral lands, waters, sites, wāhi tapu and taonga if left unmanaged. Similarly, preventing the establishment of new invasive species in Marlborough will have significant positive effects for the same reason.

2.6 The marketing overseas of New Zealand products In the opinion of Council, the proposed programmes within the Proposal will have no material effect on the marketing of New Zealand products overseas.


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3. Relationship with other pest management or pathway plans

This Proposal for a Plan will not affect any other pest management plan or pathway management plan currently in place.

4. Responsibilities and obligations 4.1 The management agency Council is the management agency responsible for implementing the proposed Plan. Council is satisfied that it meets the requirements of section 100 of the Act in that it:

a) is accountable to the Plan funders, including any Crown agencies, through the requirements of the Local Government Act 2002;

b) is acceptable to the funders and those persons subject to the proposed Plan management provisions because it implemented previous Regional Pest Management Strategies; and

c) has the capacity, competency and expertise to implement the proposed Plan.

4.2 Compensation and disposal of receipts The proposed Plan does not provide for compensation to be paid to any persons meeting their obligations under its implementation. However, should the disposal of a pest or associated organism provide any net proceeds, a person will be paid disbursement in the manner noted under section 100I of the Act.

4.3 Affected parties 4.3.1 Occupiers For some proposed programmes, occupiers are responsible for the management of pests in accordance with the applicable rules for that programme. They may also be obliged to report new incidences of the pest not previously known about.

While not normally required, if occupiers are found to be not complying with their obligations, Council can use enforcement and/or prosecution provisions available within the Act (see section 10).

The term occupier has a wide definition under the Act and includes:

• the person who physically occupies the place; and

• the owner of the place; and

• any agent, employee or other person acting or apparently acting in the general management or control of the place.

Under the Act, place includes: any building, conveyance, craft, land or structure and the bed and waters of the sea and any canal, lake, pond, river or stream.

An owner and/or occupier cannot stop an authorised person from entering a place at any reasonable time to

• find out whether pests are on the property;

• manage pests; or

• ensure the owner and/or occupier is complying with biosecurity law.

While the occupier may choose the methods they will use to control any pests, they must also comply with the requirements under other legislation (e.g. Resource Management Act and/or the Hazardous Substances and New Organisms Act 1996).

http://www.legislation.govt.nz/act/public/1996/0030/latest/DLM381222.html



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This Proposal treats all private land equitably and emphasises the responsibilities and obligations of all occupiers, including Māori. Council acknowledges the complex and variable relationships of Māori land ownership and occupation. This includes multiple owners (including lessees) or a range of corporate management systems under the Companies Act 1993 or Te Ture Māori Whenua Act 1993. Where owners and/or occupiers are unknown, the Māori Land Court or the Registrar of Companies may help to identify and communicate with them.

4.3.2 Road reserves The Act allows the option of making either road authorities or adjoining occupiers responsible for pest management in road reserves (see section 6(1) of the Act).

As such, it is proposed that Marlborough Roads (a company responsible for managing both state highways and local authority roads in Marlborough) is required to control the subjects of this Proposal in accordance with Plan objectives and rules, within all formed road reserves, including: a) rest areas; b) weighpit and stockpile sites; c) except where:

i) the boundary is unfenced and the adjacent owner has ready access to the road reserve; ii) the proposed pests broom (Cytisus scoparius) and gorse (Ulex europaeus) have

encroached from adjacent land onto road reserve and are endemic to the locality; iii) access is not directly available from legal road but from adjacent land; in which case the

adjacent occupier will be deemed to be responsible.

Adjoining occupiers are required to control pests on all unformed roads (“paper roads”).

5. Relationship with the National Policy Direction (NPD) The NPD was approved by the Governor-General on 24 September 2015. The stated purpose of the NPD is to ensure that activities under Part 5 of the Act (Pest Management) provide the best use of available resources for New Zealand’s best interests, and align with each other (when necessary), to help achieve the purpose of Part 5. Table 1 sets out the NPD requirements and the steps taken to comply with them.

Table 1: Steps taken by Council to meet NPD requirements

NPD requirements Steps taken to comply Programme is described Checked that the types of programmes

(described in Part 2 of the Proposal) comply with Clause 5 of the NPD.

Objectives are set Checked that the objectives uses for programmes in Part 2 of the Proposal comply with Clause 6 of the NPD.

Benefits and costs are analysed Undertook an assessment of the level of analysis required for each proposed subject in accordance with Clause 6(1). Carried out the appropriate analysis for each subject in accordance with Clause 6(2).

Funding rationale is noted Checked the funding rationale described in section 11 of the Proposal has been developed in line with Clause 7 of the NPD.

Good Neighbour Rules (GNRs) are described GNRs have been developed in line with Clause 8 of the NPD. Further detail can be found in the relevant section of the supporting information document to this Proposal.


https://www.google.co.nz/search?q=Te+Ture+Whenua+Act&hl=en-NZ&biw=&bih=&gbv=2&oq=Te+Ture+Whenua+Act&gs_l=heirloom-serp.3..0l2j0i22i30.12416.12416.0.12666.1.1.0.0.0.0.234.234.2-1.1.0....0...1ac.1.34.heirloom-serp..0.1.234.TREjIL59xD0


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Part Two Proposed Programmes

6. The subjects of this Proposal The plants, animals and organisms listed in Table 2 are proposed to be managed through programmes within the Plan for Marlborough. As a result, these organisms would be declared pests in accordance with the Act. The table also indicates what management programme or programmes will apply to the pest and if a Good Neighbour Rule (GNR) applies.

Attention is also drawn to:

• The general administrative powers of inspection and entry, contained in Part 6 of the Act, which would be made available to the Council; and

• The statutory obligations of any person under sections 52 and 53 of the Act. These sections prohibit anyone from selling, propagating or distributing any pest, or part of a pest, should they be specified as such in a Plan. Not complying with sections 52 and 53 is an offence under the Act and may result in the penalties noted in section 157(1) of the Act.

Table 2: Subjects proposed to be managed within the Plan for Marlborough

Common Name Scientific Name Management Programme

GNR Applies?

African feather grass Cenchrus macrourus Sustained Control

Bathurst bur Xanthium spinosum Sustained Control

Boneseed Chrysanthemoides monilifera Sustained Control

Broom Cytisus scoparius Sustained Control Yes

Brushtail possum Trichosurus vulpecula Exclusion

Bur daisy Calotis lappulacea Eradication

Cathedral bells Cobaea scandens Sustained Control

Chilean needle grass Nassella neesiana Sustained Control

Chinese pennisetum Pennisetum alpecuroides Sustained Control

Climbing spindleberry Celastrus orbiculatus Eradication

Contorta pine Pinus contorta Sustained Control

Corsican pine Pinus nigra Sustained Control

Cotton thistle Onopordum acanthium Sustained Control

Eel grass Vallisneria australis Sustained Control

European larch (excluding sterile hybrids)

Larix decidua Sustained Control

Evergreen buckthorn Rhamnus alaternus Sustained Control

Giant needle grass Austristipa rudis Sustained Control

Gorse Ulex europaeus Sustained Control Yes

Kangaroo grass Themeda triandra Sustained Control

Madeira vine Anredera cordifolia Sustained Control

Mediterranean fanworm Sabella spallanzanii Exclusion

Moth plant Araujia hortorum Sustained Control

Mountain pine (Including Pinus mugo Sustained Control


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Common Name Scientific Name Management Programme

GNR Applies?

all sub-species and botanical variants)

Nassella tussock Nassella trichotoma Sustained Control

Parrots feather Myriophyllum aquaticum Sustained Control

Purple loosestrife Lythrum salicaria Sustained Control

Rabbits Oryctolagus cuniculus Sustained Control

Reed sweet grass Glyceria maxima Sustained Control

Rooks Corvus frugilegus Exclusion

Rough horsetail Equisetum hyemale Sustained Control

Saffron thistle Carthamus lanatus Sustained Control

Scots pine Pinus sylvestris Sustained Control

Senegal tea Gymnocoronis spilanthoides Exclusion

Spartina Spartina anglica Eradication

Tall wheat grass Thinopyrum ponticum Sustained Control

Wallabies Family Macropodidae Exclusion

Western white pine Pinus monticola Sustained Control

White-edged nightshade Solanum marginatum Sustained Control

Wilding conifers Various sp. Sustained Control

Willow-leaved hakea Hakea salicifolia Eradication

Woolly nightshade Solanum mauritianum Sustained Control

6.1 Pest management programmes - What you’ll find in this Proposal For each subject, a consistent structure has been used to both clearly articulate the steps taken in assessing the subject and to meet the process requirements within the Act and NPD. For each each subject you will see some introductory background following by the following headings :

Objective

Each objective has been developed to be both specific, measureable, achievable, realistic, time-bound and also in accordance with the five options available within the NPD:

1. “Exclusion Programme” (if applicable) in which the intermediate outcome for the programme is to prevent the establishment of the subject, or an organism being spread by the subject, that is present in New Zealand but not yet established in an area.

2. “Eradication Programme” (if applicable) in which the intermediate outcome for the programme is to reduce the infestation level of the subject, or an organism being spread by the subject, to zero levels in an area in the short to medium term.

3. “Progressive Containment Programme” (if applicable) in which the intermediate outcome for the programme is to contain or reduce the geographic distribution of the subject, or an organism being spread by the subject, to an area over time.

4. “Sustained Control Programme” (if applicable) in which the intermediate outcome for the programme is to provide for ongoing control of the subject, or an organism being spread by the subject, to reduce its impacts on values and spread to other properties.


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5. “Site-led Pest Programme” (if applicable) in which the intermediate outcome for the programme is that the subject, or an organism being spread by the subject, that is capable of causing damage to a place is excluded or eradicated from that place, or is contained, reduced or controlled within the place to an extent that protects the values of that place.

Principal measures to achieve programme objectives

This section outlines the various measures that Council (or others) propose to carry out in order to implement the proposed programme.

They are usually in a hierarchy with those used by preference listed first.

Rules

If Rules are proposed to be used to support the programme implementation, they will appear as they would in a final Plan followed by an explanation of the purpose of the Rule in accordance with section 73(5) of the Act.

Analysis of benefits and costs

Using the outcome of the assessment within the supporting document to this Proposal, the analysis is structured in a similar manner for all subjects. For subjects assessed as requiring a medium level of assessment, it includes the use of economic modelling to provide a Net Present Value of intervening, plus a sensitivity analysis.

Key sub-headings include:

• Impacts – an outline of the nature of impacts the subject can cause and quantifiable if possible.

• Beneficiaries and exacerbators – a summary of major and minor beneficiaries (those who benefit from intervening) and exacerbators (those who exacerbate the issue). Because there are consistencies across all subjects, a grouping exercise has been undertaken. The grouping where the subject has been assessed as being within is highlighted –see example below.

The single exception is the proposed programme for Mediterranean fanworm. This programme does not occur on rateable land. As such, a more detailed cost allocation breakdown has been developed that covers the wider programme cost and is outlined specifically within the proposed programme section.

EXAMPLE – the subject is within Grouping 3 with respect to beneficiaries and exacerbators.

Beneficiaries Exacerbators

Grouping Major Minor Major Minor

1 Regional community Occupiers of susceptible land

2 Occupiers of susceptible land

Occupiers with the pest present


Regional community


4 Regional community Occupiers with the pest present

• Benefits – the benefits from intervening AND/OR benefits provided by the subject.

• Costs – the costs of intervening AND/OR the costs on the effects on values.


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• Cost allocation and rationale - commonly referred to section 11.3 and 11.4 where the cost allocation and rationale has been centralised.

• Assumptions – lists any assumptions used in the analysis.

• Risk – outlines a summary of risks that were generated from the documented within the supporting information to the Proposal.

• Mitigation – details any risk mitigation measures that were assessed (if any).

• Preferred option – identifies the most preferred option as an outcome of the analysis that relates back to the programme objective within the Proposal.

7. Programmes 7.1 African feather grass (Cenchrus macrourus) Why is it a threat? African feather grass is a robust, perennial grass with spreading rhizomes that originates from tropical and southern Africa. It forms dense tussocks and produces long, narrow flower heads. It is a garden plant that has escaped into surrounding habitat. It spreads utilising seeds and rhizomes. African feather grass is unpalatable to stock and is a threat to pastoral production if left uncontrolled. This plant is very adaptable and will also displace native species in wetlands. It will colonise pastoral land, wetlands, roadsides, urban areas and forest margins throughout Marlborough if it went uncontrolled.

Reasons for proposing a plan African feather grass has in the past been classified as a noxious plant. It has been actively managed by Council since 1996. The investment in controlling African feather grass over the last 20 years has resulted in the reduction of sites from 12 to 7. The number of plants controlled each year continues to decline.

There is a significant net benefit to the control of African feather grass based on the potential for damage to Marlborough’s pastoral farming economy and the potential to displace Marlborough’s native species.

Why the Plan is more appropriate than relying on voluntary actions With so few known sites, the management of this species needs to be both strategic and intensive. Because of this, it is more appropriate to be managed with a structured programme of delivery enabled by a Plan rather than relying on voluntary actions.

7.1.1 Objective Over the duration of the Plan, control of African feather grass (Cenchrus macrourus) in the Marlborough district to less than or equal to 2016 levels to minimise adverse effects on economic wellbeing, the environment and enjoyment of the natural environment.

Intermediate Outcome:

Exclusion Eradication Progressive Containment

Sustained Control Site-led

Principle measures to achieve the objective 1) Council Inspection and Service Delivery

a) Inspection by Council may include staff or contractors.


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b) Delivering a service to manage African feather grass in liaison with the occupier.

c) Visiting properties or doing surveys to determine whether pests are present.

d) Monitoring effectiveness of control.

e) Carry out control using administrative powers of the Biosecurity Act 1993, if necessary.

2) Requirement to Act

a) Land owners and/or occupiers or other persons may be required to act where rules or statutory obligations dictate.

b) The presence of pests is to be reported.

c) Pests are not to be spread (propagated, sold or distributed).

3) Advocacy and Education

Council may:

a) Provide general purpose education, advice, awareness and publicity activities to land owners and/or occupiers and the public about pests and pathways (and control of them).

b) Encourage land owners and/or occupiers to control pests.

c) Promote industry requirements and best practice to contractors and land owners and/or occupiers.

d) Encourage land owners and/or occupiers and other persons to report any pests they find.

e) Facilitate or commission research.

7.1.2 Rules Rule 7.1.2.1 Occupiers are required to notify Council of any new infestation of African feather grass (Cenchrus macrourus) on land that they occupy within 5 working days of the initial observation.

A breach of this rule will create an offence under section 154N(19) of the Act.

Note: Current distribution data is able to be viewed online via Council’s Smart Maps service.

Explanation of the rule: The purpose of this rule is for occupiers to assist Council with surveillance. Requiring occupiers to notify Council of new sites and plants on their properties in addition to Council’s own monitoring will assist Council in achieving the objective of the programme. New infestations will be able to be controlled and incorporated into the programme.

Notifying the Council of the presence of the specified pest will enable the Council to:

• Update its records.

• Map new sites of this pest.

• Carry out control work before they spread.

• Determine whether new control regimes should be considered.

• Provide advice and information to occupiers where appropriate.

Council as the management agency will administer the rule.


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7.1.3 Analysis of the benefits, costs and cost allocation for African feather grass

Level of analysis for African feather grass Council has determined that a low level of analysis be undertaken for African feather grass. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.

BackgroundAfrican feather grass became a total control pest plant in the Regional Pest Management Strategy for Marlborough in 1996. Prior to 1996 it was managed under the Noxious Plants Act. There were three sites of African feather grass infestation at Wharanui, Riverlands and Ngakuta Bay, Grove Arm. The infestations at Wharanui and Riverlands were so extensive prior to 1996 that they were sprayed by helicopter.

Council has controlled African feather grass infestations annually since 1996. In 2001 an impact and economic analysis was undertaken to justify its continued inclusion in the Regional Pest Management Strategy for Marlborough 2001.

In 2006/2007 a new site was discovered in the Grovetown Lagoon area while carrying out surveillance work. In 2007/2008 there was a significant increase in the number of plants controlled at Ngakuta Bay, Grove Arm. Usually the site was mowed and this had been keeping the infestation under control. In 2007 the site was not mowed and as a result African father grass seedlings emerged. The high numbers of plants controlled in subsequent years were at this site.

African feather grass continued to be included in the Regional Pest Management Strategy for Marlborough 2007 and is declared a Total Control pest plant in the current Regional Pest Management Strategy for Marlborough 2012.

Current situation in 2017Currently there are four areas in Marlborough with African feather grass infestations. These are Wharanui, Riverlands, Grovetown Lagoon and the Grove Arm.

African feather grass is very limited in distribution and the number of plants controlled is declining. Each year, Council visits the 7 sites where plants continue to be found and undertake control and search surrounding areas. There are 19 sites where plants have not been found for a very long time.

African feather grass has been recorded as infesting 82 hectares in Marlborough.

Figure 2: The trend in infestation levels of African feather grass in Marlborough


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Options to respond to African feather grass Baseline: No RPMP (do nothing) In this scenario no control of African feather grass is undertaken and the assumption is made that the plant becomes well-established and progresses toward full naturalisation in all susceptible areas in the long term.

Control option(s): 1. Eradication Programme: In which the intermediate outcome for the programme is to reduce

the infestation level of the subject to zero levels in an area in the short to medium term.

2. Sustained Control: In which the intermediate outcome for the programme is to provide for ongoing control of the subject, to reduce its impacts on values and spread to other properties.

Impacts African feather grass is a robust, perennial grass with spreading rhizomes that originates from tropical and southern Africa. It forms dense tussocks and produces long, narrow flower heads. It is a garden plant that has escaped into surrounding habitat. It spreads utilising seeds and rhizomes.

Identify impact Quantify impact

Economic Threat to pastoral production if left uncontrolled. Unpalatable to stock. Diminished pasture and livestock production.

It is estimated that African feather grass will infest pastoral and tussock land covers, including 10% of LUC1 Class III land, 50% of Hill country land (Classes IV and V), and 30% of Class VI land.

Conservation values It will colonise pastoral land, wetlands, roadsides, urban areas and forest margins throughout Marlborough if it went uncontrolled. This plant is very adaptable and will displace native species in wetlands.

Control of African feather grass will prevent damage to 250,000 hectares of pastoral and tussock habitat.

Regional Values The values protected by the control of African feather grass are in large part (>99%) regional values because the infestations are limited and the majority of damage will occur to parties other than those on whose properties African feather grass is currently located.

The extent to which any persons are likely to benefit from the Plan and the extent to which any persons contribute to the creation, continuance or exacerbation of the problem Beneficiaries Exacerbators






Regional community


1 Land Use Capability Index


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Benefits of each option

Benefit Option

No RPMP Eradication Sustained Control

The prevention of African feather grass infesting new areas and the resulting impact of that on pastoral production values.

No programme cost The values protected by the control of African feather grass are largely pastoral production values. Control of African feather grass will prevent damage to 250,000 hectares of pastoral and tussock habitat. The benefit under an Eradication Programme will increase to an end point when the objective is able to be achieved.

The values protected by the control of African feather grass are largely pastoral production values. Control of African feather grass will prevent damage to 250,000 hectares of pastoral and tussock habitat. The benefit under a Sustained Control Programme will remain constant throughout the life of the Plan, with no end point.

The prevention of African feather grass infesting new areas and the resulting impact of that on environmental values.

No programme cost There are ecosystems throughout Marlborough that would be vulnerable to invasion from African feather grass. Preventing African feather grass expanding its range and infestation levels will provide benefit to natural ecosystems from another invasive species. The benefit under an Eradication Programme will increase to an end point when the objective is able to be achieved.

There are ecosystems throughout Marlborough that would be vulnerable to invasion from African feather grass. Preventing African feather grass expanding its range and infestation levels will provide benefit to natural ecosystems from another invasive species. The benefit under a Sustained Control Programme will remain constant throughout the life of the Plan, with no end point.

Costs of each option

Programme Costs

Option

No RPMP Annual cost (excl

GST)

Eradication Annual cost (excl

GST)

Sustained Control Annual cost (excl

GST)

Council costs • Control • Surveillance • Administration • Education/awareness

- $50,000+ $10,239

Land occupier costs - - -

Total - $50,000+ $10,239


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Costs of effects on values Low, but increases exponentially

over time

Insignificant Insignificant

Proposed allocation of costs The proposed programme costs are to be 100% Council costs, allocated across the various rating districts used in Marlborough under the Local Government (Rating) Act 2002. For further detail, see sections 11.3 and 11.4.

Rationale for the allocation of costs For this detail, see sections 11.3 and 11.4.

Assumptions on which the impacts, benefits and costs are based That under a no RPMP scenario, voluntary control will not cause any reduction in the future spread and/or impact over time.

Risk that each option will not achieve the objective The supporting information document to this Proposal contains further information to support this analysis. A summary is outlined below:

Level of Risk

Option


N/A High Low

Reason The level of risk of not achieving an eradication objective within 10 years or an even longer time scale is very high. African feather grass has been intensively managed for over 20 years. This has shown the difficult nature in completely eradicating an established pest plant species.

There is a lower level of risk that Council will be able to maintain a very low density of African feather grass in Marlborough. This will be achieved by ongoing control at sites and with structured surveillance of all known sites and other risk areas over time.

Mitigation options No mitigation options are assessed as being available to adjust the level of risk of options not achieving the objective.

Most preferred option Sustained Control Programme


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7.2 Bathurst bur (Xanthium spinosum) Why is it a threat? Bathurst bur is a shrubby annual that originates from South America. It spreads utilising hooked seeds. These hooked seeds, along with their long sharp spines, injure stock and contaminate wool. Bathurst bur will also displace preferred pasture species. It will interfere with cereal harvesting if left uncontrolled.

Reasons for proposing a plan Bathurst bur has in the past been classified as a noxious plant, then subsequently as a pest plant under early Regional Pest Management Strategies. It has been actively managed by Council and former authorities. The investment in controlling bathurst bur over the last 20+ years has resulted in the reduction of sites from 32 to two. The number of plants controlled each year has diminished over that time until some soil disturbance in one of the affected areas resulted in some re-emergence. This demonstrates the importance of vigilance associated with a structured programme within a Plan.

There is a significant net benefit to the control of bathurst bur based on the potential for damage to Marlborough’s pastoral and arable farming economy.

Why the Plan is more appropriate than relying on voluntary actions If control was left to the voluntary actions of occupiers and no control was undertaken, then the plant would spread throughout the region causing impacts to the pastoral and arable industries. The locations and levels of bathurst bur have reduced over the last 20+ years through its inclusion in Regional Pest Management Strategies. The inclusion of bathurst bur in the Plan will ensure this pest plant is kept under control and managed to zero density.

7.2.1 Objective Over the duration of the Plan, control bathurst bur (Xanthium spinosum) in the Marlborough district to less than or equal to 2014 levels to minimise adverse effects on economic wellbeing, the environment and enjoyment of the natural environment.





Inspection by Council may include staff or contractors:

a) Delivering a service to control bathurst bur in liaison with the occupier.

b) Visiting properties or doing surveys to determine whether pests are present.

c) Monitoring effectiveness of control.

d) Carry out control using administrative powers of the Biosecurity Act 1993, if necessary.


Land owners and/or occupiers or other persons may be required to act where rules or statutory obligations dictate:

a) The presence of pests is to be reported.

b) Pests are not to be spread (propagated, sold or distributed).


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Council may:




d) Encourage land owners and/or OCCUPIERS and other persons to report any pests they find.


7.2.2 Rules Rule 7.2.2.1 Occupiers are required to notify Council of any new infestation of bathurst bur (Xanthium spinosum) on land that they occupy within 5 working days of the initial observation.

A breach of this rule will create an offence under section 154N(19) of the Biosecurity Act.


Explanation of the rule: The purpose of this rule is for occupiers to assist Council with surveillance. Requiring occupiers to notify Council of new sites and plants on their properties in addition to Council’s own surveillance will assist Council in achieving the objective of the programme. New infestations will be able to be controlled and incorporated into the programme.








7.2.3 Analysis of the benefits and costs for bathurst bur Background Bathurst bur became a Total Control pest plant in the Regional Pest Management Strategy for Marlborough in 1996. Prior to 1996 it was managed under the Noxious Plants Act. In 1996 there were two areas in Marlborough with bathurst bur infestations; at Riverlands and David Street, Blenheim. Infestations were scattered over several properties in these areas.

Council has controlled bathurst bur infestations annually since 1996. In 2001 an impact and economic analysis was undertaken to justify its continued inclusion in the Regional Pest Management Strategy for Marlborough 2001.

A new area was found at Grovetown in 2007/2008. The area has been controlled and no plants have been found at this site for a number of years.

Bathurst bur continued to be included in the Regional Pest Management Strategy for Marlborough 2007 and is declared a Total Control pest plant in the current Regional Pest Management Strategy for Marlborough 2012.


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No plants have been found at the historical sites for a number of years until early 2014, when two new sites were discovered in the David Street area close to historical sites as a result of a single soil disturbance activity.

Current situation in 2017Bathurst bur infestations have occurred at Grovetown, David Street and Riverlands.

The infestation levels at two of the three geographical areas have reached zero levels. At David Street a new infestation on two sites has recently been discovered adjacent to historical areas. This new infestation will fall into an annual control regime while all others will continue under a monitoringregime to confirm that no new bathurst bur emerge over the life of the Plan.

Council staff grub or spray seedlings that emerge annually from January to April. All plants are bagged, removed and destroyed.

Figure 3: The trend in infestation levels of bathurst bur in Marlborough.

Options to respond to bathurst burBaseline: No RPMP (do nothing)In this scenario no control of bathurst bur is undertaken and the assumption is made that the plant becomes well-established and progresses toward full naturalisation in all susceptible areas in the long term.

Control option(s):1. Eradication Programme: In which the intermediate outcome for the programme is to reduce


2. Sustained Control Programme: In which the intermediate outcome for the programme is to provide for ongoing control of the subject, to reduce its impacts on values and spread to other properties.

Level of analysis for bathurst burCouncil has determined that a low level of analysis be undertaken for bathurst bur. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.


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Impacts Bathurst bur is a shrubby annual that originates from South America. It spreads utilising hooked seeds. These hooked seeds, along with their long sharp spines, injure stock and contaminate wool. Bathurst bur will also displace preferred pasture species. It will interfere with cereal harvesting if left uncontrolled.


Economic Pastoral production values. Diminished pasture and livestock production.

Control of bathurst bur will prevent damage to 80,000 hectares of pastoral habitat. It is estimated that bathurst bur will infest pastoral and tussock land covers, including 5% of more intensive pastoral land uses (LUC2 Classes I, II and III ) and 10% of pastoral hill country land (Classes IV and V). Modelling of this scenario assumed spread characteristics of between 5 and 50 metres for mature plants, and between 15 and 40 years to reach its maximum density at a site in an uncontrolled situation.

The extent to which any persons are likely to benefit from the Plan and the extent to which any persons contribute to the creation, continuance or exacerbation of the problem







Regional community





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Benefit Option


The prevention of bathurst bur infesting new areas and the resulting impact of that on pastoral production values.

No programme cost

The values protected by the control of bathurst bur are largely pastoral production values. The eradication of bathurst bur will prevent damage to 80,000 hectares of pastoral and tussock habitat. The benefit under an Eradication Programme will increase to an end point when the objective is able to be achieved.

The values protected by the control of bathurst bur are largely pastoral production values. The eradication of bathurst bur will prevent damage to 80,000 hectares of pastoral and tussock habitat. The benefit under a Sustained Control Programme will remain constant throughout the life of the Plan, with no end point.


Programme Costs

Option


GST)


GST)


GST)


- $20,000+ $3,073

Land occupier costs - -

Total - $20,000+ $3,073

Costs of effects on values

Low, but increases exponentially

over time




Assumptions on which the impacts, benefits and costs are based That under a No RPMP scenario, voluntary control will not cause any reduction in the future spread and/or impact over time.


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Risk that each option will not achieve the objective The supporting information document to this Proposal contains further information to support this analysis. A summary is outlined below.

Level of Risk

Option


N/A High Low

Reason Bathurst bur is very limited in distribution. Council will continue to visit the two sites where plants continue to be found and undertake control and search surrounding areas. The 30 sites where plants have not been found for a very long time will continue to be monitored. Given there are so few active sites, they are readily accessible. The level of risk is not high. However, it is evident the seed is very long long-lived and readily germinate as a result of any ground disturbance. Therefore, there is a high level of risk that eradication is not feasible.

Bathurst bur is very limited in distribution. Council will continue to visit the two sites where plants continue to be found and undertake control and search surrounding areas. The 30 sites where plants have not been found for a very long time will continue to be monitored. Given there are so few active sites, they are readily accessible. The level of risk is not high. However, it is evident the seed is long-lived. Therefore, the risk is not low.




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7.3 Boneseed (Chrysanthemoides monilifera) Why is it a threat? Boneseed is an evergreen perennial shrub that originates from the Cape region of South Africa. It has a vigorous root system, produces many seeds, which are resistant to fire, and tolerates very dry conditions. Birds disperse its seed as a result of eating its fruit. The fruit falls to the ground if not eaten. It is one of New Zealand’s most serious environmental weeds, as it will displace native species on coastal cliffs, in salt marshes and on sand dunes. It will grow on islands, sand dunes and coastal cliffs and in disturbed or regenerating forest, ungrazed pasture, riverbeds, roadsides, parks, quarries, wastelands and exotic plantations.

Reasons for proposing a Plan Boneseed has long been recognised as a highly invasive weed in coastal areas and other similar environments further inland. Infestations exist throughout New Zealand in coastal areas, excluding the South Island west coast and coastal Southland. It is especially prevalent on Banks Peninsula in Canterbury.

Infestations in Marlborough are limited to areas in Tory Channel, Karaka Point, Ruakaka Bay, Snake Point, Ocean Bay, Glasgow Island, Rarangi and a small infestation near Timara Lodge. By proposing a programme within a Plan, the gains made over previous years in initially knocking down populations then sustaining them at low levels, can continue into the future.

Why the Plan is more appropriate than relying on voluntary actions The infestations known in the Marlborough Sounds exist primarily across steep, difficult terrain with access from boat the only option. These areas are not actively ‘tended to’ by occupiers. Relying on voluntary actions would result in little to no management of this invasive species and lead to the uninhibited spread of boneseed through coastal scrub and dune habitats.

7.3.1 Objective Over the duration of the Plan, control boneseed (Chrysanthemoides monilifera) in the Marlborough district to less than or equal to 2015 levels to minimise adverse effects on the environment and enjoyment of the natural environment.






a) Delivering a service in conjunction with the Department of Conservation to manage boneseed.





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a) Land owners and/or occupiers or other persons may be required to act where rules or statutory obligations dictate.


c) Pests are not to be spread (propagated, sold or distributed).


Council may:






7.3.2 Rules Rule 7.3.2.1 Occupiers are required to notify Council of any new infestation of boneseed (Chrysanthemoides monilifera) on land that they occupy within 5 working days of the initial observation.

A breach of this rule will create an offence under section 154N(19) of the Biosecurity Act 1993.










7.3.3 Analysis of the benefits and costs for boneseed Background There were numerous infestations in the Queen Charlotte Sound/Tory Channel area of the Marlborough Sounds and isolated infestations at Rarangi and Lake Timara.

An impact and economic analysis was undertaken in 2001. As a result boneseed was included in the Regional Pest Management Strategy 2001 as a Total Control pest plant.


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The majority of sites have seen a large reduction in plant densities since management began under a joint initiative with the Department of Conservation in 2001. Many isolated infestations in the Marlborough Sounds are now historical and under a surveillance regime. All others are under an ongoing annual control regime.

Boneseed continued to be included in the Regional Pest Management Strategy for Marlborough 2007and is declared a Total Control pest plant in the current Regional Pest Management Strategy for Marlborough 2012.

Current situation in 2017All sites that are not historical are visited every year by Council and/or Department of Conservationstaff with all plants found destroyed. Historical sites are visited on a less frequent basis to ensure any re-emergence does not occur.

With some sites, the terrain and land cover has become too treacherous to undertake the control work on the ground. As a result, other methodologies, such as aerial spot spraying, have been deployed with great success. However, this technique is restricted to the control of larger, more visible plants.

Figure 4: The trend in infestation levels of boneseed in Marlborough

Options to respond to boneseed Baseline: No RPMP (do nothing)In this scenario no control of boneseed is undertaken and the assumption is made that the plant becomes well-established and progresses toward full naturalisation in all susceptible areas in the long term.





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Level of analysis for boneseed Council determined that a low level of analysis be undertaken for boneseed. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.

Impacts Boneseed is an evergreen perennial shrub that originates from the Cape region of South Africa. It has a vigorous root system, produces many seeds, which are resistant to fire, and tolerates very dry conditions. Birds disperse its seed as a result of eating its fruit. The fruit falls to the ground if not eaten.


Conservation values It is one of New Zealand’s most serious environmental weeds, as it will displace native species on coastal cliffs, in salt marshes and on sand dunes. It will grow on islands, sand dunes and coastal cliffs and in disturbed or regenerating forest, ungrazed pasture, riverbeds, roadsides, parks, quarries, wastelands and exotic plantations. Displaces native species in coastal areas.

At threat is 50% of 32,000 hectares of coastal scrub and dune habitats.







Regional community




Benefit Option


The prevention of boneseed infesting new areas and the resulting impact of that on environmental values.

No programme cost The benefit under an Eradication Programme will increase to an end point when the objective is able to be achieved.

The benefit under a Sustained Control Programme will remain constant throughout the life of the Plan, with no end point.


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Programme Costs

Option


GST)


GST)


GST)

Operational costs • Control • Surveillance • Administration • Education/awareness

- MDC $120,000+ DOC $30,000+

MDC $41,000 DOC $10,000


Total - $150,000+ $51,000


over time


Proposed allocation of costs As outlined, costs have been allocated across both the regional community (Council) and the Department of Conservation.

The proposed programme costs for Council are to be allocated across the various rating districts used in Marlborough under the Local Government (Rating) Act 2002. For further detail, see sections 11.3 and 11.4.

Rationale for the allocation of costs It has been recognised that due to the location of the infestations of boneseed in Marlborough, being often located within the thin ribbon of Department of Conservation Foreshore Reserve in the Marlborough Sounds, the Department of Conservation wishes to co-manage this species. As such, a portion of the cost of the programme has been allocated to the Department of Conservation. This is in recognition of the Department of Conservation being both a beneficiary and exacerbator (passive) for this species



Level of Risk

Option


N/A High Low

Reason The level of risk of not achieving an eradication objective, within 10 years or even longer, is high risk.

There is a lower level of risk that Council in association with the Department of Conservation will be able to maintain a very low density of boneseed in Marlborough.


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7.4 Broom (Cytisus scoparius) Why is it a threat? Broom is an erect perennial shrub that will grow up to 3 metres high and originates from Eurasia. It will form dense patches if left uncontrolled. It seeds explosive fruits, which are resistant to fire. Broom will displace preferred pasture species and dense patches impede stock access. It will grow on pastoral country, in hedgerows, waste places and plantations from the coast to high altitudes. Its vigorous growth habit will displace native herbaceous species. The presence of broom will greatly reduce the economic viability of a farming unit.

Reasons for proposing a Plan Broom has in the past been classified as a noxious plant then subsequently as a pest under early Regional Pest Management Strategies. In Marlborough, there has been a concerted control programme initiated by the community in the Upper Awatere Valley for a number of years. There has also been an ongoing programme within the Upper Wairau Valley to prevent broom becoming established in the upper reaches of this catchment.

There is a significant net benefit to the control of broom based on the potential for damage to Marlborough’s pastoral farming economy.

Why the Plan is more appropriate than relying on voluntary actions If control was left to the voluntary actions of occupiers and no control was undertaken, there is a real risk that adequate management would not occur. The inclusion of a programme for broom in the Plan will ensure this pest plant is kept under control with the values of the catchments identified protected.

7.4.1 Objectives 7.4.1.1 Over the duration of the Plan, control broom (Cytisus scoparius) in the Upper Awatere

Broom Control Zone (excluding the Middlehurst Gorge Containment Area), Upper Wairau and Waima/Ure Broom and Gorse Control Zones to minimise adverse effects on economic wellbeing, the environment and enjoyment of the natural environment.

7.4.1.2 Over the duration of the Plan, control broom (Cytisus scoparius) across the remainder of the district, in situations where the presence of broom on boundaries threatens adjoining land clear of or being managed for broom, to minimise adverse effects on economic wellbeing, the environment and enjoyment of the natural environment.

Intermediate Outcomes:



Principle measures to achieve the objective 1) Requirement to Act


a) Pests are to be destroyed.


c) Pests are not to be spread (high risk activities, propagated, sold or distributed).


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2) Council Inspection


a) Carrying out inspections to ensure occupiers are meeting obligations.





Council may:






7.4.2 Rules Rule 7.4.2.1 Occupiers within the Upper Awatere Broom Control Zone shall destroy all broom (Cytisus scoparius) plants, on land that they occupy, each year before they produce seed, unless:

a) the land they occupy falls within the Middlehurst Gorge Containment Area (see Map 1), or;

b) a management plan approved by Council is in place.


Rule 7.4.2.2 Occupiers of land within the Middlehurst Gorge Containment Area (see Map 1) shall destroy all broom (Cytisus scoparius), on land they occupy, each year before they produce seed 10 metres inside the Containment Area boundary.


Rule 7.4.2.3 Occupiers within the Upper Wairau Broom and Gorse Control Zone shall destroy all broom (Cytisus scoparius) plants, on land that they occupy, each year before they produce seed, unless:

a) the land they occupy falls within the Upper Wairau Broom and Gorse Containment Area (see Map 2), or;

b) a management plan approved by Council is in place.


Rule 7.4.2.4 Occupiers of land within the Upper Wairau Broom and Gorse Containment Area (see Map 2) shall destroy all broom (Cytisus scoparius), on land they occupy, each year before they produce seed 10 metres inside the Containment Area boundary.



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Rule 7.4.2.5 Occupiers within the Waima/Ure Broom and Gorse Control Zone (see Map 3), shall destroy all broom (Cytisus scoparius) plants, on land that they occupy, each year before they produce seed, unless a management plan approved by Council is in place.


Rule 7.4.2.6 No person shall transport any risk goods into the Upper Awatere, Upper Wairau or Waima/Ure Broom Control Zones that may contain broom (Cytisus scoparius) plant material.


Rule 7.4.2.7 (Good Neighbour Rule) Occupiers shall destroy all broom (Cytisus scoparius) plants, on land they occupy, within 10 metres of their property boundary each year before they produce seed, where:

a) the broom occurs over a stretch of boundary greater than 50 metres in length, and;

b) the adjoining land is clear of, or under management for broom and the land is being used for agricultural production purposes.


Rule 7.4.2.8 Occupiers are required to notify Council of any new infestation of broom (Cytisus scoparius) on land that they occupy within the Upper Awatere, Upper Wairau or Waima/Ure Broom Control Zones within 5 working days of the initial observation.


Note: Current distribution data held by Council is able to be viewed online via Council’s Smart Maps service.

Explanation of the rules: The purpose of Rules 7.4.2.1 - 7.4.2.5 are in accordance with section 73(5)(h) in that all occupiers within the respective Broom Control Zones are being required to take specified actions to prevent the pest establishing on that land.

The purpose of Rule 7.4.2.6 is in accordance with section 73(5)(e) in that activities that may be at risk of introducing broom in to the Control Zones are regulated as the constant re-introduction of broom into the Control Zones via contaminated goods will affect the implementation of the Plan.

The purpose of Rule 7.4.2.7 is in accordance with section 73(5)(h) in that all occupiers of land harbouring an infestation of broom are being required to take specified actions to prevent spread pressure onto adjoining properties where the adjoining land is clear of, or under management for broom and the land is being used for primary production purposes.

The purpose of Rule 7.4.2.8 is for occupiers to assist Council with surveillance. Requiring occupiers to notify Council of sightings, in addition to Council’s own surveillance, will assist Council in achieving the objective of the programme.

Council as the management agency will administer these rules.


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Map 1: Upper Awatere broom programme

32

Map 2: Upper Wairau broom and gorse programme

33

Map 3: Waima/Ure broom and gorse programme

34

7.4.3 Analysis of the benefits and costs for broom Background Broom is widespread over most of Marlborough.

An impact and economic analysis in 2001 for broom recommended that wild broom was classed as a ‘containment control’ plant pest throughout Marlborough and a ‘containment control’ plant pest in the Upper Awatere and Upper Wairau containment areas in the proposed Regional Pest Management Strategy.

Broom was included in the Regional Pest Management Strategy for Marlborough 2001 recognising two areas in Marlborough that were predominantly free of broom. The first was the Upper Wairau Catchment and the second was the Upper Awatere Catchment. In the Upper Wairau Catchment, only isolated infestations of broom existed and generally they were the result of roading and forestry operations. In the Upper Awatere Catchment, one extensive infestation of broom existed but elsewhere the level of infestation of broom was comparatively minor compared with the rest of Marlborough. Because of the low level of infestation, it was thought that it was feasible to attempt to contain broom infestations in these areas, as the benefits outweighed the costs.

The Upper Wairau Catchment was classed as a ‘Broom and Gorse Containment Control Area’. The Upper Awatere Catchment is a ‘Broom Containment Control Area’. Broom was given priority in the Upper Awatere Catchment as it was spreading much faster than gorse. Gorse was confined to the main Awatere river system. Isolated patches of broom existed in a number of the smaller catchments that flow into the upper Awatere River. Those isolated patches had the potential to spread into large areas of high country in the Upper Awatere Catchment.

The same programmes are contained in the Regional Pest Management Strategy for Marlborough 2012.

Current situation in 2017 Broom is currently a Containment Control Pest in the Regional Pest Management Strategy for Marlborough 2012. The existing programme for broom has two components:

1. Two geographical containment areas in the Upper Awatere and Upper Wairau where all broom must be managed by landholders (with some operational exemptions).

2. A boundary-related rule whereby upon complaint, Council can enforce a 10 metre boundary setback when the scenario meets certain criteria.

Broom remains a well-entrenched species across much of the Marlborough district. In the Upper Awatere catchment, while infestations of broom are present, they are scattered, relatively low infestation levels and are under intense management. In the Upper Wairau catchment, the level of broom is by in large zero levels, with the exception of areas at the bottom end of the control area where broom infestations remain. The Waima/Ure catchment is near zero levels with respect to broom infestation.

Options to respond to broom Baseline: No RPMP Control option(s): 1. A combination of three separate programmes.

a) An Eradication Programme proposed for the Upper Awatere and Upper Wairau.

b) A new Exclusion Programme has been proposed for the Waima/Ure catchment. This area has been included as it is believed to have minimal broom infestation. The community has restrictions on the gravel movement into the area and there are extremely high ecological values at threat within the catchment.

c) A Sustained Control Programme for the rest of the district, relating to boundary management.


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Council would continue to investigate other catchments and collaborate with other agencies as required to determine whether regulation within a Plan would be appropriate.

2. A combination of three separate programmes.

a) A Sustained Control Programme proposed for the Upper Awatere and Upper Wairau.

b) A new Exclusion Programme has been proposed for the Waima/Ure catchment. This area has been included as it is believed to have minimal broom infestation. The community has restrictions on the gravel movement into the area and there are extremely high ecological values at threat within the catchment.



3. Sustained Control Programme for the whole district: In which the intermediate outcome for the programme is to provide for ongoing control of the subject, to reduce its impacts on values and spread to other properties. The various aspects of the programme can be defined via the use of multiple objectives, maps and rule wording.

Level of analysis for broom Council has determined that a low level of analysis be undertaken for broom. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.

Impacts Broom is an erect perennial shrub that will grow up to 3 metres high and originates from Eurasia. It will form dense patches if left uncontrolled. It seeds explosive fruits, which are resistant to fire. Broom will displace preferred pasture species and dense patches impede stock access. It will grow on pastoral country, in hedgerows, waste places and plantations from the coast to high altitudes. Its vigorous growth habit will displace native herbaceous species. The presence of broom will greatly reduce the economic viability of a farming unit.


Economic Diminished pasture and livestock production.

There are hundreds of thousands of hectares in Marlborough that are in pastoral production and free from broom infestations. This can either be in landscapes where broom-free and infested land is ‘mixed’ or contiguous broom-free land - as in the case of the proposed zones in this Proposed RPMP. If land becomes infested with broom, costs of control per hectare can range from $100 per hectare for low level infestations up to $1000 per hectare if it takes holds and forms large dense stands. Across all levels of infestation, areas infested reduce the area of land capable of pastoral production3.

3 Syrett, P., Fowler, S.V., Coombs, E.M., Hosking, J.R., Markin, G.P., Paynter, Q.E., Sheppard, A.W., 1999. The potential for biological control of scotch broom (Cytisus scoparius (L.) Link) and related species. Biocontrol News Info. 20, 17N–-34N.


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Biodiversity values South Marlborough in particular, with dry semi-arid landscapes and associated ecosystems, is susceptible to invasion from broom. The impacts of broom can significantly reduce native plant communities in the dry Marlborough landscapes4. It has been well documented in threatening high priority conservation land by out-competing rare and endangered native plants. It has also been shown that when invading braided riverbeds, broom destroys the open habitats required by rare endemic birds and provides cover for their introduced predators5.

Social values In the open landscapes of Marlborough, infestations of broom can also negatively affect visual and scenic values6.








Regional community



4 Department of Conservation 2010. Middlehurst Pastoral Lease Conservation Resources Report. DOCDM-606881. Page 15.

5 Owen S.J 1998. Department of Conservation Strategic Plan for Managing Invasive Weeds. Department of Conservation, Wellington.

6 Department of Conservation 2010. Middlehurst Pastoral Lease Conservation Resources Report. DOCDM-606881. Page 5.


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Benefit Option

No RPMP Combination (1) Combination (2) Sustained Control

The prevention of broom building in density or infesting new areas within the Upper Wairau, Upper Awatere and Waima/Ure Control Zones and the resulting impact of that on pastoral productivity, biodiversity and social values.

No programme cost

The benefit under a combination of programmes, that includes one with an eradication objective, programme will increase over the life of the Plan then plateau.




Programme Costs

Option

No RPMP Annual cost (excl GST)

Combination (1)

Annual cost (excl GST)

Combination (2)


Sustained Control


Council costs • Inspections • Surveillance • Administration • Education/awareness

- $50,000+ $9,000 $9,000

Land occupier costs - $800,000+ $150,000 $150,000

Total - $850,000+ $159,000 $159,000

Costs of effects on values Low, but increases

exponentially over time

Insignificant Insignificant Insignificant

Proposed allocation of costs It is proposed that the majority of the programme costs are allocated to occupiers of land within the control zones outlined within the programme. This has been done by way of rules requiring the occupiers to manage broom.

The portion of the overall programme cost to fall on Council will also be allocated across the various rating districts used in Marlborough under the Local Government (Rating) Act 2002. For further detail, see sections 11.3 and 11.4.

Rationale for the allocation of costs The allocation of costs proposed relates to the beneficiary/exacerbator grouping the broom programme has been assessed as being within. That is, both the major benefactor and exacerbator for this programme are occupiers of Rural land.


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Risk that each option will not achieve the objective The supporting information document to this Proposal contains information to support this analysis.

Level of Risk

Option


N/A High High Low

Reason Due to the established nature of broom in Marlborough, including in the proposed control zone areas, the risk of not eradicating broom within the zones would be very high.

Due to the established nature of broom in Marlborough, the risk of broom becoming established in a particular zone, such as the Waima/Ure, or already established but not yet known of (be it in small amounts) is very high.

Within ongoing and persistent management, as many occupiers already carry out within the control zones, there is a very low risk of not achieving a sustained control objective. In most instances, the level of control will far exceed that required to ensure the populations are not expanding, and this will be encouraged.




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7.5 Brushtail possum (Trichosurus vulpecula) Why are they a threat? The brushtail possum (known as possums) originates from Australia. They were released in New Zealand in the late 1800s to establish a fur trade similar to that flourishing in Australia at the time. Possums selectively browse preferred plant species. They cause extensive canopy defoliation in native forest. They also cause economic damage in exotic forest plantations. Possums will prey on ground and tree nesting birds and their eggs. The possum is a recognised vector in the spread of the disease bovine tuberculosis to domestic livestock. Populations of the possum exist in New Zealand’s North, South and Stewart Islands.

Reasons for proposing a Plan There are 42 islands throughout the Marlborough Sounds area known to have a possum-free status. These islands make up 26,599 hectares of land in total. The majority of these islands are under the management of the Department of Conservation in their entirety and, as a result, associated legislation relating to the release of wildlife provides some protection. However, by land area, only 9,396 hectares, or 35% of the islands, are under the Department of Conservation ownership. It is this remaining 65% of land area under private ownership that forms the reason behind proposing a programme to manage the risk of possums being introduced to these islands.

There is no proposition for there to be a programme to manage possums on ‘mainland Marlborough’. As with many other organisms, possums on the mainland have been addressed within the grouping of established organisms that threaten areas of significance with respect to biodiversity (as outlined within the Draft Biosecurity Strategy for Marlborough).

Why the Plan is more appropriate than relying on voluntary actions The Plan will support efforts to raise the profile of the possum-free (and sometimes pest-free) status of the islands in the Marlborough Sounds. This makes having a Plan in place more appropriate than relying on voluntary actions to help protect the islands.

7.5.1 Objective Over the duration of the Plan, prevent the establishment of brushtail possums (Trichosurus vulpecula) on islands currently known to be possum-free in the Marlborough Sounds (see Appendix 4 and Map 4) to prevent future impacts on the environment and enjoyment of the natural environment.





Inspection by Council, in conjunction with the Department of Conservation, may include staff or contractors:

a) Delivering a service to respond and investigate sightings of possums on the islands.

b) Delivering a service to control possums in liaison with land owners/occupiers if applicable.

c) Carry out surveys to determine whether pests are present.


e) The use of administrative powers of the Biosecurity Act 1993, if necessary.


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Council may:

a) Encourage land owners and/or occupiers and other persons to report any pests they find.

b) Facilitate or commission research.

7.5.2 Rules Rule 7.5.2.1 Any person is required to notify Council of the presence of brushtail possums (Trichosurus vulpecula), observed or suspected on any of the possum-free islands, within 5 working days of the initial observation or suspicion.


Rule 7.5.2.2 No person shall transport, move or distribute brushtail possums (Trichosurus vulpecula) to or within 1 kilometre of a possum-free island listed in Appendix 4 and shown on Map 4.


Explanation of the rule: The purpose of Rule 7.5.2.1 is for the entire community to assist Council with surveillance. Requiring people to notify Council, in addition to the Department of Conservation or Council’s own surveillance, will assist Council in achieving the objective of the programme.

The purpose of Rule 7.5.2.2 is in accordance with section 73(5)(e) is that the transport, movement or distribution of possums within 1 kilometre of the possum-free islands is seen as an activity that can affect measures taken to implement the Plan. There is an increased risk of the assisted introduction of possums over and above the background risk of self-introduction via swimming or arriving on flotsam.


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Map 4: Brushtail possum programme

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7.5.3 Analysis of the benefits and costs for brushtail possum

Background In Marlborough, brushtail possum (possum) populations vary according to habitat types and the effect of control programmes implemented by agencies and individuals. On the offshore islands in the Marlborough Sounds, possums are not known to be established. Collectively these islands cover 26,599 hectares of land that is free from possums.

Both Council and the Department of Conservation wish to see the offshore islands remain possum-free in the future. While the focus for this programme is on possums, it is envisaged that there will be secondary benefits associated with any education and awareness activities. These secondary benefits will relate to other predators or mammals that can also be transferred knowingly or unwittingly from the mainland to the same islands.

Current situation in 2017 A total of 42 islands within the Marlborough Sounds are thought to be free of any established brushtail possum population.

There continues to be reports of possum sightings.

• In November 2011, a report was received of a possum sighting on Rangitoto ki te Tonga/D’Urville Island. This was investigated by Council and the Department of Conservation with no further evidence found.

• In 2013, Department of Conservation staff sighted an adult possum on Blumine Island. Trapping and surveillance by the Department of Conservation discovered and destroyed another adult possum and two juveniles. It is not known how these possums came to be present on Blumine Island. It is suspected they were illegally released.

• More recently, in late 2016, there was a report of possum calling on Arapaoa Island. The resulting response by the Department of Conservation found no evidence.

Options to respond to brushtail possum Baseline: No RPMP In this scenario no specific response or management occurs over and above any existing asset protection control work.

Control option(s): Exclusion Programme: In which the intermediate outcome for the programme is to prevent the establishment of the subject that is present in New Zealand but not yet established in an area.

Level of analysis for brushtail possum Council has determined that a low level of analysis be undertaken for possums. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.

Impacts The possum originates from Australia. It was released in New Zealand in the late 1800s to establish a fur trade similar to that flourishing in Australia at the time. Possums selectively browse preferred plant species. They cause extensive canopy defoliation in native forest. They also cause economic damage in exotic forest plantations. Possums will prey on ground and tree nesting birds and their eggs. The possum is a recognised vector in the spread of the disease bovine tuberculosis to domestic livestock. Populations of the possum exist in New Zealand’s North, South and Stewart Islands.


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Defoliation of native flora, competition for resources and predation upon vulnerable fauna present of the islands.

26,599 hectares of islands in the Marlborough Sounds area are free from possums. A subset of those islands making up 1,080 hectares are also completely pest-free, including rodents. These are: • Stephens / Takapourewa • Whakaterepapanui • Puangiangi • Tinui • Trios • Chetwodes • Maud / Te Hoiere • Titi • Motuara • Long • Pickersgill • Blumine • North Brother If possums were to establish on any or all of these islands, there would be significant impact on not only the native flora and fauna that would normally be present on these islands, but also the immense value these islands hold as breeding sanctuaries for populations under threat at other locations around New Zealand.








Regional community




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Benefit Option

No RPMP Exclusion

The prevention of impacts associated with possums establishing on any or all of the currently possum-free islands.

No programme cost The benefit under an Exclusion Programme is maximised from the outset and kept at that level throughout the life of the Plan.


Programme Costs Option


Exclusion Annual cost (excl GST)

Council costs • Surveillance • Response • Administration • Education/awareness

- DOC$25,000* MDC$6,000*


Total - $31,000*

Costs of effects on values Low, but increases exponentially over time

Insignificant

* In the event a response is required. Will not be included in cost allocation anlaysis Note: There are no additional cost measures proposed for surveillance given existing Department of

Conservation works and passive surveillance is already in place.



Rationale for the allocation of costs It has been recognised that the majority of offshore islands in the Marlborough Sounds are entirely Department of Conservation estate. However, the majority of land on the larger islands is privately owned. Because of this mix of land tenure, the Department of Conservation wishes to co-manage this species with Council to provide ‘across-the-board’ protection for the islands. As such, a portion of the cost of the programme has been allocated to the Department of Conservation. This is in recognition of the Department of Conservation being a major beneficiary.



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Level of Risk

Option

No RPMP Exclusion

N/A Low-Moderate

Reason Technologies and methods to carry our effective surveillance and control brushtail possums are readily available. The mainland surrounding or near to many of the possum-free islands commonly holds large possum numbers. This can increase the risk that natural dispersion to the islands may occur.


Most preferred option Exclusion Programme


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7.6 Bur daisy (Calotis lappulacea) Why is it a threat? Bur daisy is an erect perennial herb, which originates from Australia. It grows up to 30 centimetres high and has small yellow flower heads, which form spiny burs. It displaces desirable pasture species and the spiny burs contaminate wool. It has the potential to spread throughout Marlborough’s dry grassland country.

Reasons for proposing a Plan Bur daisy has in the past been classified as a noxious plant then subsequently as a pest under early Regional Pest Management Strategies. It has been actively managed by Council and former authorities. There has only been one property in Marlborough that has been identified as having an infestation of bur daisy. The level of infestation on that property has dramatically reduced to a point where intensive searching is now only finding a small number of plants per year. This demonstrates the importance of vigilance associated with a structured programme within a Plan.

There is a significant net benefit to the control of bur daisy based on the potential for damage to Marlborough’s pastoral farming economy.

Why the Plan is more appropriate than relying on voluntary actions If control was left to the voluntary actions of occupiers and no dedicated control was undertaken, then the plant would build in density on the infested property and likely result in spread throughout the region. It would ultimately result in impacts to the pastoral industries that rely on sheep. The inclusion of bur daisy in the Plan will ensure this pest plant is kept under control and managed to zero density.

7.6.1 Objectives 7.6.1.1 By 2035, bur daisy (Calotis lappulacea) will be controlled to zero density, where no plants

are found in the preceding 5 years, in the Marlborough district to prevent adverse effects on the economy.

7.6.1.2 By the end of the term of this Plan, bur daisy (Calotis lappulacea) will only be found at densities less than or equal to 0.05 plants per man hour effort in the Marlborough district to prevent adverse effects on the economy.






a) Delivering a service to control bur daisy in liaison with the occupier.









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Council may:






7.6.2 Rules Rule 7.6.2.1 Occupiers are required to notify Council of any new infestation of bur daisy (Calotis lappulacea) on land that they occupy.











7.6.3 Analysis of the benefits and costs for bur daisy Background Bur daisy became a Total Control pest plant in the Regional Pest Management Strategy for Marlborough in 1996.

It is only known to be present on one property in the lower Waihopai Valley. Infestations at this site were extensive in the mid-1990s. In 1999, 12,500 plants were sprayed with the herbicide. Up until 2002 a contractor used knapsack spraying as the preferred method of control. Seedling numbers have declined substantially since 2002 and now a contractor grubs and bags any plants and then spreads prills over the area for residual control.

Council has controlled bur daisy infestations annually since 1996. In 2001 an impact and economic analysis was undertaken to justify its continued inclusion in the Regional Pest Management Strategy for Marlborough 2001.

Bur daisy continued to be included in the Regional Pest Management Strategy for Marlborough 2007 and is declared a Total Control pest plant in the current Regional Pest Management Strategy for Marlborough 2012.


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Current situation in 2017The single property in the lower Waihopai Valley remains as the only known site of bur daisy in Marlborough.

This property is visited annually and ranged thoroughly. In recent years, the number of plants found has been consistently less than 50. Whilst trending downward, it is believed the longevity of the seed burs will mean emergence of new plants will continue for many years. However, the ranging carried out by Council staff and/or contractors is very thorough and is timed to prevent new burs from forming.

Figure 5: The trend in infestation levels of bur daisy in Marlborough

Options to respond to bur daisyBaseline: No RPMPNo RPMP: In this scenario no control of bur daisy is undertaken, and the assumption is made that the plant becomes well-established and progresses toward full naturalisation in all susceptible areas in the long term.

Control option(s):Eradication Programme: In which the intermediate outcome for the programme is to reduce the infestation level of the subject to zero levels in an area in the short to medium term.

This programme would most closely align to the current Total Control programme in the Regional Pest Management Strategy for Marlborough 2012.

Continue the bur daisy programme as an Eradication Programme given the single site, the lower number of plants being found, and a through ranging operation each year timed to prevent new seed entering the system.

Level of analysis for bur daisyCouncil has determined that a low level of analysis be undertaken for bur daisy. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.

ImpactsBur daisy is an erect perennial herb, which originates from Australia. It grows up to 30 centimetreshigh and has small yellow flower heads, which form spiny burs. It displaces desirable pasture species and the spiny burs contaminate wool. It has the potential to spread throughout Marlborough’s dry grassland country.


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Economic The economic impacts of bur daisy are likely to occur to landholders in the dry pastoral areas of Marlborough. Diminished pasture and livestock production.

Control of bur daisy will prevent damage to 210,000 hectares of pastoral habitat. It is estimated that bur daisy will infest pastoral and tussock land covers, including up to 10% of hill country land uses (LUC Classes IV and V ), and 5% of high country land (Class VI). Modelling of this scenario assumed spread characteristics of between 1 and 10 kilometres for mature plants, and between 30 and 60 years to reach its maximum density at a site in an uncontrolled situation.







Regional community




Benefit Option

No RPMP Eradication

The prevention of bur daisy infesting new areas and the resulting impact of that on pastoral production values.

No programme cost The values protected by the control of bur daisy are largely pastoral production values. The eradication of bur daisy will prevent damage to 210,000 hectares of pastoral habitat. The benefit under an Eradication Programme will increase to an end point when the objective is able to be achieved.


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Eradication Annual cost (excl GST)


- $6,100


Total - $6,100


Insignificant





Level of Risk

Option

No RPMP Eradication

N/A Medium

Reason Bur daisy is very limited in distribution. Council will continue to visit the site where plants continue to be found, undertake control, and search surrounding areas. Given there are so few active sites, they are readily accessible the level of risk is not high. However, it is evident the seed is long-lived and the plants that have been found are scattered over a large, steep hillside. This results in the residual operational risk being not low.


Most preferred option Eradication Programme


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7.7 Cathedral bells (Cobaea scandens) Why is it a threat? Cathedral bells is a climbing perennial evergreen vine which can grow to 6 metres. The plant originates from Central and South America. The vine has distinctive large round deep purple lantern like flowers. The fruit are large and oval from 6-10 centimetres long and release winged seeds. The plant is susceptible to frost and heavy shading. Occasionally plants will root from nodes on the stems where they touch the ground. Seed is dispersed by wind over short distances and can be spread by fragments or seed in water, gravel or soil over large distances. It has the potential to become a major weed in a variety of habitats where it will displace native species.

Reasons for proposing a Plan Cathedral bells has long been recognised as a highly invasive weed in natural ecosystems with the potential to become the next smothering vine in Marlborough’s ecosystems. Localised infestations exist throughout New Zealand where it is, in most parts, under intensive management by authorities or community groups.

Infestations in Marlborough are limited to nine sites, with only three of which are active infestations. Unfortunately, like many weed species, complete removal is a long and arduous task, with some of the three remaining sites harbouring a large number of seedlings each year.

Why the Plan is more appropriate than relying on voluntary actions With so few known sites, the management of this species needs to be both strategic and intensive. Because of this, it is more appropriate to be managed through a structured programme of delivery enabled by a Plan rather than relying on voluntary actions.

7.7.1 Objective Over the duration of the Plan, control cathedral bells (Cobea scandens) in the Marlborough district to less than or equal to 2016 levels to minimise adverse effects on the environment and enjoyment of the natural environment.






a) Delivering a service in conjunction with the Department of Conservation to manage cathedral bells.





a) Land owners and/or occupiers or other persons may be required to act where rules or statutory obligations dictate:

i) The presence of pests is to be reported.

ii) Pests are not to be spread (propagated, sold or distributed).


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Council may:






7.7.2 Rules Rule 7.7.2.1 Occupiers are required to notify Council of any new infestation of cathedral bells (Cobea scandens) on land that they occupy within 5 working days of the initial observation.



Explanation of the rule: The purpose of this rule is for occupiers to assist Council with surveillance. Having occupiers notifying Council of new sites and plants on their properties in addition to Department of Conservation surveillance will assist Council in achieving the objective of the programme. New infestations will be able to be controlled and incorporated into the programme.








7.7.3 Analysis of the benefits and costs for cathedral bells Background In 2006, cathedral bells was known to occur at seven sites - all in the Marlborough Sounds area. Department of Conservation staff began undertaking control work, under a joint initiative with Council, at all known sites during that same year.

Further weed survey work carried out by the Department of Conservation in the Marlborough Sounds resulted in the discovery of two new sites.

With a good suite of information, an impact and economic analysis was undertaken in 2006. As a result cathedral bells was included as a Total Control Pest plant in the Regional Pest Management Strategy for Marlborough in 2007.

Since then, under a continuing joint initiative, Department of Conservation staff visit all known sites of cathedral bells each year. All large plants found are controlled by cutting and treating with herbicide gel and all seedlings found are hand pulled.


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Cathedral bells is a Total Control pest plant in the Regional Pest Management Strategy for Marlborough 2012.

Current situation in 2017There are currently nine sites of cathedral bells that are currently being managed in Marlborough. Only three of these sites are active (plants still being found) while the others are under a longer term monitoring programme (termed historical) after plants have been successfully eradicated.

Department of Conservation staff visit all known active sites of cathedral bells each year, and a portion of historical sites. All large plants found are controlled by cutting and treating with a gel and all seedlings are hand pulled.

Figure 6: The trend in infestation levels of cathedral bells in Marlborough

Options to respond to cathedral bellsBaseline: No RPMPIn this scenario no control of cathedral bells is undertaken, and the assumption is made that the plant becomes well-established and progresses toward full naturalisation in all susceptible areas in the long term.




Level of analysis for cathedral bellsCouncil has determined that a low level of analysis be undertaken for cathedral bells. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.


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Impacts Cathedral bells is a climbing perennial evergreen vine which can grow to 6 metres. The plant originates from Central and South America. The vine has distinctive large round deep purple lantern like flowers. The fruit are large and oval from 6-10 centimetres long and release winged seeds. The plant is susceptible to frost and heavy shading. Occasionally plants will root from nodes on the stems where they touch the ground. Seed is dispersed by wind over short distances and can be spread by fragments or seed in water, gravel or soil over large distances.


Conservation values It has the potential to become a major weed in a variety of habitats where it will displace native species. Smothers and displaces native vegetation.

60,000 hectares of habitat at risk.








Regional community




Benefit Option


The prevention of cathedral bells infesting new areas and the resulting impact of that on environmental values.




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Costs of each option The operational programme will be very similar to the current programme.

Programme Costs

Option


GST)


GST)


GST)


- MDC $5,000+ DOC $15,000+

MDC $200 DOC $1,500


Total - $20,000+ $1,700


over time




Rationale for the allocation of costs It has been recognised that due to the location of the infestations of cathedral bells in Marlborough, the Department of Conservation wishes to co-manage this species. As such, the majority of the cost of the programme has been allocated to the Department of Conservation. This is in recognition of the Department of Conservation being major beneficiary of this programme.



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Level of Risk

Option


N/A High Low

Reason The level of risk of not achieving an eradication objective, within 10 years or even at a longer time scale, is very high. The current number of plants still being destroyed at known sites along with the prolific reproductive capabilities of cathedral bells means an eradication objective is not feasible in the short to medium term and possibly not even in the long term.

By visiting all known active sites each year, and placing the remainder under longer term surveillance, Council will be able to maintain and possibly continue to see a decline in numbers of plants over the next 10 years.




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7.8 Chilean needle grass (Nassella neesiana) Why is it a threat? Chilean needle grass (CNG) is highly invasive, exhibits high reproductive rates, rapid growth and high climatic and soil tolerance. It quickly forms dense cover over large areas which exclude preferred pasture species. This reduces the productivity of the land for pastoral farmers through direct impact on livestock and the limitations imposed to minimise further spread of the species. Chilean needle grass can also pose a threat to natural tussock and grassland ecosystems.

Chilean needle grass flowers between November and April. A Chilean needle grass adult plant is unpalatable to stock during the flowering period. Chilean needle grass is capable of producing seed by three means:

1. Aerial seeds;

2. Stem seeds; and

3. Basal seeds (cleistogenes).

The aerial seeds have sharp tips, which can bore into the eyes and pelts of animals. The seeds penetrate wool and reduce agricultural capability within the region.

Chilean needle grass seed is not readily spread by wind but is easily spread by machinery, livestock, hay, waterways and people.

Reasons for proposing a Plan In comparison to other established pest species, Chilean needle grass is still relatively confined in distribution within Marlborough. There remains an ongoing major threat of Chilean needle grass getting into hill and high country pastoral systems.

The reason for proposing to manage Chilean needle grass within a Plan is to provide for a baseline framework for management with supporting regulations to ensure future impacts are avoided.

Why the Plan is more appropriate than relying on voluntary actions If control was left to the voluntary actions of occupiers, and a choice was made by some occupiers to not undertake control, there is a real risk that adequate management across the region would not occur. The inclusion of a programme for Chilean needle grass in the Plan will ensure this pest plant is kept under management across the region in accordance with a region-wide programme.

7.8.1 Objective Over the duration of the Plan, control Chilean needle grass (Nassella neesiana) in the Marlborough district to less than or equal to baseline levels* to minimise adverse effects on economic wellbeing, the environment and enjoyment of the natural environment.

*A baseline assessment will be made either prior to or immediately after the Plan commences.






a) Delivering a service to control Chilean needle grass, in liaison with the occupier.

b) Carrying out inspections to ensure occupiers are meeting obligations.


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a) Certain high spread risk activities are regulated.



Council may:






7.8.2 Rules Rule 7.8.2.1 Occupiers shall destroy all Chilean needle grass (Nassella neesiana) plants, on land that they occupy, each year before they produce seed, unless a management plan* approved by Council is in place.


*A management plan for the purposes of Rule 7.8.2.1 is an agreed plan between the occupier and Council that outlines how Chilean needle grass will be managed on the land they occupy and contain administration provisions relating to the maintenance of the plan.

For clarity purposes, a minimum requirement (but may not be the only requirement) for management plans approved by Council for Chilean needle grass will be the annual destruction of plants within 20 metres of property boundaries, except on boundaries with other heavily infested properties.

Approved management plans will be dynamic and available to the occupier for reference at any time via the online Property File system at Council.

Rule 7.8.2.2 No person shall move sheep from a property with a known infestation of Chilean needle grass (Nassella neesiana), unless:

1. The sheep are being transported directly to slaughter, or

2. The sheep were solely grazed in an unaffected area of the property, as agreed to by Council.


Rule 7.8.2.3 No person shall move cattle from a property with a known infestation of Chilean needle grass (Nassella neesiana), unless:

1. The cattle were solely grazed in an unaffected area of the property, as agreed to by Council, or

2. The movement is taking place between 1 April and 30 September, and


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3. The movement is taking place when ground conditions are dry, and

4. The cattle are stood down (to empty out), for 12 hours prior to movement.

And, a record is kept for a minimum period of 5 years from the date of movement that details the steps taken to meet the rule requirements.


Rule 7.8.2.4 No person shall move any hay or other stock feed/arable crop product off a property containing a known infestation of Chilean needle grass (Nassella neesiana), unless the hay or any other stock feed/arable crop has originated from an unaffected area of the property, as agreed to by Council.


Rule 7.8.2.5 No person shall move any machinery off a property containing a known infestation of Chilean needle grass (Nassella neesiana), unless:

1. The machinery has been cleaned on the originating property to a standard where there is no visible soil or organic matter; and

2. The machinery has been inspected by a person approved by Council to inspect machinery for the purposes of this rule; or

3. The machinery has been operating within an unaffected area of the property, as agreed to by Council.


Rule 7.8.2.6 No person shall move any domestic animal (excluding sheep and cattle) off a property containing a known infestation of Chilean needle grass (Nassella neesiana) that is carrying seed or plant parts of Chilean needle grass.


Rule 7.8.2.7 Occupiers are required to notify Council of any new infestation* of Chilean needle grass (Nassella neesiana) on land that they occupy within 5 working days of the initial observation.


* Current distribution data is able to be viewed online via Council’s Smart Maps service.

Explanation of the rules: The purpose of Rule 7.8.2.1 is in accordance with section 73(5)(h) in that all occupiers within an infestation of Chilean needle grass are being required to take specified actions to prevent the pest establishing on that land.

The purpose of Rules 7.8.2.2 to 7.8.2.6 are in accordance with section 73(5)(e) in that activities that may be at risk of introducing Chilean needle grass into new unaffected areas of Marlborough are regulated as the constant threat of movement via contaminated goods will affect the implementation of the Plan.




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7.8.3 Exemptions Attention is specifically drawn to the process of exemptions that could apply to any rule within the proposed Plan. Upon receipt on of application, it will be considered by Council in accordance with the process outlined in section 9.

7.8.4 Analysis of the benefits and costs for Chilean needle grass

Background Chilean needle grass has been in Marlborough since the 1930s and has long been managed as a pastoral threat. In recent years, Chilean needle grass has entered somewhat of an exponential phase of being detected on new properties. Over the period from 2005 to 2017, the number of affected properties increased from 92 to 170.

Chilean needle grass is a very hard to control perennial tussock and once established in an area it is very difficult to remove. This is even more so if hill country inaccessible to ground-based machinery becomes infested.

Current situation in 2017 There are 170 properties in Marlborough with a known infestation of Chilean needle grass. The nature of infestation varies greatly across these properties with 101 of these properties having a relatively low level infestation under intensive management. In total, approximately 2800 hectares of land in Marlborough is affected.

Options to respond to Chilean needle grass Baseline: No RPMP In this scenario it is assumed that no control is undertaken




Level of analysis for Chilean needle grass Council has determined that a medium level of analysis be undertaken for Chilean needle grass. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.

Impacts Chilean needle grass is highly invasive, exhibits high reproductive rates, rapid growth and high climatic and soil tolerance. It quickly forms dense cover over large areas which exclude preferred pasture species. This reduces the productivity of the land for pastoral farmers, while Chilean needle grass can pose a threat to our tussock and grassland ecosystems.

Chilean needle grass flowers between November and April. A Chilean needle grass adult plant is unpalatable to stock during the flowering period. Chilean needle grass is capable of producing seed by three means:

1. Aerial seeds;

2. Stem seeds; and

3. Basal seeds (cleistogenes).


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The aerial seeds have sharp tips which can bore into the eyes and pelts of animals. The seeds penetrate wool and reduce agricultural capability within the region.

Chilean needle grass seed is not readily spread by wind but is easily spread by machinery, stock, hay, waterways, feral animals and people.

There is a major threat of Chilean needle grass getting into high country pasture in Marlborough.



See Appendix (3.1).

Animal welfare The sharp penetrating seed of Chilean needle grass is well known to readily attach to livestock, in particular sheep. The backward pointing hairs and corkscrew awn sees the seed easily penetrating hides. Seeds have been shown to penetrate muscle causing abscess but also cases of blindness where seeds have penetrated in the eye region on animals.

Social and recreational values There are two key impacts on social and recreational values. Firstly, the seeds will readily attached to clothing and are sharp enough to cause wounds to human skin. Secondly, through management approaches and associated restrictions, the use of infested areas can be restricted by authorities. This has a negative impact on the availability of areas to actively recreate within. Within Marlborough, this has already occurred in that the management on an infestation near Omaka caused serious disruption to the parking plans for a large public event nearby.








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Benefit Option


The prevention of Chilean needle grass infesting new areas and the resulting impact of that on pastoral production values.

No programme cost The values protected by the control of Chilean needle grass are largely pastoral production values. The eradication of Chilean needle grass will prevent damage to 380,000 hectares of pastoral habitat. The benefit under an Eradication Programme will increase to an end point when the objective is able to be achieved.

The values protected by the control of Chilean needle grass are largely pastoral production values. The eradication of Chilean needle grass will minimise damage to 380,000 hectares of pastoral habitat. The benefit under a Sustained Control Programme will remain constant throughout the life of the Plan, with no end point.

The prevention of Chilean needle grass infesting new areas and having greater impacts on animal welfare.

The benefit under an Eradication Programme will increase to an end point when the objective is able to be achieved.


The prevention of Chilean needle grass infesting new areas and increasing the impact on social and recreational values.

The benefit under an Eradication Programme will increase to an end point when the objective is able to be achieved.



Programme Costs

No RPMP Per Annum

Eradication (Council service

delivery, handover to occupier) Per annum

Sustained Control (Council service

delivery, in conjunction with

occupier) Per annum

Council costs • Administration • Education/awareness

- $300,000+ $150,000

Council Costs • Service Delivery • Programme

monitoring

$1,200,000+ $250,000


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Land occupier costs - $700,000 $350,000

Total - $2,200,000 $750,000

Costs of effects on values -$65,062,046 Insignificant

Analysis An analysis has been carried out using the economic impacts of Chilean needle grass to pastoral systems - see Appendices 2.1, 2.2 and 2.3. A summary and sensitivity analysis can be found below in Tables 3 and 4.

Discount rate: As part of the economic analysis, a discount rate of 4% has been used.

In previous analyses for benefits and costs associated with regional pest management, the recommended Treasury (previously 8%, now 6%7) has been used. However, the nature of the investment with pest management programmes can be likened to that outlined by Chris Parker writing in a New Zealand Institute of Economic Research Insight8. In that paper, a social discount rate was discussed that suggests with long term impacts that matter projects (i.e. an RPMP programme) should consider using a ‘social’ discount rate of 3-3.5%.

As a result, a conservative discount rate of 4% has been used by Council in the analyses supporting the applicable proposed programmes. This is less than that recommended by Treasury but, considering the long term impacts of pest management programmes, the lower discount rate is more appropriate.

Table 3: Summary of economic analysis for Chilean needle grass

Level of Risk

Options

No RPMP Eradication (Council service


occupier)



occupier)

Present Value Net Present Value Net Present Value

N/A High Moderate-Low

Present Value/Net Present Value (PV/NPV) (4% discount rate)

$-103,665,523 $61,612,846 $76,036,753

Probability of success (risk) 100% 20% 80%

Risk adjusted PV/NPV (4%) $-103,665,523 $-16,712,720 $56,455,361

7 Treasury, NZ. 2016. Public sector discount rates for cost beenfit analyses. Accessed 22 September 2017. http://www.treasury.govt.nz/publications/guidance/planning/costbenefitanalysis/currentdiscountrates

8 Parker, C. 2011. Ecomics like there’s no tomorrow. NZIER Insight 32/2011.


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Table 4: Sensitivity analysis

Level of Risk

Options



occupier)



occupier)


High Low-Moderate

Risk adjusted PV/NPV (3%) - NZIER Social rate $-144,570,805 $-13,092,425 $83,944,393

Risk adjusted PV/NPV (4%) $-103,665,523 $-16,712,720 $56,455,361

Risk adjusted PV/NPV (6%) - Default Treasury rate $-56,138,861 $-19,144,744 $25,484,402

Risk adjusted PV/NPV (4%) High impact - 55% reduction in production

$-142,540,094 $-9,695,639 $83,667,986

Risk adjusted PV/NPV (4%) Baseline - 40% reduction in production

$-103,665,523 $-16,712,720 $56,455,361

Risk adjusted PV/NPV (4%) Low impact - 25% reduction in production

$-64,790,952 $-23,729,801 $29,242,736

Proposed allocation of costs It is proposed that the approximately half of the programme costs are allocated to occupiers of land that have Chilean needle grass infestations. This has been done by way of rules requiring the occupiers to manage Chilean needle grass.





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Risk that each option will not achieve the objective The supporting information document to this Proposal contains information to support this analysis. These risks were translated to weighing figures used as part of the economic analysis.

Level of Risk

Option


N/A High Low-Moderate

Reason High Biologically, Chilean needle grass is very difficult to completely remove from an area where it has been growing and seeding for a number of years. Large areas of the infestations within Marlborough fall within this category. As a result, setting an eradication objective for this species (to a point where no plants are found over time) carries a high risk.

Low-Moderate Biologically, Chilean needle grass is very difficult to completely remove from an area where it has been growing and seeding for a number of years. Large areas of the infestations within Marlborough fall within this category. However, there have been ongoing improvements in the ways to suppress populations through integrated pest management. As a result, the risk of not achieving a sustained control objective is low-moderate.




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7.9 Chinese pennisetum (Pennisteum alpecuroides) Why is it a threat? Chinese pennisetum is a perennial, tufted grass that originates from Eastern Asia. It will grow up to 1 metre high and has purple seed heads, which look like small bottlebrushes. It spreads using seed, which attaches itself to passing animals. It is capable of forming dense mats and is unpalatable to stock. Chinese pennisetum prefers higher rainfall areas and has the potential to invade large areas of Marlborough.

Reasons for proposing a Plan Chinese pennisetum has been under management in Marlborough for a number of years. The levels of infestations are now very low.

There is a significant net benefit to the control of Chinese pennisetum based on the potential for damage to Marlborough’s pastoral farming economy and the potential to displace Marlborough’s native species.


7.9.1 Objective Over the duration of the Plan, control Chinese pennisetum (Pennisetum alpecuroides) in the Marlborough district to less than or equal to 2016 levels to minimise adverse effects on economic wellbeing, the environment and enjoyment of the natural environment.






a) Delivering a service to control Chinese pennisetum in liaison with the occupier.









Council may:




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7.9.2 Rules Rule 7.9.2.1 Occupiers are required to notify Council of any new infestation of Chinese pennisetum (Pennisetum alpecuroides) on land that they occupy within 5 working days of the initial observation.











7.11.3 Analysis of the benefits and costs for Chinese pennisetum

Background Chinese pennisetum became a containment control pest plant in the Regional Pest Management Strategy for Marlborough in 1996. Occupiers were responsible for its control. Very few notices of direction were issued over the next 10 years as most occupiers complied with their control programmes.

Because plant numbers had reduced significantly by 2006, the status of Chinese pennisetum was reviewed to coincide with a review of the Regional Pest Management Strategy in 2006. An impact and economic analysis in 2006 confirmed that the status of Chinese pennisetum be changed from a Containment Control pest plant to a Total Control pest plant in the 2007 Regional Pest Management Strategy for Marlborough.

Chinese pennisteum was a Total Control pest plant in the Regional Pest Management Strategy for Marlborough 2012.

Current situation in 2017 There are three main areas in Marlborough with infestations of Chinese pennisetum. These are Port Underwood, the Onamulutu Valley and a property at Okaramio. The majority of plants are being found on a property at Ocean Bay in Port Underwood.

Out of the 53 sites, only 10 are under active management annually with the remaining 43 sites under longer term surveillance.


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Figure 7: The trend in infestation levels of Chinese pennisetum in Marlborough

Options to respond to Chinese PennisetumBaseline: No RPMPIn this scenario no control of Chinese pennisetum is undertaken, and the assumption is made that the plant becomes well-established and progresses toward full naturalisation in all susceptible areas in the long term.



2. Sustained Control: In which the intermediate outcome for the programme is to provide for ongoing control of the subject, to reduce its impacts on values and spread to other properties.

Level of analysis for Chinese PennisetumCouncil has determined that a low level of analysis be undertaken for Chinese pennisetum. The justification for this decision is documented in the supporting information document to this Proposal.That document also contains information about the risks that the objectives will not be reached.

ImpactsChinese pennisetum is a perennial, tufted grass that originates from Eastern Asia. It will grow up to 1 metre high and has purple seed heads, which look like small bottlebrushes. It spreads using seed, which attaches itself to passing animals. It is capable of forming dense mats and is unpalatable to stock. Chinese pennisetum prefers higher rainfall areas and has the potential to invade large areas of Marlborough.


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Economic The economic impacts of Chinese pennisetum are likely to occur to pastoral landholders in Marlborough’s higher rainfall areas. Diminished pasture and livestock production.

Control of Chinese pennisetum will prevent damage to 265,000 hectares of pastoral habitat. It is estimated that Chinese pennisetum will infest pastoral and tussock land covers, including 5% of intensive pastoral land uses (LUC classes I, II and III) and up to 10%9 of all hill/high country pastoral land uses (LUC Classes IV, V, and VI ). Modelling of this scenario assumed spread characteristics of between 50 and 200 metres, and new sites are established annually from spread through machinery, hay, animals, etc10, and the plant takes between 30 and 60 years to reach its maximum density at a site in an uncontrolled situation.








Regional community



9 While its impact in higher rainfall areas will be greater than this, the figure of 10% reflects the fact that much of this land class is lower rainfall area.

10 This approximately reflects the rate of establishment of sites since its introduction. The number of new sites established are proportional to the current area displaced by the plant - at current displacement one new site is established annually.


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Benefit Option


The prevention of Chinese pennisetum infesting new areas and the resulting impact of that on pastoral production values.

No programme cost The values protected by the control of Chinese pennisetum are largely pastoral production values. Control of Chinese pennisetum will prevent damage to 265,000 hectares of pastoral habitat. The benefit under an Eradication Programme will increase to an end point when the objective is able to be achieved.

The values protected by the control of Chinese pennisetum are largely pastoral production values. Control of Chinese pennisetum will prevent damage to 265,000 hectares of pastoral habitat. The benefit under a Sustained Control Programme will remain constant throughout the life of the Plan, with no end point.


Programme Costs

Option



GST)


GST)


- $40,000+ $9,000


Total - $40,000+ $9,000


over time






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Level of Risk

Option


N/A High Low

Reason The level of risk of not achieving an eradication objective, within 10 years or an even longer time scale is very high. Chinese pennisetum has been intensively managed for over 20 years. Initially by landholders and then by Council. While there has been a dramatic decline, it has shown the difficult nature in completely eradicating an established pest plant species.

There is a lower level of risk that Council will be able to maintain a very low density of Chinese pennisetum in Marlborough. This will be achieved by ongoing control at sites and with structured surveillance of all known sites and other risk areas over time.




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7.10 Climbing spindleberry (Celastrus orbiculatus) Why is it a threat? Climbing spindleberry is a vigorous climber, which originates from Eastern Asia. It has the ability to kill trees by smothering them due to its shade tolerance and rampant growth. Birds will disperse its seed into remote areas. It has a bad record overseas, causing major problems in plantation forests and natural areas of Eastern Asia.

Reasons for proposing a Plan Climbing spindleberry has long been recognised as a highly invasive weed in natural ecosystem with the potential to become the next smothering vine in Marlborough’s ecosystems. Localised infestations exist throughout New Zealand where it is, in most parts, under intensive management by authorities or community groups.

Infestations in Marlborough are limited to six sites, with only one of which active. Unfortunately, like many weed species, complete removal is an arduous task.


7.10.1 Objective By the end of the term of this Plan, climbing spindleberry (Celastrus orbiculatus) on all known sites in the Marlborough district will have been controlled to zero density to prevent adverse effects on the environment, and enjoyment of the natural environment.






a) Delivering a service to control climbing spindleberry in liaison with the occupier.









Council may:




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7.10.2 Rules Rule 7.10.2.1 Occupiers are required to notify Council of any new infestation of climbing spindleberry (Celastrus orbiculatus) on land that they occupy within 5 working days of the initial observation.











7.10.3 Analysis of the benefits and costs for climbing spindleberry

Background During a review of the 1996 Regional Pest Management Strategy for Marlborough, the Department of Conservation highlighted their concerns about the discovery of this invasive weed at several sites in the Marlborough Sounds. Council staff worked with Department of Conservation staff to carry out survey work to establish the distribution of climbing spindleberry. An impact and economic analysis was undertaken for climbing spindleberry in 2001.

As a result climbing spindleberry was included in the Regional Pest Management Strategy for Marlborough 2001 as a Total Control Pest plant.

All known infestations of climbing spindleberry have been annually managed by Department of Conservation staff in November. The vines are cut and the stumps are treated with Vigilant® Gel. Seedlings are pulled by hand or sprayed.

In 2007/2008 several new infestations have been found growing near the original sites that were not identified in the original survey work.

Climbing spindleberry is a Total Control pest plant in the Regional Pest Management Strategy for Marlborough 2012.


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Current situation in 2017There are six sites in Marlborough where plants have been found. These are all in the Marlborough Sounds area. The Department of Conservation continues to visit five of these sites annually to undertake the control work with the aim of destroying all plants found. The remaining sixth site is visited under a longer time scale surveillance programme.

Recent plant numbers have shown a steady decline with an average of less than six plants being destroyed in recent years.

Figure 8: The trend in infestation levels of climbing spindleberry in Marlborough

Figure 9: The trend in infestation levels of climbing spindleberry in Marlborough, in the last 5 years

Options to respond to climbing spindleberryBaseline: No RPMPIn this scenario no control of climbing spindleberry is undertaken, and the assumption is made that the plant becomes well-established and progresses toward full naturalisation in all susceptible areas in the long term.


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Control option(s): Eradication Programme: In which the intermediate outcome for the programme is to reduce the infestation level of the subject to zero levels in an area in the short to medium term.

This programme would most closely align to the current Total Control programme in the Regional Pest Management Strategy for Marlborough 2012.

Level of analysis for climbing spindleberry Council has determined that a low level of analysis be undertaken for climbing spindleberry. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached and additional information for the cost allocation analysis that has been used to support the analysis presented below.

Impacts Climbing spindleberry is a vigorous climber, which originates from Eastern Asia. It has the ability to kill trees by smothering them due to its shade tolerance and rampant growth. Birds will disperse its seed into remote areas. It has a bad record overseas, causing major problems in plantation forests and natural areas of Eastern Asia.


Conservation values Smothers native vegetation.

It is assumed that over time it will spread and occupy up to 10 % of 198,000 hectares of forest edge and forest habitats in Marlborough.








Regional community




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Benefit Option

No RPMP Eradication

The prevention of climbing spindleberry infesting new areas and the resulting impact of that on environmental values.







- MDC $200 DOC $1,800


Total - $2,000


Insignificant



Rationale for the allocation of costs It has been recognised that due to the location of the infestations of climbing spindleberry in Marlborough, the Department of Conservation wishes to co-manage this species. As such, the majority of the cost of the programme has been allocated to the Department of Conservation. This is in recognition of the Department of Conservation being major beneficiary of this programme.



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Level of Risk

Option

No RPMP Eradication

N/A Moderate

Reason Based on the current distribution and the decline in the number of plants required to be controlled, achieving zero levels of climbing spindleberry under an Eradication Programme would be achievable.




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7.11 Contorta pine (Pinus contorta) Why is it a threat? Contorta pine can have significant impacts on native ecosystems, particularly those low in stature, such as tussock and indigenous grasslands, alpine ecosystems and subalpine scrub. Contorta pine grows faster and taller than low-stature vegetation so can easily out-compete these species. Soil and soil fauna are also altered when wilding conifers replace native ecosystems.

Contorta pine can also adversely affect amenity and landscape values. These landscapes are important for tourism and large scale landscape changes can impact on the value gained from tourism in Marlborough.

In areas where there is long term, seasonal soil moisture deficits, dense contorta pine stands can contribute to reductions in surface water flows, potentially impacting on water availability and associated aquatic ecosystems.

All the impacts outlined above can adversely affect values held by iwi in the Top of the South.

In areas of extensive pastoral farming, contorta pine infestations adversely impact economic wellbeing by reducing available grazing and limited the options for future land use.

Reasons for proposing a Plan In Marlborough, it is recognised the first up task of managing contorta pine to sustainable levels is one best carried out through large scale collaborative programmes outside of the Plan. However, to ensure the achievements gained by investing in management (by a number of parties), a programme within a Plan can ensure the gains made are sustainable in the long term. As such, the proposed programme reflects this.

Why the Plan is more appropriate than relying on voluntary actions In essence, the previously mentioned collaborative management projects are voluntary actions. Interested parties, including Council, the Department of Conservation, the Ministry for Primary Industries (MPI), Land Information New Zealand, the community at large and other organisations recognise the importance of managing contorta pine. This culminated in the development of the New Zealand Wilding Conifer Management Strategy (2015) then subsequent Crown Funding administered by MPI to invest in the issue (the National Wilding Conifer Management Programme). Prior to this, local trusts, such as the Marlborough Sounds Restoration Trust and South Marlborough Landscape Restoration Trust, established through a community desire to take action for community good.

All of these aspects to contorta pine management is occurring under the banner of voluntary action.

However, management of contorta pine is a long game. Under all of the scenarios of intervention, there is a concern that up-front investment could be put at risk by a lack of voluntary actions being undertaken at an individual land occupier level. As such, it is proposed that this Plan acknowledges the success of voluntary action in one respect (the broad collaborative management approaches), but the Plan is more appropriate to address the long term sustainability of achievements made.

7.11.1 Objective Over the duration of this Plan, ensure the ongoing control of contorta pine within the Marlborough region in order to minimise adverse effects on the environment, enjoyment of the natural environment and economic wellbeing.





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Principle measures to achieve the objective 1) Collaborative Programmes

Council will support and play a leadership role in seeking to establish collaborative programmes outside of the Plan that would in turn give effect to the programme objective.








Council may:






7.11.2 Analysis of the benefits and costs for contorta pine Background Contorta (or Lodgepole) pine (Pinus contorta) was planted in the hill country of Marlborough during the era of soil conservation efforts. Over the following decades, the trees planted not only established but began to spread prolifically out onto surrounding land. Seed of contorta pine can be blown long distanced during high wind events and wilding trees can bear cones in 3-5 years beginning the cycle again.

Current situation in 2017 Contorta pine can be found where originally planted in the Branch/Leatham catchment, Wye catchment, Waihopai catchment and in the Richmond Ranges. Prolific spread has occurred surrounding the Wye Reserve and also within and on the margins of the Branch/Leatham catchment. Other smaller isolated plantings have been anecdotally noted in other locations within Marlborough.

Baseline: No RPMP In this scenario, no control of contorta pine is undertaken, and the assumption is made that the species continues to establish in new areas and no attempt is made to control original infestations.


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Control option(s): 1. Progressive Containment Programme: In which the intermediate outcome for the

programme is to contain or reduce the geographic distribution of the subject, or an organism being spread by the subject, to an area over time. This option is outlining all control requirements in detail, within the RPMP framework.

2. Sustained Control Programme: In which the intermediate outcome for the programme is to provide for ongoing control of the subject, to reduce its impacts on values and spread to other properties. This option is post collaborative management, as per the proposed programme structure.

Level of analysis for contorta pine Council has determined that a low level of analysis be undertaken for contorta pine. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.

Impacts Identify impact Quantify impact

Environmental Contorta pine grows faster and taller than low-stature indigenous vegetation. Indigenous ecosystems that are at particular risk of invasion include: tussock and other indigenous grasslands; alpine ecosystems; subalpine, dryland and other scrub and shrublands; wetlands; turf communities and coastal margins, cliffs and bluffs. Once they have invaded, trees can shade out many native plant communities and can also change soil characteristics11.

An exercise to assess vulnerability of invasion by wilding conifers was conducted as part of the National Wilding Conifer Programme. This took into account the nature of land cover coupled with an assessment of how vulnerable that land cover is to invasion. For Marlborough, a total of 433,259 hectares was assessed as being either high or very high in terms of vulnerability to invasion. This is approximately 39% of the land area of the Marlborough region.

Landscape Values Impacts on landscape values can be dependent on perception and preference. However, through RMA processes and district plans, areas can be designated Outstanding Natural Landscapes (ONL) or Visual Amenity Landscapes (VAL). There is concern that spreading wilding conifers could so alter the basic characteristics of the local landscapes so that they become forest dominated.

Significant areas of the Marlborough region have been identified as being areas of Outstanding Natural Landscape value. This includes both areas in the Marlborough Sounds and inland Marlborough that both have impacts from changes to the landscape due to wilding conifer invasion.

Water Quantity Where there are significant changes to land cover within a catchment, such as a domination of contorta pine, surfaces water flows can be negatively affected. This is more pronounced in dry South Island catchments.

Data from studies on surface water yield has shown there pasture dominated catchments were replaced by radiata pine forest, there was a reduction in annual surface water yields of 30-81%12,13.

11 Froude, V.A. 2011. Wilding conifers in New Zealand: Status Report. Prepared for the Ministry of Agriculture and Forestry.

12 Duncan MJ 1996. A methodology for identification of areas vulnerable to flow reductions because of afforestation. NIWA Christchurch Consultancy Report No CRC60512. Cited in Environment Canterbury Regional Council 2011. Christchurch. 13 Environment Canterbury Regional Council 2011. Canterbury Natural Resources Regional Plan.Chapter 5: water quantity. http://ecan.govt.nz/publications/Plans/nrrp-chapter-5-cover- main-text-operative-110611.pdf , Environment Canterbury RegionalCouncil. 214 p.


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Economic Once wilding contorta pine spreads onto extensive or marginal farmland, active control required may be difficult for the land owner/occupier to justify financially given the marginal worth of the land for grazing. This can result in a compounding reduction on land area available for extensive grazing.

There are three categories of land cover within the Land Cover Database (2012)14 that is associated with extensive grazing. These are low producing grassland, depleted grassland and tall tussock grassland. These three land cover classes total 246,583 hectares in the Marlborough region.








Regional community



14 https://lris.scinfo.org.nz/layer/412/SourceLCDB v4.0 Landcare Research Creative Commons Attrribution 3.0 New Zealand. Accessed 7 August 2017.

https://lris.scinfo.org.nz/layer/412/SourceLCDB%20v4.0


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Benefit Option

No RPMP Progressive Containment Sustained Control The prevention of contorta pine re-establishing and the resulting impact of that on environmental values.

No programme cost The benefit under a Progressive Containment Programme will increase to a point where the organism is within designated ‘containment areas’ then remains constant throughout the life of the Plan.


The prevention of contorta pine re-establishing and the resulting impact of that on landscape values.

The prevention of contorta pine re-establishing and the resulting impact of that on catchment water yields.

The prevention of contorta pine re-establishing and the resulting impact of that on production values of pastoral land.


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No RPMP Progressive Containment Sustained Control

Council costs • Surveillance • Administration • Education/awareness

-

$20,000 $500

Council costs • Service delivery

$100,000+ $500

Land occupier costs - $400,000+ $015

Total per annum - $520,000+ $500


Low, but increases






15 The main mechanism of this proposed programme is acknowledging the work of Collaborative Wilding Conifer Programmes. Given there are not any programmes currently in place or near completion, the cost on land occupiers under this RPMP programme has been assessed as being nil. Council and land occupiers may be actively involved in one or more of the programmes outside of the RPMP. Details and the status of these programmes will be outlined within the Operational Plan and reported upon annually. This is because the Operational Plan will cover all Council biosecurity activities, both RPMP and non-RPMP.


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Level of Risk

Option


N/A High Low/Moderate

Reason The effective management of contorta pine to a progressive containment objective within a RPMP programme would set a level of expectation that effective management was to occur. As a result, there is a real risk of political and/or public concern over cost that would adversely affect the implementation of the programme.

Given the Sustained Control Programme would only commence in behind other collaborative initiatives, the starting point will be very low infestation levels. As such, the risk of not keeping areas subject of the programme under sustained control will be low.


Most preferred option Sustained Control Programme (with the active management to occur outside of the RPMP under Collaborative Wilding Conifer Programmes, detailed within the Operational Plan).


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7.12 Corsican pine (Pinus nigra) Why is it a threat? Corsican pine can have significant impacts on native ecosystems, particularly those low in stature, such as tussock and indigenous grasslands, alpine ecosystems and subalpine scrub. Corsican pine grows faster and taller than low-stature vegetation so can easily out-compete these species. Soil and soil fauna are also altered when wilding conifers replace native ecosystems.

Corsican pine can also adversely affect amenity and landscape values. These landscapes are important for tourism and large scale landscape changes can impact on the value gained from tourism in Marlborough.

In areas where there is long term, seasonal soil moisture deficits, dense wilding conifer stands can contribute to reductions in surface water flows, potentially impacting on water availability and associated aquatic ecosystems.


In areas of extensive pastoral farming, Corsican pine infestations adversely impact economic wellbeing by reducing available grazing and limited the options for future land use.

Reasons for proposing a Plan In Marlborough, it is recognised the first up task of managing Corsican pine to sustainable levels is one best carried out through large scale collaborative programmes outside of the Plan. However, to ensure the achievements gained by investing in management (by a number of parties), a programme within a Plan can ensure the gains made are sustainable in the long term. As such, the proposed programme reflects this.

Why the Plan is more appropriate than relying on voluntary actions In essence, the previously mentioned collaborative management projects are voluntary actions. Interested parties, including the Council, the Department of Conservation, the Ministry for Primary Industries (MPI), Land Information New Zealand, the community at large and other organisations recognise the importance of managing Corsican pine. This culminated in the development of the New Zealand Wilding Conifer Management Strategy (2015) then subsequent Crown Funding administered by MPI to invest in the issue (the National Wilding Conifer Management Programme). Prior to this, local trusts, such as the Marlborough Sounds Restoration Trust and South Marlborough Landscape Restoration Trust, established through a community desire to take action for community good.

All of these aspects to Corsican pine management is occurring under the banner of voluntary action.

However, management of Corsican pine is a long game. Under all of the scenarios of intervention, there is a concern that up-front investment could be put at risk by a lack of voluntary actions being undertaken at an individual land occupier level. As such, it is proposed that this Plan acknowledges the success of voluntary action in one respect (the broad collaborative management approaches), but the Plan is more appropriate to address the long term sustainability of achievements made.

7.12.1 Objective Over the duration of this Plan, ensure the ongoing control of Corsican pine within the Marlborough region in order to minimise adverse effects on the environment, enjoyment of the natural environment and economic wellbeing.





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Council may:






7.12.2 Analysis of the benefits and costs for Corsican pine Background A less prevalent conifer species in Marlborough, Corsican pine (Pinus nigra) has demonstrated invasive characteristics in many New Zealand, and where established, specific locations in Marlborough. This species has been recognised as having moderate-high spreading vigour in the 2012 wilding spread risk calculator developed for the National Environmental Standard for Plantation Forestry.

Current situation in 2017 Corsican pine can be found where originally planted on the Raglan Range and at selected locations on Molesworth Station. Whilst not in Marlborough, in the southern areas of Molesworth Station near Jacks and Jollies Passes, Corsican pine has shown to be a prolific spreading species contributing to the proliferation of wilding trees in the Maukuratawhai area.

Baseline: No RPMP In this scenario, no control of Corsican pine is undertaken, and the assumption is made that the species continues to establish in new areas and no attempt is made to control original infestations.

Control option(s): 1. Progressive Containment Programme: In which the intermediate outcome for the programme

is to contain or reduce the geographic distribution of the subject, or an organism being spread by the subject, to an area over time. This option is outlining all control requirements in detail, within the RPMP framework.



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Level of analysis for Corsican pine Council has determined that a low level of analysis be undertaken for Corsican pine. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.


Environmental Corsican pine grows faster and taller than low-stature indigenous vegetation. Indigenous ecosystems that are at particular risk of invasion include: tussock and other indigenous grasslands; alpine ecosystems; subalpine, dryland and other scrub and shrublands; wetlands; turf communities and coastal margins, cliffs and bluffs. Once they have invaded, trees can shade out many native plant communities and can also change soil characteristics16.




Water Quantity Where there are significant changes to land cover within a catchment, such as a domination of Corsican pine, surfaces water flows can be negatively affected. This is more pronounced in dry South Island catchments.





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Economic Once wilding Corsican pine spreads onto extensive or marginal farmland, active control required may be difficult for the land owner/occupier to justify financially given the marginal worth of the land for grazing. This can result in a compounding reduction on land area available for extensive grazing.









Regional community






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Benefit Option


The prevention of Corsican pine re-establishing and the resulting impact of that on environmental values.



The prevention of Corsican pine re-establishing and the resulting impact of that on landscape values.

The prevention of Corsican pine re-establishing and the resulting impact of that on catchment water yields.

The prevention of Corsican pine re-establishing and the resulting impact of that on production values of pastoral land.

Corsican pine is still utilised on occasions as a timber production species

The benefit would continue to be realised.

No benefit to be realised. No benefit to be realised.


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No RPMP

Progressive Containment

Sustained Control


-

$20,000 $0


$100,000+ $500




Low, but increases






20 The main mechanism of this proposed programme is acknowledging the work of Collaborative Wilding Conifer Programmes. Given there are not any programmes near completion, the cost on land occupiers under this RPMP programme has been assessed as being nil. Council and land occupiers may be actively involved in one or more of the programmes outside of the RPMP. Details and the status of these programmes will be outlined within the Operational Plan and reported upon annually. This is because the Operational Plan will cover all Council biosecurity activities, both RPMP and non-RPMP.


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Level of Risk

Option



Reason The effective management of Corsican pine to a progressive containment objective within a RPMP programme would set a level of expectation that effective management was to occur. As a result, there is a real risk of political and/or public concern over cost that would adversely affect the implementation of the programme.





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7.13 Cotton thistle (Onopordum acanthium) Why is it a threat? Cotton thistle is native to Europe, western and central Asia. It arrived in New Zealand during the 1880s. Cotton thistle is an erect annual or biennial thistle growing up to 2 metres tall (typically 1-1.2 metres). The main dispersal method is by seeds attaching to animal coats. Seeds hairs are not adequate for wind dispersal, but can be transported by strong winds. It invades and colonises pasture. If left uncontrolled it will form dense infestations and displace preferred pasture species and impede access to stock. It is a competitive weed in improved pasture and favours soils with high levels of nitrogen. Cotton thistle is prevalent in Canterbury and Otago. Cotton thistle has the potential to be a significant farmland weed throughout Marlborough.

Reasons for proposing a Plan Infestations in Marlborough are limited to nine sites, with only three of which active infestations. Unfortunately, like many weed species, complete removal is a long and arduous task with some of the three remaining sites harbouring a large number of seedlings each year.

There is a significant net benefit to the control of cotton thistle based on the potential for damage to Marlborough’s pastoral farming economy and the potential to displace Marlborough’s native species.


7.13.1 Objective Over the duration of the Plan, control cotton thistle (Onopordum acanthium) in the Marlborough district to less than or equal to baseline levels* to minimise adverse effects on economic wellbeing, the environment and enjoyment of the natural environment.

*A baseline level assessment will be made either prior to or immediately after the Plan commences.






a) Delivering a service to manage cotton thistle in liaison with the occupier.









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Council may:






7.13.2 Rules Rule 7.13.2.1 Occupiers are required to notify Council of any new infestation of cotton thistle (Onopordum acanthium) on land that they occupy within 5 working days of the initial observation.











7.13.3 Analysis of the benefits and costs for cotton thistle Background In the summer of 2004, a land occupier from the Awatere Valley brought a thistle specimen into Council that he had not seen before and was concerned about its spread on his property. Council staff sent the specimen to Landcare Research who identified the plant as cotton thistle (Onopordum acanthium). At around the same time, a Council staff member found a patch of this thistle growing along a stopbank on the Wairau Bar Road.

Research into cotton thistle at the time concluded the following:

• It is a native of the Eastern Mediterranean. In New Zealand, small infestations exist in the Hawkes Bay, South Canterbury and Otago.

• It is a vigorous biennial which can invade and colonise pastures. This plant can tolerate droughts, spread in drier areas and is resistant to commonly used hormone sprays.


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• Biosecurity Officers in Canterbury and Otago with infestations in their region advised that they are controlling this thistle because they perceive it to be a threat. If left uncontrolled, it does appear to form dense infestations and spread quickly.

• Hawkes Bay Regional Council has it classified as a ‘Total Control’ plant in their Regional Pest Management Strategy. All plants are destroyed before they produce seed.

Following this research, advertisements were placed into local newspapers to encourage public sightings. A number of calls were received from the public and inspections were carried out by Council staff. No new cotton thistle infestations were found.

Following this public campaign, Council staff undertook control work at the site on the Wairau Bar Road. A total of 260 plants were grubbed and all of their seed heads were removed.

Council staff then spent two and a half days carrying out surveillance work in the Awatere Valley, to determine the extent of the cotton thistle infestation. The land occupier has been working with Council since 2005 to control that infestation.

Cotton thistle continued to be included in the Regional Pest Management Strategy for Marlborough2102 as a surveillance pest plant

Current situation in 2017There remain only two areas with infestations of cotton thistle in Marlborough - Mt Gladstone and Wairau Bar Road. After some ongoing promotional work, individual plants were reported and removed from urban gardens where they were growing as an ornamental species.

The number of plants being found at the two active infestations peaked in 2009 but in recent years, numbers have been falling. The landholder at Mt Gladstone has been undertaking control work butthis information has not been collected for inclusion with Council’s dataset.

What has been shown since surveillance and control work commenced in 2005, is that keeping this species under sustained management is feasible.

Figure 10: The trend in infestation levels of cotton thistle in Marlborough

** Note: The cotton thistle dataset does not include a complete dataset from the Mt Gladstone infestation.


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Options to respond to cotton thistle Baseline: No RPMP In this scenario no management agency control of cotton thistle is undertaken, with some landholder-driven control likely at the Mt Gladstone infestation. The plant is likely to spread progressively, be it slower from Mt Gladstone throughout the region.




Level of analysis for cotton thistle Council has determined that a low level of analysis be undertaken for cotton thistle. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.

Impacts Cotton thistle is native to Europe, western and central Asia. It arrived in New Zealand during the 1880s. Cotton thistle is an erect annual or biennial thistle growing up to 2 metres tall (typically 1-1.2 metres). The main dispersal method is by seeds attaching to animal coats. Seeds hairs are not adequate for wind dispersal, but can be transported by strong winds. It invades and colonises pasture.


Pastoral farming. If left uncontrolled it will form dense infestations and displace preferred pasture species and impede access to stock. It is a competitive weed in improved pasture and favours soils with high levels of nitrogen. Cotton thistle has the potential to be a significant farmland weed throughout Marlborough.

481,700 hectares of land at risk.








Regional community




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Benefit Option


The prevention of cotton thistle building in density or infesting new areas and the resulting impact of that on pastoral productivity.




Programme Costs

Option


GST)


GST)


GST)


- $80,000+ $4,800

Land occupier costs -

Total - $80,000+ $4,800


over time






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Risk that each option will not achieve Objective 6(2)(g) The supporting information document to this Proposal contains information to support this analysis.

Level of Risk

Option


N/A High Low

Reason The level of risk of not achieving an eradication objective, within 10 years or even at a longer time scale, is very high.

There is a lower level of risk that Council will be able to maintain a very low density of cotton thistle in Marlborough.




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7.14 Eel grass (Vallisneria australis) Why is it a threat? Eel grass is a submerged, aquatic, perennial herb that originates from Europe, Africa, Asia and Australia. It is a potential competitor with native wetland and aquatic species. It will block drains and impede water flows. It spreads by rhizome fragments. Spread is often aided by humans who may have this previously popular aquarium plant at home then dispose of it into waterways.

Reasons for proposing a Plan (individually) Infestations in Marlborough are only known at two sites - Waterlea Creek and Ōpaoa Loop. This species of aquatic plant has the potential to rapidly form dense beds of vegetation. Once detected, there has been ongoing intensive management that has held the infestations to low levels. There is the opportunity to continue this management into the future through a structured programme within a Plan.

Why the Plan is more appropriate than relying on voluntary actions With so few known sites, the management of this species needs to be both strategic and intensive. Because of this, it is more appropriate to be managed through a structured programme of delivery enabled by a Plan rather than relying on voluntary actions. With eel grass being an aquatic species, there is also no default occupier that may be affected and take voluntary action which can be the case in terrestrial environments.

7.14.1 Objective Over the duration of the Plan, control eel grass (Vallisneria australis) in the Marlborough district to less than or equal to 2016 levels to minimise adverse effects on the environment and enjoyment of the natural environment.






a) Delivering a service to manage eel grass.





a) Land owners and/or occupiers or other persons may be required to act where rules or statutory obligations dictate:

i) The presence of pests is to be reported.

ii) Pests are not to be spread (propagated, sold or distributed).


Council may:




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7.14.2 Rules Rule 7.14.2.1 Occupiers are required to notify Council of any new infestation of eel grass (Vallisneria australis) on any place that they occupy within 5 working days of the initial observation.



Explanation of the rule: The purpose of this rule is for occupiers to assist Council with surveillance. Requiring occupiers to notify Council of new sites and plants in a place they occupy, in addition to Council’s own surveillance will assist Council in achieving the objective of the programme. New infestations will be able to be controlled and incorporated into the programme.








7.14.3 Analysis of the benefits and costs for eel grass Background Eel grass was discovered growing in the Ōpaoa Loop by Council’s aquatic weed spraying contractor in 2000. It is likely it originated from the dumping of unwanted aquarium plants.

An impact and economic analysis of eel grass confirmed its inclusion in in the Regional Pest Management Strategy for Marlborough 2001 as a Total Control pest plant.

In 2001, Council staff and a contractor hand pulled all known infestations and all plants were bagged and disposed of by deep burial at the landfill. In total, 21 tonnes of eel grass was removed during the initial operation.

A new infestation of eel grass was reported in Waterlea Creek by a member of the public in 2003. Another single plant was discovered and removed further downstream in the Ōpaoa River (near the Taylor confluence). This was recorded as a third site but no evidence of the plants returning at this third site has been recorded.

Since the discovery of the Ōpaoa Loop and Waterlea Creek infestations, Council staff and/or contractors have attempted to remove all plant material from the waterway by hand removal. This can be challenging with poor water clarity common in the Ōpaoa Loop. Active surveillance of any historical locations or other un-infested sections of waterway is also ongoing.

Eel grass has continued to be a Total Control pest plant in both the 2007 and 2012 Regional Pest Management Strategy for Marlborough.


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Current situation in 2017There remain two infestations of eel grass in Marlborough; the Ōpaoa River Loop and Waterlea Creek.Each year in February/March, eel grass control is carried out at all known sites when the weather is at its hottest and the water levels are at their lowest. Divers are contracted to remove any plants and to hand pull from boats. Divers only find a few plants of eel grass in the Ōpaoa Loop each year. The visibility in the Ōpaoa Loop is severely affected by any rainfall in the Wairau or Waihopai River. Control operations cannot be attempted unless there has been a long spell with no rain. At the same time surveillance work is undertaken in Waterlea Creek.

Figure 11: The trend in infestation levels of eel grass in Marlborough

Options to respond to eel grassBaseline: No RPMPIn this scenario no control of eel grass is undertaken, and the assumption is made that the plant becomes well-established and progresses toward full naturalisation in all susceptible areas in the long term.




Level of analysis for eel grassCouncil has determined that a low level of analysis be undertaken for eel grass. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.

ImpactsEel grass is a submerged, aquatic, perennial herb that originates from Europe, Africa, Asia and Australia. It is a potential competitor with native wetland and aquatic species. It will block drains and impede water flows. It spreads by rhizome fragments. Spread is often aided by humans who throw this previously popular aquarium plant into waterways.


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Recreation values Smothers native aquatic vegetation in waterways and impedes recreational activities and water flow.

Any freshwater lakes, streams, drains, rivers and ponds on their property and the people that utilise these for recreational purposes

Conservation values Threaten values held within wetlands in the district. Native wetland and aquatic species.

Protection of 2,900 hectares of inland waterways in the district.

Hydrology Block drains and impede water flows causing flooding.

There are 160 kilometres of Council maintained scheduled watercourses and drains. As part of this network, Council maintains 24 Rural flood protection and drainage pumping stations and 320 flood gated gravity outlets to the main river systems.








Regional community




Benefit Option


The prevention of eel grass building in density and infesting new areas and the resulting impact of that on environmental values.




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Programme Costs

Option


GST)


GST)


GST)


- $20,000+ $4,500


Total - $20,000+ $4,500


over time






Level of Risk

Option


N/A High Low

Reason The level of risk of not achieving an eradication objective, within 10 years or even at a longer time scale, is very high. Given the biological nature of eel grass and the poor water clarity the effective removal of all plants parts is very difficult, near to impossible. It is very unlikely that this species will be eradicated.

There is a lower level of risk that Council will be able to maintain a very low density of eel grass in Marlborough


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7.15 European larch (Larix decidua) Definition Excludes sterile hybrids of European larch (Larix decidua)

Why is it a threat? European larch can have significant impacts on native ecosystems, particularly those low in stature, such as tussock and indigenous grasslands, alpine ecosystems and subalpine scrub. European larch grow faster and taller than low-stature vegetation so can easily out-compete these species. Soil and soil fauna are also altered when wilding conifers replace native ecosystems.

European larch can also adversely affect amenity and landscape values. These landscapes are important for tourism and large scale landscape changes can impact on the value gained from tourism in Marlborough.

In areas where there is long term, seasonal soil moisture deficits, dense European larch stands can contribute to reductions in surface water flows, potentially impacting on water availability and associated aquatic ecosystems.


In areas of extensive pastoral farming, European larch infestations adversely impact economic wellbeing by reducing available grazing and limited the options for future land use.

Reasons for proposing a Plan In Marlborough, it is recognised the first up task of managing European larch to sustainable levels is one best carried out through large scale collaborative programmes outside of the Plan. However, to ensure the achievements gained by investing in management (by a number of parties), a programme within a Plan can ensure the gains made are sustainable in the long term. As such, the proposed programme reflects this.

Why the Plan is more appropriate than relying on voluntary actions In essence, the previously mentioned collaborative management projects are voluntary actions. Interested parties, including Council, the Department of Conservation, the Ministry for Primary Industries (MPI), Land Information New Zealand, the community at large and other organisations recognise the importance of managing European larch. This culminated in the development of the New Zealand Wilding Conifer Management Strategy (2015) then subsequent Crown Funding administered by MPI to invest in the issue (the National Wilding Conifer Management Programme). Prior to this, local trusts, such as the Marlborough Sounds Restoration Trust and South Marlborough Landscape Restoration Trust, established through a community desire to take action for community good.

All of these aspects to European larch management is occurring under the banner of voluntary action.

However, management of European larch is a long game. Under all of the scenarios of intervention, there is a concern that up-front investment could be put at risk by a lack of voluntary actions being undertaken at an individual land occupier level. As such, it is proposed that this Plan acknowledges the success of voluntary action in one respect (the broad collaborative management approaches), but the Plan is more appropriate to address the long term sustainability of achievements made.

7.15.1 Objective Over the duration of this Plan, ensure the ongoing control of European larch within the Marlborough region in order to minimise adverse effects on the environment, enjoyment of the natural environment and economic wellbeing.


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Council may:






7.15.2 Analysis of the benefits and costs for European larch Background European larch was planted in the hill country of the South Island during the era of soil conservation efforts by Catchment Boards or through former Forest Service trials. The seed of European larch is particularly light in mass, so can be readily blown some distance to give rise to wilding spread21

Current situation in 2017 In Marlborough, European larch has been planted at numerous locations in the past, such as the Wye Reserve, the Branch/Leatham catchment and parts of southern Molesworth. Evidence of spread has been found as part of management programmes occurring within or near these areas of Marlborough.

Baseline: No RPMP In this scenario no control of European larch is undertaken, and the assumption is made that the plant becomes well-established and progresses toward full naturalisation in all susceptible areas in the long term.

21 Ledgard, N. 2007. Everyone likes larches. Tree grower article in New Zealand Tree Grower. November 2007.


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Control option(s): 1. Progressive Containment Programme: In which the intermediate outcome for the programme



Level of analysis for European larch Council has determined that a low level of analysis be undertaken for European larch. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.


Environmental European larch grows faster and taller than low-stature indigenous vegetation. Indigenous ecosystems that are at particular risk of invasion include: tussock and other indigenous grasslands; alpine ecosystems; subalpine, dryland and other scrub and shrublands; wetlands; turf communities and coastal margins, cliffs and bluffs. Once they have invaded, trees can shade out many native plant communities and can also change soil characteristics22.




Water Quantity Where there are significant changes to land cover within a catchment, such as a domination of European larch, surfaces water flows can be negatively affected. This is more pronounced in dry South Island catchments.





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Economic Once wilding European larch spreads onto extensive or marginal farmland, active control required may be difficult for the land owner/occupier to justify financially given the marginal worth of the land for grazing. This can result in a compounding reduction on land area available for extensive grazing.









Regional community




Benefit Option


The prevention of European larch re-establishing and the resulting impact of that on environmental values.






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The prevention of European larch re-establishing and the resulting impact of that on landscape values.

The prevention of European larch re-establishing and the resulting impact of that on catchment water yields.

The prevention of European larch re-establishing and the resulting impact of that on production values of pastoral land.



No RPMP


Sustained Control


-

$20,000 $0


$100,000+




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Low, but increases







Level of Risk

Option



Reason The effective management of European larch to a progressive containment objective within a RPMP programme would set a level of expectation that effective management was to occur. As a result, there is a real risk of political and/or public concern over cost that would adversely affect the implementation of the programme.





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7.16 Evergreen buckthorn (Rhamnus alaternus) Why is it a threat? Evergreen buckthorn is an evergreen shrub that originates from the Mediterranean region. It will grow in scrub around forest margins, in plantations and on coastal cliffs. It is spread by birds as its seed is contained in a fleshy fruit. It displaces native species and hinders regeneration of forest remnants.

Reasons for proposing a Plan Infestations in Marlborough continue to only be found in the Manaroa area of the Marlborough Sounds. Given the bird dispersed nature of this plant, plants can be found over a reasonable large geographic area within the Manaroa area. If left to become well-established, this plant can compete and thrive in the understory of regenerating forested ecosystems throughout the Marlborough Sounds.

Why the Plan is more appropriate than relying on voluntary actions With so few known sites, and confined to one geographic area, the management of this species needs to be both strategic and intensive. It is also very difficult to identify when amongst native vegetation. Therefore, voluntary actions are not considered an effective management method.

7.16.1 Objective Over the duration of the Plan, control of evergreen buckthorn (Rhamnus alaternus) in the Marlborough district to less than or equal to 2015 levels to minimise adverse effects on the environment and enjoyment of the natural environment.






a) Delivering a service in conjunction with the Department of Conservation to manage evergreen buckthorn.









Council may:





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7.16.2 Rules Rule 7.16.2.1 Occupiers are required to notify Council of any new infestation of evergreen buckthorn (Rhamnus alaternus) on land that they occupy within 5 working days of the initial observation.



Explanation of the rule: The purpose of this rule is for occupiers to assist Council with surveillance. Having occupiers notifying Council of new sites and plants on their properties, in addition to Department of Conservation surveillance, will assist Council in achieving the objective of the programme. New infestations will be able to be controlled and incorporated into the programme.








7.16.3 Analysis of the benefits and costs for evergreen buckthorn

Background Department of Conservation staff discovered an extensive infestation of evergreen buckthorn growing at Manaroa in the Marlborough Sounds while carrying out weed survey work in the area. They began annual control on this infestation with the permission of the land owners.

Evergreen buckthorn was included in the 2001 Regional Pest Management Strategy for Marlborough as a surveillance plant. In 2007, as a result of a review of the 2001 Regional Pest Management Strategy for Marlborough, evergreen buckthorn became a Total Control pest plant in the new Regional Pest Management Strategy for Marlborough.

Current situation in 2017 The original infestation of evergreen buckthorn at Manaroa has spread further than was originally anticipated, although in the same vicinity. In total, there are now seven sites that have evergreen buckthorn. Six of the seven sites are in or near Clova Bay, with a further site nearby in Crail Bay. All new infestations have been entered into the ongoing control regime. Department of Conservation staff with support from Council staff lead the control of this weed in November each year when the plant begins to fruit and is more easily seen. Seedlings are hand pulled and large plants are cut and treated with herbicide applied to the cut stump.

There are currently seven sites in Marlborough with evergreen buckthorn infestations. Each year, searches continue to be carried out in an attempt to control all plants before seed setting via fruit that can lead to further distribution by birds.


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Figure 12: The trend in infestation levels of evergreen buckthorn in Marlborough

Options to respond to Evergreen BuckthornBaseline: No RPMPIn this scenario no control of evergreen buckthorn is undertaken, and the assumption is made that the plant becomes well-established and progresses toward full naturalisation in all susceptible areas in the long term.




Level of analysis for evergreen buckthornCouncil has determined that a low level of analysis be undertaken for evergreen buckthorn. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.

ImpactsEvergreen buckthorn is an evergreen shrub that originates from the Mediterranean region. It will grow in scrub around forest margins, in plantations and on coastal cliffs. It is spread by birds as its seed is contained in a fleshy fruit. It displaces native species and hinders regeneration of forest remnants.


Conservation valuesIts ability to displace native species and hinder regeneration of forest remnants.Displaces and invades native vegetation in forest, scrub and coastal margins.

At risk habitat: 451,423 hectares


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Regional community




Benefit Option


The prevention of evergreen buckthorn building in density and infesting new areas and the resulting impact of that on environmental values.




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Costs of each option The operational aspect of the programme will not change in that an attempt will be made each year to control as much of the infestations as is possible.

Programme Costs

Option


GST)


GST)


GST)


- MDC $10,000+ DOC $50,000+

MDC $4,800 DOC $6,400


Total - $60,000+ $11,200


over time




Rationale for the allocation of costs It has been recognised that due to the location of the infestations of evergreen buckthorn in Marlborough, the Department of Conservation wishes to co-manage this species. As such, a large portion of the cost of the programme has been allocated to the Department of Conservation. This is in recognition of the Department of Conservation being a major beneficiary of this programme.



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Level of Risk

Option


N/A High Low

Reason The level of risk of not achieving an eradication objective, within 10 years or even at a longer time scale, is very high. Council and the Department of Conservation acknowledge that they are unlikely to achieve zero levels in the next ten years (the life of the next Plan). This is mainly because of the difficulty in identifying evergreen buckthorn in amongst native vegetation and difficult terrain. It is believed that the infestations can be supressed to a point where further dispersal is minimised and there is no increase in population size.

There is a lower level of risk that Council and the Department of Conservation will be able to maintain a low density of evergreen buckthorn in Marlborough. This will be achieved by ongoing control at sites and with structured surveillance of all known sites and other risk areas over time.

Mitigation Options No mitigation options are assessed as being available to adjust the level of risk of options not achieving the objective.



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7.17 Giant needle grass (Austrostipa rudis) Why is it a threat? Giant needle grass is a perennial, tussock forming grass, which originates from Eastern Australia. Its general appearance is not unlike Chilean needle grass (Nassella neesiana). It will grow up to 1.3 metres high, which is twice the height of Chilean needle grass. It spreads through seed, which lacks the aggressive point and barb that Chilean needle grass has. Giant needle grass will displace desirable pasture species and forms dense infestations if left uncontrolled.

Reasons for proposing a Plan Giant needle grass appears capable of causing damage to Marlborough’s pastoral farming economy and in particular, areas of South Marlborough with much lower rainfall and moisture deficits over summer. Since first being detected in Marlborough some decades ago, there remains to be only a small number of confirmed infestations that continue to be under management. Giant needle grass fall into a strategic category of being very early in the establishment phase with strategic management now providing the greatest level of long term benefit.

Why the Plan is more appropriate than relying on voluntary actions With so few known sites, the management of this species needs to be both strategic and intensive. It can also be very difficult to identify, being a grass within the Austrostipa genus. Therefore, voluntary actions are not considered an effective management method.

7.17.1 Objective Over the duration of the Plan, control giant needle grass (Austrostipa rudis) in the Marlborough district to less than or equal to 2014 levels to minimise adverse effects on economic wellbeing.






a) Delivering a service to control giant needle grass in liaison with the occupier.









Council may:




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7.17.2 Rules Rule 7.17.2 Occupiers are required to notify Council of any new infestation of giant needle grass (Austrostipa rudis) on land that they occupy within 5 working days of the initial observation.











7.17.3 Analysis of the benefits and costs for giant needle grass

Background Giant needle grass was initially found by a weed spraying contractor on a property near the Wairau Valley. It was then found by a Council staff member on the roadside at Shingly Creek in the upper Wairau Valley in 2000.

An impact and economic analysis in 2001 confirmed its inclusion in the Regional Pest Management Strategy for Marlborough 2001 as a total control pest plant.

Two of the active sites are on pine plantations. In 2009/2010 a huge number of plants germinated after a forestry block was harvested.

Since its inclusion in the Regional Pest Management Strategy for Marlborough it has been controlled annually using herbicides containing glyphosate. In 2012/2013 the numbers of plants controlled reduced significantly as a result of using residual herbicides.

Giant needle grass is a Total Control pest plant in the Regional Pest Management Strategy for Marlborough 2012.


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Current situation in 2017Giant needle grass has been found in two separate localities in Marlborough. These are near the Wash Bridge in the Upper Wairau Valley (seven sites) and in Dashwood Pass (one site identified in 2012/2013).

Only three sites are currently active with all three in the Upper Wairau Valley.

Figure 13: The trend in infestation levels of giant needle grass in Marlborough

Options to respond to giant needle grassBaseline: No RPMPIn this scenario no control of giant needle grass is undertaken, and the assumption is made that the plant becomes well-established and progresses toward full naturalisation in all susceptible areas in the long term.




Level of analysis for giant needle grassCouncil has determined that a low level of analysis be undertaken for giant needle grass. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.

ImpactsGiant needle grass is a perennial, tussock forming grass, which originates from Eastern Australia. Its general appearance is not unlike Chilean needle grass (Nassella neesiana). It will grow up to 1.3 metres high, which is twice the height of Chilean needle grass. It spreads through seed, which lacks the aggressive point and barb that Chilean needle grass has. Giant needle grass will displace desirable pasture species and forms dense infestations if left uncontrolled.


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Control of giant needle grass will prevent damage to 330,000 hectares of pastoral habitat in Marlborough. It is estimated that giant needle grass will infest pastoral and tussock land covers, including up to 10% of hill country land uses (LUC Classes IV and V ), and 30% of high country land (Class VI). Modelling of this scenario assumed spread characteristics of between 10 and 200 metres for mature plants, and between 30 and 60 years to reach its maximum density at a site in an uncontrolled situation.








Regional community




Benefit Option


The prevention of giant needle grass infesting new areas and the resulting impact of that on pastoral production values.

No programme cost The values protected by the control of giant needle grass are largely pastoral production values. Control of giant needle grass will prevent damage to 330,000 hectares of pastoral and tussock habitat. The benefit under an Eradication Programme will increase to an end point when the objective is able to be achieved.

The values protected by the control of giant needle grass are largely pastoral production values. Control of giant needle grass will prevent damage to 330,000 hectares of pastoral and tussock habitat. The benefit under a Sustained Control Programme will remain constant throughout the life of the Plan, with no end point.


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Programme Costs

Option


GST)


Sustained Control Annual cost (excl GST)


- $20,000+ $7,200


Total - $20,000+ $7,200








Level of Risk

Option


N/A High Low

Reason Giant needle grass is very limited in distribution and the number of plants being controlled is low. However, invasive grasses are notoriously difficult to manage and some of the infestations are in or near forestry operations.

There is a lower level of risk that Council will be able to maintain a low density of giant needle grass in Marlborough. This will be achieved by ongoing control at sites and with structured surveillance of all known sites and other risk areas over time.


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7.18 Gorse (Ulex europaeus) Why is it a threat? Gorse is an erect, spiky, perennial shrub that will grow up to 4 metres high and originates from Eurasia. It will form dense patches if left uncontrolled. It seeds from explosive fruits, which are resistant to fire. Gorse will displace preferred pasture species and dense patches impede stock access. It will grow on pastoral country, in hedgerows, waste places and plantations from the coast to high altitudes. Its vigorous growth habit will displace native herbaceous species. The presence of gorse will greatly reduce the economic viability of a farming unit.

Reasons for proposing a Plan Gorse has in the past been classified as a noxious plant then subsequently as a pest under early Regional Pest Management Strategies. In Marlborough, there are still large areas of the district with none or very little gorse infestation. These areas are the primary focus in the new Plan.

There is a significant net benefit to the control of gorse based on the potential for damage to Marlborough’s pastoral farming economy.

Why the Plan is more appropriate than relying on voluntary actions If control was left to the voluntary actions of occupiers and no control was undertaken, there is a real risk that adequate management would not occur. The inclusion of a programme for gorse in the Regional Pest Management Plan will ensure this pest plant is kept under control with the values of the catchments identified protected.

7.18.1 Objectives 7.18.1 Over the duration of the Plan, control gorse (Ulex europaeus) in the Upper Awatere

Gorse Control Zone and the Upper Wairau and Waima/Ure Broom and Gorse Control Zones to minimise adverse effects on economic wellbeing, the environment and enjoyment of the natural environment.

7.18.2 Over the duration of the Plan, control gorse (Ulex europaeus) across the remainder of the district, in situations where the presence of gorse on boundaries threatens adjoining land clear of or being managed for gorse, to minimise adverse effects on economic wellbeing.














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Council may:






7.18.2 Rules Rule 7.18.2.1 Occupiers within the Upper Awatere Gorse Control Zone and Upper Wairau or Waima/Ure Broom and Gorse Control zones (see Maps 5), shall destroy all gorse (Ulex europaeus) plants, on land that they occupy, each year before they produce seed, unless a management plan approved by Council is in place.


Rule 7.18.2.2 No person shall transport any risk goods into the Upper Awatere Gorse Control Zone or Upper Wairau or Waima/Ure Broom and Gorse Control zones that may contain gorse (Ulex europaeus).


Rule 7.18.2.3 (Good Neighbour Rule) Occupiers shall destroy all gorse (Ulex europaeus) plants, on land they occupy, within 10 metres of their property boundary each year before they produce seed, where:

a) the gorse occurs over a stretch of boundary greater than 50 metres in length, and;

b) the adjoining land is clear of, or under management for gorse and the land is being used for agricultural production purposes.


Rule 7.18.2.4 Occupiers are required to notify Council of any new infestation of gorse (Ulex europaeus) on land that they occupy within the Upper Awatere, Upper Wairau or Waima/Ure Gorse Control Zones within 5 working days of the initial observation.


Note: Current distribution data held by Council is able to be viewed online via Council’s Smart Maps service.


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Explanation of the rules: The purpose of Rule 7.18.2.1 is in accordance with section 73(5)(h) in that all occupiers within the Upper Awatere, Upper Wairau and Waima/Ure Gorse Control Zones are being required to take specified actions to prevent the pest establishing further on that land.

The purpose of Rule 7.18.2 is in accordance with section 73(5)(e) in that activities that may be at risk of introducing gorse in to the Control Zones are regulated as the constant re-introduction of gorse into the Control Zones via contaminated goods will affect the implementation of the Plan.

The purpose of Rule 7.18.2.3 is in accordance with section 73(5)(h) in that all occupiers of land harbouring an infestation of gorse are being required to take specified actions to prevent spread pressure onto adjoining properties where the adjoining land is clear of, or under management for gorse and the land is being used for primary production purposes.



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Map 5: Upper Awatere gorse programme

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7.18.3 Analysis of the benefits and costs for gorse Background Gorse is widespread over most of Marlborough, more so north of the Wairau River. However, there are significant areas in some catchments where the level of gorse infestation is very low.

An impact and economic analysis in 2001 for gorse recommended that gorse is a ‘containment control’ plant pest throughout Marlborough and a ‘containment control’ plant pest in the Upper Wairau containment area in the proposed Regional Pest Management Strategy.

A programme for gorse was included in the Regional Pest Management Strategy for Marlborough 2001 recognising an area in Marlborough that was predominantly free of gorse - that being the Upper Wairau Catchment. In the Upper Wairau Catchment, only isolated infestations of gorse existed and generally they were the result of roading and forestry operations.

During the analysis phase for the Regional Pest Management Strategy for Marlborough 2001, the Upper Awatere Catchment was analysed to also be a ‘containment control’ area. For reasons that are not documented, this never eventuated into the final Regional Pest Management Strategy for Marlborough 2001.

The same programmes were continued in the Regional Pest Management Strategy for Marlborough 2007 and also the Regional Pest Management Strategy for Marlborough 2012 (a roll-over).

Current situation in 2017 Gorse is currently a Containment Control Pest in the Regional Pest Management Strategy for Marlborough 2012. The existing programme for gorse has two components:

1. A geographical containment areas in the Upper Wairau where all gorse must be managed by landholders (with some operational exemptions),

2. A boundary-related rule whereby upon complaint, Council can enforce a 10 metre boundary setback when the scenario meets certain criteria.

Gorse remains a well-entrenched species across much of the Marlborough district. In the Upper Awatere catchment, while infestations of gorse are present at moderate levels, they are geographically isolated and under some form of management. In the Upper Wairau catchment, the level of gorse is by in large at zero levels with the exception of areas at the bottom end of the control area where gorse infestations are present. The Waima/Ure catchment is near zero-levels with respect to gorse infestation.

Options to respond to Gorse Baseline: No RPMP In this scenario no control of gorse is undertaken, and the assumption is made that the plant becomes well-established and progresses toward full naturalisation in all susceptible areas in the long term.

Control option(s): 1. A Combination using three separate programmes.

a) An Eradication Programme proposed for the Upper Awatere and Upper Wairau.

b) A new Exclusion Programme proposed for the Waima/Ure catchment. This area has been included as it is believed to have minimal gorse infestation. The community has restrictions on the gravel movement into the area and there are extremely high ecological values at threat within the catchment.




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2. A Combination using three separate programmes.

a) A Sustained Control Programme proposed for the Upper Awatere and Upper Wairau.

b) A new Exclusion Programme proposed for the Waima/Ure catchment. This area has been included as it is believed to have minimal gorse infestation. The community has restrictions on the gravel movement into the area and there are extremely high ecological values at threat within the catchment.



3. Sustained Control Programme for the whole district: In which the intermediate outcome for the programme is to provide for ongoing control of the subject, to reduce its impacts on values and spread to other properties. The various aspects of the programme can be defined via objectives, maps and rule wording.

Level of analysis for gorse Council has determined that a low level of analysis be undertaken for gorse. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached and additional information for the cost allocation analysis that has been used to support the analysis presented below.

Impacts Gorse is an erect, spiky, perennial shrub that will grow to 4 metres high and originates from Eurasia. It will form dense patches if left uncontrolled and seeds from explosive fruits, which are resistant to fire. Gorse will displace preferred pasture species and dense patches impede stock access. It will grow on pastoral country, in hedgerows, waste places and plantations from the coast to high altitudes. Its vigorous growth habit will displace native herbaceous species. The presence of gorse will greatly reduce the economic viability of a farming unit. Gorse is considered a good nursery plant for the regeneration of native forest where a suitable native seed source is available.


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Economic • Diminished pasture and livestock production. • Affects on establishing plantation forestry.

There are hundreds of thousands of hectares in Marlborough that are in pastoral production and free from gorse infestations. This can either be in landscapes where gorse-free and infested land is ‘mixed’ or contiguous gorse-free land - as in the case of the proposed zones in this proposed Plan. If land becomes infested with gorse, costs of control per hectare can range from $100 per hectare for low level infestations up to $1000 per hectare if it takes holds and forms large dense stands. Across all levels of infestation, areas infested reduce the area of land capable of pastoral production27. In plantation forests gorse can reduce the height and diameter of forest trees, increase the cost of site preparation28, and make access for pruning and thinning operations difficult and therefore more expensive. The bushes grow up with the trees, compete with them for nutrients and minerals, particularly boron and phosphorus, and therefore can cause a wide variation in the growth rates of individual trees and consequently an overall decrease in stand quality and growth rates.

Biodiversity values Gorse can rapidly invade dry and disturbed areas by suppressing and inhibiting native plant communities29. South Marlborough in particular, with dry semi-arid landscapes and associated ecosystems is susceptible to invasion from gorse. The impacts of gorse can significantly reduce native plant communities in the dry Marlborough landscapes30. Gorse has been well documented in threatening high priority conservation land by out-competing rare and endangered native plants. It has also been shown that when invading braided riverbeds, gorse destroys the open habitats required by rare endemic birds and provides cover for their introduced predators31.

27 MacCarter, L.E., Gaynor, D.L. 1980. Gorse: a subject for biological control in New Zealand. New Zealand Journal of Experimental Agriculture, 8: 321-330.

28 Sandrey, R. 1985. Biological control of gorse: an ex-ante evaluation. Agricultural Economics Research Report No. 172. Lincoln College, Canterbury, New Zealand, pp 96

29Lee, W.G., Allen, R.B., Johnson, P.N. 1986. Succession and dynamics of gorse (Ulex europaeus L.) communities in the Dunedin Ecological District, South Island, New Zealand. New Zealand Journal of Botany, 24: 279-292.

30 Department of Conservation, 2010. Middlehurst Pastoral Lease Conservation Resources Report. DOCDM-606881. Page 15.

31 Owen, S.J 1998. Department of Conservation Strategic Plan for Managing Invasive Weeds. Department of Conservation, Wellington.


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Regional community




Benefit Option


The prevention of gorse building in density or infesting new areas within the Upper Wairau, Upper Awatere and Waima/Ure Control Zones and the resulting impact of that on pastoral productivity, biodiversity and social values.

No programme cost

The benefit under a combination of programmes, that includes one with an eradication objective, programme will increase over the life of the Plan then plateau.



Providing the honey industry with an important source of early spring pollen for bees32.

The benefit would likely increase over time as further land becomes infested with gorse and increases the available pollen resources.

The benefit under a combination of programmes, that includes one with an eradication objective, programme will remain constant over the life of the Plan.



32 Sandrey, R. 1985. Biological control of gorse: an ex-ante evaluation. Agricultural Economics Research Report No. 172. Lincoln College, Canterbury, New Zealand, pp 96


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Acting as a nursery crop for native seedlings33 and the useful function in biological conservation as a pioneer transient successional species in the re-establishment of indigenous forest vegetation34 35.

The benefit would likely increase over time as further land becomes infested with gorse and increases the area available for gorse to act as a nursery crop. This benefit is somewhat different in that there is no ‘active’ use of gorse in this manner. As such, it is more accurately defined as a secondary benefit.





Programme Costs

Option


Combination (1)


Combination (2)


Sustained Control


Council costs • Inspections • Surveillance • Administration • Education/awareness

- $40,000+ $7,500 $7,500

Land occupier costs - $500,000+ $80,000 $80,000

Total - $540,000+ $87,500 $87,500



Insignificant Insignificant Insignificant

33Lee, W.G., Allen, R.B., Johnson, P.N. 1986. Succession and dynamics of gorse (Ulex europaeus L.) communities in the Dunedin Ecological District, South Island, New Zealand. New Zealand Journal of Botany, 24: 279-292.

34 Druce, A.P. 1957. Botanical survey of an experimental catchment, Taita, New Zealand. Department of Scientific and Industrial Research Bulletin, 124: 1-81.

35 Healy, A.J. 1961. The interaction of native and adventive plant species in New Zealand. Proceedings of the New Zealand Ecological Society, 8: 39-43.


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Proposed allocation of costs It is proposed that the majority of the programme costs are allocated to occupiers of land within the control zones outlined within the programme. This has been done by way of rules requiring the occupiers to manage gorse.


Rationale for the allocation of costs The allocation of costs proposed relates to the beneficiary/exacerbator grouping the gorse programme has been assessed as being within. That is, both the major benefactor and exacerbator for this programme are occupiers of Rural land.



Level of Risk

Option


N/A High High Low

Reason Due to the established nature of gorse in Marlborough, including in the proposed control zone areas, the risk of not eradicating gorse within the zones would be very high.

Due to the established nature of gorse in Marlborough, the risk of gorse becoming established in a particular zone, such as the Waima/Ure or already established but not yet known of (be it in small amounts) is very high.

Within ongoing and persistent management, as many occupiers already carry out within the control zones, there is a very low risk of not achieving a sustained control objective. In most instances, the level of control will far exceed that required to ensure the populations are not expanding, and this will be encouraged.


Most preferred option Sustained Control Programme for the whole district: In which the intermediate outcome for the programme is to provide for ongoing control of the subject, to reduce its impacts on values and spread to other properties. The various aspects of the programme can be defined via the use of objectives, maps and rule wording.


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7.19 Kangaroo grass (Themeda triandra) Why is it a threat? Kangaroo grass is a large perennial grass that originates from Africa. It is an invasive species, which will form dense patches and can exclude preferred pasture species. It is considered to be a valuable grass in the dry areas of Australia, where it is grazed following burning. Once it produces a seed head again, it becomes unpalatable to stock and must be re-burned.

In Marlborough, a burn and graze regime is not appropriate due to the proximity of forestry to the sites and the possible fire risk. The result has been the establishment of three large infestations of mature kangaroo grass that has little or no feed value. In New Zealand, Marlborough has the only substantial infestation of this pest plant with other records of smaller isolated infestations in Christchurch, Nelson and Browns Island in the Hauraki Gulf.

Reasons for proposing a Plan In Marlborough, this species is only known to occur on a total of 41 properties. Only seven of those properties are heavily infested.

Given the threat this species poses as a competitor in Marlborough’s dry pastoral systems, and the limited extent, management through a Plan can ensure future impacts can be avoided over a larger area of Marlborough.

Why the Plan is more appropriate than relying on voluntary actions With few infested properties, the management of this species needs to be both strategic and intensive. Because of this, it is more appropriate to be managed under a regulatory framework enabled by a Plan rather than relying on voluntary actions alone.

7.19.1 Objective Over the duration of the Plan, control Kangaroo grass (Themeda triandra) in the Marlborough district to less than or equal to baseline levels* to minimise adverse effects on economic wellbeing, the environment and enjoyment of the natural environment.

*A baseline assessment will be made either prior to or immediately after the Plan commences.







b) Delivering a service to manage kangaroo grass for Group 1 properties in liaison with the occupier.








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Council may:






7.19.2 Rules Rule 7.19.2.1 Occupiers shall destroy all kangaroo grass (Themeda triandra) plants, on land that they occupy before they produce seed, except in areas of land they occupy that falls within a Kangaroo Grass Containment Area (see Maps 6 - 8), which is subject to Rule 7.19.2.2.


Rule 7.19.2.2 Occupiers of land within a Kangaroo Grass Containment Area (see Maps 6 - 8) shall destroy all kangaroo grass (Themeda triandra) on land they occupy before they produce seed within 5 metres of the Containment Area boundary.


Rule 7.19.2.3 Occupiers are required to notify Council of any new infestation of kangaroo grass (Themeda triandra) on land that they occupy within 5 working days of the initial observation.


Note - Current distribution data is able to be viewed online via Council’s Smart Maps service.

Explanation of the rule: The purpose of Rule 7.19.2.1 is in accordance with section 73(5)(h) in that all occupiers without a heavy infestation are being required to take specified actions to prevent the pest establishing on that land.

The purpose of Rule 7.19.2.2 is in accordance with section 73(5)(h) in that the occupiers of land where heavy infestation occur are required to take specified actions to prevent spread pressure on the edges of the Containment Area.



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Map 6: Kangaroo grass programme - The Narrows Containment Area


135 Map 7: Kangaroo grass programme - Vernon Containment Area


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Map 8: Kangaroo grass programme - Kaka Road Containment Area


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7.19.3 Analysis of the benefits and costs for kangaroo grass Background Council staff highlighted their concerns about the spread of kangaroo grass during the review of the Regional Pest Management Strategy for Marlborough in 2000. Kangaroo grass has been a containment control pest plant in the Regional Pest Management Strategy for Marlborough since 2001. Management has been ongoing more or less in a similar manner since.

Current situation in 2017 Kangaroo grass currently infests approximately 430 hectares in Marlborough. A total of 41 properties are recorded as having an infestation of kangaroo grass

Four occupiers are responsible for controlling all plants on ‘fringe’ properties with another seven occupiers of ‘core’ properties being required to control all plants within 5 metres of adjacent property boundaries. Council inspects all these properties to determine compliance with current strategy rules. All the remaining 30 sites are small, isolated infestations where Council staff undertake surveillance and control activities.

Occupiers and Council have been controlling kangaroo grass for 14 years. The current regime was implemented to stop any further spread of this invasive grass. Council staff were concerned in 2000 that it was spreading onto infertile hill country and occupiers had no idea of what it was or how to manage it. Knowledge surrounding the management of kangaroo grass has improved significantly. Council is confident that it is being controlled adequately.

For those heavily infested properties, if lime and fertiliser is applied to kangaroo grass, palatability to stock increases. It also allows other more palatable species to push through the sward of kangaroo grass. Discussion between landholders and Council about long term management is occurring. While there has been early promise with the potential of Taskforce herbicide to offer a selective and residual herbicide for the control of kangaroo grass, more work is required to determine out how it can be used to achieve best results.

Options to respond to kangaroo grass Baseline: No RPMP In this scenario it is assumed that no control is undertaken.

Control option(s): 1. Eradication Programme: In which the intermediate outcome for the programme is to reduce the

infestation level of the subject to zero levels in an area in the short to medium term.


Level of analysis for kangaroo grass Council has determined that a medium level of analysis be undertaken for kangaroo grass. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.

Impacts Kangaroo grass is a large perennial grass that originates from Africa. It is an invasive species, which will form dense patches and can exclude preferred pasture species. It is considered to be a valuable grass in the dry areas of Australia, where it is grazed following burning. Once it produces a seed head again, it becomes unpalatable to stock and must be re-burned. In Marlborough, a burn and graze regime is not appropriate due to the proximity of forestry to the sites and the possible fire risk. The result has been the establishment of three large infestations of mature kangaroo grass that has little value.

In New Zealand, Marlborough has the only substantial infestation of this invasive species.


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Economic • Diminished pasture and livestock

production.

Control of kangaroo grass will prevent damage to 326,000 hectares of pastoral habitat. It is estimated that kangaroo grass will infest pastoral and tussock land covers, including up to 10% of hill and high country land uses (LUC Classes IV to VII).








Regional community




Benefit Option


The prevention of kangroo grass infesting new areas and the resulting impact of that on pastoral production values.

No programme cost The values protected by the control of kangroo grass are largely pastoral production values. Control of kangaroo grass will prevent damage to 326,000 hectares of pastoral land. The benefit under an Eradication Programme will increase to an end point when the objective is able to be achieved.

The values protected by the control of kangaroo grass are largely pastoral production values. Control of kangaroo grass will prevent damage to 326,000 hectares of pastoral land. The benefit under a Sustained Control Programme will remain constant throughout the life of the Plan, with no end point.


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Programme Costs

Option


GST)


GST)


GST)


- $240,000+ $29,500

Land occupier costs - $80,000+ $50,000

Total - $320,000 $79,500


over time


Analysis An analysis has been carried out using the economic impacts of kangaroo grass to pastoral systems - see Appendices 2.4, 2.5 and 2.6. A summary and sensitivity analysis can be found below in Tables 5 and 6.


In previous analyses for benefits and costs associated with regional pest management, the recommended Treasury (previously 8%, now 6%36) has been used. However, the nature of the investment with pest management programmes can be likened to that outlined by Chris Parker writing in a New Zealand Institute of Economic Research Insight37. In that paper, a social discount rate was discussed that suggests with long term impacts that matter projects (i.e. an RPMP programme), should consider using a ‘social’ discount rate of 3-3.5%.

As a result, a conservative discount rate of 4% has been used by Council in the analyses supporting the applicable proposed programmes. This is less than that recommended by Treasury but considering the long term impacts of pest management programmes, the lower discount rate is more appropriate.




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Table 5: Summary of economic analysis for kangaroo grass

Level of Risk

Options


delivery, in conjunction with occupier)

Sustained Control (Land occupier control,

Council part service delivery)


N/A High Low

Present Value/Net Present Value (PV/NPV) (4% discount rate)

$-28,029,029 $22,532,565 $25,438,105

Probability of success (risk) 100% 20% 80%

Risk adjusted PV/NPV (4%) $-28,029,029 $465,661 $19,920,609 Table 6: Sensitivity analysis

Level of Risk

Options






High Low

Risk adjusted PV/NPV (3%) - NZIER Social rate $-40,811,615 $2,419,520 $29,651,846

Risk adjusted PV/NPV (4%) $-28,029,029 $465,661 $19,920,609

Risk adjusted PV/NPV (6%) - Default Treasury rate $-13,743,482 $-1,448,871 $9,158,573


$-42,043,543 $3,191,166 $30,734,830


$-28,029,029 $465,661 $19,920,609


$-14,014,514 $-2,259,844 $9,106,387


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Proposed allocation of costs It is proposed that the majority of the programme costs are allocated to occupiers of land that have kangaroo grass infestations. This has been done by way of rules requiring the occupiers to manage kangaroo grass.




Risk that each option will not achieve the objective The supporting information document to this Proposal contains further information to support this analysis. A summary is outlined below. These risks were translated to weighing figures used as part of the economic analysis.

Level of Risk

Option


N/A High Low

Reason Effective control tools to get infestation to zero levels in the short to medium term are not currently available for kangaroo grass. While the use of current herbicide and other farming practises can reduce infestation densities, there is a high risk that getting o zero levels would not be achieved.

The control tools that are available to manage kangaroo grass are effective in keeping infestations ‘in check’. This allows for ongoing control at levels that reduce real and future impacts.




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7.20 Madeira vine (Andredera cordifolia) Why is it a threat? Madeira vine is a vigorous climber, which originates from tropical South America. It grows from an underground tuber and also has aerial tubers that grow attached to the stem. The aerial tubers can break off easily to form new plants when they come in contact with the ground. It will also grow from rhizomes. It blocks light to supporting plants by smothering them. It can become so heavy that it breaks branches of supporting plants. It is tolerant to drought and salt spray. It prefers to grow in warm coastal sites.

Reasons for proposing a Plan Madeira vine has long been recognised as a highly invasive weed in natural ecosystem with the potential to become the next smothering vine in Marlborough’s ecosystems. Localised infestations exist throughout New Zealand where it is, in most parts, under intensive management by authorities or community groups.

Infestations in Marlborough are limited to nine sites, with only three of which are active infestations. Fortunately, two of these infestations are located on urban properties where management has involved few plants in confined spaces, although using best practise methods for management opens up new challenges.

There is a significant net benefit to the control of madeira vine based on the potential to disrupt natural ecosystems and also displace Marlborough’s native species.


7.20.1 Objective Over the duration of the Plan, control madeira vine (Andredera cordifolia) in the Marlborough district to less than or equal to 2017 levels to minimise adverse effects on the environment and enjoyment of the natural environment.






a) Delivering a service in conjunction with the Department of Conservation to manage madeira vine.





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Council may:






7.20.2 Rules Rule 7.20.2.1 Occupiers are required to notify Council of any new infestation of madeira vine (Andredera cordifolia) on land that they occupy within 5 working days of the initial observation.











7.20.3 Analysis of the benefits and costs for madeira vine Background During a review of the 1996 Regional Pest Management Strategy for Marlborough, the Department of Conservation highlighted their concerns about the discovery of this invasive weed at several sites in the Marlborough Sounds. Several infestations had been found by Department of Conservation staff carrying out a weed survey in the Sounds. Council staff worked with Department of Conservation staff carrying out parts of this survey work.


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Madeira vine became a Total Control pest plant in Regional Pest Management Strategy for Marlborough in 2001. All known sites of madeira vine fell under a control regime managed by the Department of Conservation and run in association with Council. All sites were visited and control was undertaken annually in November. Tubers were removed from the vines and bagged for destruction. The vines were then cut and the stumps treated with herbicide gel.

The number of plants controlled had a spike in 2007/2008 with the discovery of a new site. Since then, the number of plants controlled has been declining. Two new infestations have been discovered in the last two years. Both were discovered in urban Blenheim and are being managed by Council. Any plants found are removed by hand including the tubers from the ground in March/April each year.

This species has the potential to get to an Old Man’s Beard scenario in Marlborough if left unchecked.

Current situation in 2017A total of eight sites remain under management in Marlborough. For one of these sites, Madeira Vine is believed to have been eradicated so falls under a longer term surveillance programme. The remaining sites are intensively managed by either the Department of Conservation and/or Council.

The biological characteristics of the plant make complete removal/eradication very difficult. Despite an intense effort over the past 14 years, some of the original sites are still under management. There has also been the discovery of small new sites in recent years that are linked to previous gardening activities.It is believed that madeira vine infestations as a whole can be suppressed to a point where further dispersal is minimised and no increase in population size will be seen.

Figure 14: The trend in infestation levels of madeira vine in Marlborough

Options to respond to madeira vineBaseline: No RPMPIn this scenario no control of madeira vine is undertaken, and the assumption is made that the plant becomes well-established and progresses toward full naturalisation in all susceptible areas in the long term.


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Level of analysis for madeira vine Council has determined that a low level of analysis be undertaken for madeira vine. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.

Impacts Madeira vine is a vigorous climber, which originates from tropical South America. It grows from an underground tuber and also has aerial tubers that grow attached to the stem. The aerial tubers can break off easily to form new plants when they come in contact with the ground. It will also grow from rhizomes. It blocks light to supporting plants by smothering them. It can become so heavy that it breaks branches of supporting plants. It is tolerant to drought and salt spray. It prefers to grow in warm coastal sites.


Conservation values Smothers native vegetation.

Spread and occupy up to 50 % of 5000 hectares of coastal forest edge and forest habitats in Marlborough.








Regional community




Benefit Option


The prevention of madeira vine infesting new areas and the resulting impact of that on environmental values.




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Programme Costs

Option


GST)


GST)


GST)


- MDC $20,000+ DOC $10,000+

MDC $2,650 DOC $500


Total - $30,000+ $3,150


over time





Risk that each option will not achieve Objective 6(2)(g) The supporting information document to this Proposal contains further information to support this analysis. A summary is outlined below.

Level of Risk

Option


N/A High Low


A Sustained Control Programme is the most appropriate programme. The operational aspects of the programme will not change in that an attempt will be made each year to control as much of the infestation as is possible.


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7.21 Mediterranean fanworm (Sabella spallanzanii) Why is it a threat? The Mediterranean fanworm (Sabella spallanzanii) forms dense colonies that could affect native species by competing for food and space. Recent studies have indicated impacts on the establishment of new generations of some species and on nutrient flow.

The presence of dense colonies of this species could also change the underwater scenery of an area, potentially impacting on dive tourism activities.

While Mediterranean fanworm has not yet been recorded to have had significant impacts on fisheries in New Zealand, it could become a nuisance to recreational and commercial fishers by clogging dredges and fouling other fishing gear when in high densities. This fanworm has been detected on some mussel farms in the Hauraki Gulf and Coromandel region recently. Because mussels and fanworms are filter feeders, the productivity of mussels may be affected if the fanworm infestations become high.

Reasons for proposing a Plan As Mediterranean fanworm becomes further established in other areas of New Zealand the risk to it becoming established in Marlborough is also increasing. Marlborough delivers around 62% of New Zealand’s aquaculture production by tonnes and the aquaculture industry accounts for almost 6% to Marlborough’s regional GDP38. There are also natural environments and other fisheries (such as scallops) that could be impacted upon if Mediterranean fanworm became established.

Why the Plan is more appropriate than relying on voluntary actions Since 2008, Marlborough District Council has been in partnership with the Ministry for Primary Industries (MPI) and both Tasman District Council and Nelson City Council under the banner of the Top of the South Marine Biosecurity Partnership. The primary intent of the partnership has been to raise the profile of marine biosecurity (including education and awareness) as a means to reduce the risk or marine pests becoming established in the top of the south island.

Since the inception of this partnership and despite ongoing work programmes, research and information gathering, the invasive clubbed tunicate Styela clava has established in Picton, Waikawa and Duncan Bay, and three separate vessels have been detected carrying Mediterranean fanworm. This has shown that education alone is not the best approach to preventing the establishment of unwanted marine organisms. A programme in the new Plan is proposed to address the risk posed to Marlborough by Mediterranean fanworm.

7.21.1 Objective Over the duration of the Plan, prevent the establishment of Mediterranean fanworm (Sabella spallanzanii) in Marlborough to eliminate adverse effects on economic wellbeing, the environment and enjoyment of the natural environment.




38 NZIER Report (2015) - The economic contribution of marine farming in the Marlborough region


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Persons may be required to act where rules or statutory obligations dictate such.


Council may:

a) Provide general purpose education, advice, awareness and publicity activities targeted toward persons that operate within the marine environment.

b) Promote industry requirements and best practice to persons that operate in the marine environment.

c) Encourage any person to report any pests they find.

d) Facilitate or commission research.

3) Council Inspection and Service Delivery


a) Conducting in-water surveillance and/or inspection activities.

b) Carry out control using administrative powers of the Biosecurity Act 1993, if necessary.

7.21.2 Rules Rule 7.21.2.1 The owner or person in charge of a craft entering Marlborough must ensure that the fouling on the hull and niche areas of the craft does not exceed ‘light fouling’; unless:

i) The craft is required to enter Marlborough in an emergency relating to the safety of the craft and/or the health and safety of any person on the craft;

‘Light fouling’ is defined as: small patches (up to 100 millimetres in diameter) of visible fouling, totalling less than 5% of the hull and niche areas. A slime layer and/or goose barnacles are allowable fouling.


Rule 7.21.2.2 Any person who suspects to have observed Mediterranean fanworm (Sabella spallanzanii) in Marlborough shall notify Council within 24 hours of making the observation, detailing the location and situation of suspected pest.


Note: Mediterranean fanworm is also a notifiable organism by way of the Biosecurity (Notifiable Organisms) Order 2016. As such, reports to MPI will also be sufficient with respect to Rule 7.21.2.2.

Rule 7.21.2.3 The occupier of any place shall take all reasonable steps to destroy Mediterranean fanworm (Sabella spallanzanii) that is identified to be harbouring on that place unless a management plan has been put in place, and approved by Council.



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Explanation of the rules: The purpose of Rule 7.21.2.1 is in accordance section 73(5)(e) in it is prohibiting or regulating specified uses of goods that may promote the spread or survival of Mediterranean fanworm.

The prevalence of Mediterranean fanworm in other parts of New Zealand, including the key recreational vessel hubs of Auckland and Whangarei Harbour, means the arrival of craft into Marlborough that are carrying bio-fouling are the biggest risk to the achievement of the proposed Exclusion Programme.

The purpose of Rule 7.21.2.2 is in accordance with section 73(5)(p) in that it is requiring a person notify the suspected presence of Mediterranean fanworm to enable the management agency to determine or monitor the presence or distribution of the pest.

An Exclusion Programme relies upon preventing establishment of Mediterranean fanworm. For this to occur, early detection and intervention is crucial. While active surveillance will be part of the proposed management agency programme, passive surveillance and timely notification from all other persons will assist with detection and early intervention.

The purpose of Rule 7.21.2.3 is in accordance with section 73(5)(h) in that it is requiring an occupier of a place to destroy Mediterranean fanworm on that place.

The effective management of Mediterranean fanworm, if identified, requires both rapid and intensive management to occur both initially and over the course of the ensuing years to prevent establishment. While in most instances the initial response will be led by the management agency under a management plan, this rule will also place a baseline requirement upon the occupier of that place to remain vigilant and continue to play an active role in preventing establishment. The occupier may play a part in the agreed management plan in which case the baseline rule would not apply.


7.21.3 Analysis of the benefits and costs for Mediterranean fanworm

Background Mediterranean fanworm was first detected in New Zealand waters during 2008 in Lyttleton Harbour. While an Eradication Programme was initiated in Lyttleton by MPI (formally MAF Biosecurity NZ), subsequent detections of infestations in Waitemata Harbour, Auckland meant the eradication attempt for New Zealand was ceased in 2010 as it was deemed no longer feasible.

Since 2010, MPI has focused on supporting councils where new incursions of Mediterranean fanworm have been detected and also developing a domestic marine pathways management approach to help prevent spread.

In recent years, there has been numerous elimination programmes instigated in Northland, Coromandel, Tauranga, Gisborne, Nelson and Picton. Vessels have also been detected on occasions in the outer Marlborough Sounds, Picton Marina and in Waikawa Bay.

Current situation in 2017 There have been three vessels detected in Waikawa Bay, and one in Picton Marina, with various growth stages of Mediterranean fanworm present. The risks posed by all three vessels were managed in a timely manner. However, during non-regular surveillance work in Picton Marina during November 2014, a small number of specimens have been detected growing on a structure. This was the first record of Mediterranean fanworm on ‘substrate’ in Marlborough. An active elimination programme is in place for Picton Marina given it was detected very early.

As a result of the immediate threat, Council notified a Small-Scale Management Programme (SSMP) on 6 July 2017 for Mediterranean fanworm. It is the intent that if the proposed programme within the RPMP is adopted by Council, the SSMP will be, in effect, replaced by the RPMP programme.


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Given the prevalence of Mediterranean fanworm in particularly Auckland, the risk of a craft carrying specimens to Marlborough, and resulting in the establishment of this marine pest, is very high without intervention.

Level of analysis for Mediterranean fanworm Council has determined that a medium level of analysis be undertaken for Mediterranean fanworm. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.


Economic Threat to the viability of aquaculture production throughout the Marlborough Sounds if left to establish and spread.

Evidence of impacts since its discovery in New Zealand in 2008 is still not yet apparent. In 2015 the first appearances of Mediterranean fanworm occurring on mussel lines in the Coromandel Harbour and off Waiheke Island occured. While there have not been any known occurrences of Mediterranean fanworm severely affecting aquaculture activities in other parts of the world, the traits shown and observed in New Zealand have led to marine scientists urging a large degree of caution to those dismissing the potential of this species to cause impacts. It has an immense breeding capacity and the nature of its feeding mechanism means it filters high volumes of water and does so through creating a canopy effect. This differs to other fouling species that would compete more as a space competitor. The Marlborough Sounds contains vast soft sediment beds that harbour a scallop industry. The establishment of Mediterranean fanworm within these areas could also affect this fishery via both competition and nuisance through fouling dredging equipment.

Natural marine environment Being an aggressive fouling species, there is a threat to natural rocky reef marine environments and also substrates that are habitable.

Evidence of impacts since its discovery in New Zealand in 2008 are still not yet apparent or are still under study. However, anecdotal evidence from the Waitemata Harbour is showing that heavy fouling is apparent on in-water structures and vessels left untreated for some time. There has also been fouling of sub-tidal reefs. It was first detected in Australia in1964. Since then there have been studies conducted that have shown some impact on the natural environment. When forming dense patches on soft substrates, it was shown to have significant detriment impact on benthic fauna39. Similarity, in Port Phillip Bay, studies have shown the potential for changes to the denitrification process when Mediterranean fanworm reach high densities. This could in turn lead to a higher chance of eutrophic conditions occurring 40

39 Ross DJ, Longmore AR, Keough MJ (2007). Impacts of two introduced suspension feeders in Port Phillip Bay, Australia. Marine Ecology Progress Series 340: 41-53.


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Values The values protected by the prevention of Mediterranean fanworm becoming established are regional values. The marine environment is highly complex and it is difficult to attribute quantification of values specifically.








Regional community



Whilst not captured using the grouping model for assessing beneficiaries and exacerbators, the other major beneficiary with respect to the proposed programme is that of the aquaculture industry, in particular mussel farming.

Options to respond to Mediterranean fanworm Baseline: No RPMP In this scenario, the status quo would likely continue under a non-regulatory framework. Intervention would continue to be focused on education and awareness. There will continue to be vessels arrive from other parts of the country with infestations of Mediterranean fanworm and likely be harbouring animals. No routine surveillance would occur, other than that as part of response activities and usual passive surveillance and reports.

Control option(s): Exclusion: To prevent the establishment of the subject that is present in New Zealand but not yet established in an area.

Analysis for Mediterranean fanworm Council has determined that a medium level of analysis be undertaken for Mediterranean fanworm. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.

40 Ross DJ et al. (2013). Spatially variable effects of a marine pest on ecosystem function. Oecologia 172: 525-538.


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Benefit Option

No RPMP Exclusion

The prevention of Mediterranean fanworm becoming established and the resulting impact of that on aquaculture activities.


The prevention of Mediterranean fanworm becoming established and the resulting impact of that on natural marine environments.






Agency costs • Surveillance • Management • Administration • Education/awareness

- MDC $135,000 MPI $28,000

Vessel owner costs - additional vessel

maintenance

- $390,51541

Total - $553,515


Insignificant

Analysis An analysis has been carried out using the economic impacts of Mediterranean fanworm to the mussel farming industry - see Appendix 2.7 and 2.8. A summary and sensitivity analysis can be found below in Tables 7 and 8.

41 A calculated estimate using 1) Vessel traffic data into Marlborough ouitlind within Hayden et. al (2009) Vessel Movements within New Zealand – MPI Technical Paper No: 2014/04, 2) Data on vessel fouling levels collected by the Top of the South Marine Biosecurity Partnership and 3) Cost of maintaining vessels as detailed in the cost beenfit analysis supporting the Northland Regional Council Regional Pest and Pathway Management Plan.


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As a result, a conservative discount rate of 4% has been used by Council in the analyses supporting the applicable proposed programmes. This is less than that recommended by Treasury but considering the long term impacts of pest management programmes, the lower discount rate is more appropriate.

Table 7: Summary of economic analysis for Mediterranean fanworm

Level of Risk

Options

No RPMP Exclusion

Present Value Net Present Value (Regional contribution to GDP from mussel farming)

N/A Moderate

Present Value/Net Present Value (PV/NPV) 4% discount rate

$-374,461,830 $362,054,171

Probability of success (risk) 100% 50%

Present Value/Net Present Value (PV/NPV) $-374,461,830 $174,952,493

Table 8: Sensitivity analysis

Level of Risk

Options

No RPMP Exclusion

Present Value Net Present Value

Moderate

Risk adjusted PV/NPV (3%) - NZIER Social rate $-496,698,147 $233,642,892

Risk adjusted PV/NPV (4%) $-374,461,830 $174,952,493

Risk adjusted PV/NPV (6%) - Default Treasury rate $-220,588,378 $101,285,293




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$-468,077,287 $221,663,294


$-374,461,830 $174,952,493


$-280,846,372

$128,241,692

Proposed allocation of costs It is proposed that the majority of the programme costs are allocated to craft owners that will need to maintain the condition of hulls to a higher standard. This has been done by way of rules requiring the occupiers to ensure the hull of craft is not carrying biofouling at a level at which would be high risk for Mediterranean fanworm.





Level of Risk

Option

No RPMP Exclusion

N/A Moderate

Reason There are substantial infestations of Mediterranean fanworm in other parts of New Zealand. This is already creating pressure on Marlborough through the arrival of vessels with bio-fouling containing Mediterranean fanworm. There has also been the detection of a small number of animals in Picton Marina. If the active response in Picton Marina cannot eliminate that population, there is a risk of Mediterranean fanworm becoming established in Picton Marina. Second to that, if vessels continue to arrive into Marlborough carrying bio-fouling, there is a risk of that bio-fouling containing Mediterranean fanworm which could be a source of establishment.


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7.22 Moth plant (Araujia hortorum) Why is it a threat? Moth plant is a vigorous evergreen climber that will grow up to 6 metres high. It originates from tropical South America. It spreads by wind-borne seeds that are released from pods as they dry out and split during autumn and winter. Moth plant will smother native species and is a problem in gardens where it can become the dominant species. The plant is poisonous and its sap has an irritant effect on contact with the skin.

Reasons for proposing a Plan Moth plant has long been recognised as a highly invasive weed in natural ecosystem with the potential to become the next smothering vine in Marlborough’s ecosystems. Localised infestations exist throughout New Zealand where it is, in most parts, under intensive management by authorities or community groups.

Infestations in Marlborough are predominately located in urban Blenheim as a legacy of home gardening. There are then outlier sites in Port Underwood, Waikawa, Havelock, Renwick and Elie Bay. In total there have been 318 sites identified. Of these, at 138 sites, moth plant is believed to have been eradicated and is under a long term surveillance programme. The remaining 180 sites that form the priority for the programme are managed intensively each year.

Why the Plan is more appropriate than relying on voluntary actions The management of this species needs to be both strategic and intensive to prevent long term impacts. Because of this, it is more appropriate to be managed through a structured programme of delivery enabled by a Plan rather than relying on voluntary actions.

7.22.1 Objective Over the duration of the Plan, control moth plant (Araujia hortorum) in the Marlborough district to less than or equal to 2016 levels to minimise adverse effects on the environment and enjoyment of the natural environment.






a) Delivering a service to manage moth plant.









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Council may:






7.22.2 Rules Rule 7.22.2.1 Occupiers are required to notify Council of any new infestation of moth plant (Araujia hortorum) on land that they occupy within 5 working days of the initial observation.











7.22.3 Analysis of the benefits and costs for moth plant Background Moth plant was classified as a Total Control pest plant in the 2001 Regional Pest Management Strategy for Marlborough during the review process.

Department of Conservation and Council staff knew how invasive this plant could be if allowed to spread. Gardeners had been using moth plant to feed monarch butterflies in the Blenheim and Picton urban areas. Control operations commenced in 2001. An annual control regime commenced for all known infestations. Active surveillance and awareness activities also commenced to increase the quality of distribution data held by Council.

Current situation in 2017 All known infestations of moth plant are controlled every year. If plant numbers reduce to near zero levels, sites are placed under a longer term surveillance regime. Articles in local newspapers have resulted in the discovery of a lot of new infestations on properties in the region’s urban areas. There are only a handful of sites away from urban areas now.


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The recent lift in the volume of moth plant controlled was a result of a significant single infestation being discovered near Waikawa Marina in 2016/17. The positive recent trend has been the reducing number of active and monitoring sites.

Moth plant has not yet had the chance to invade natural areas. Moth plant control and surveillance operations are carried out in February/March to coincide with its flowering time. This is when plants are easiest to see amongst other vegetation. Plants found are hand pulled or cut and the stump treated with herbicide. Any fruiting pods found are bagged for destruction.

Figure 15: The trend in infestation levels of moth plant in Marlborough

Options to respond to moth plantBaseline: No RPMPIn this scenario no control of moth plant is undertaken, and the assumption is made that the plant becomes well-established and progresses toward full naturalisation in all susceptible areas in the long term.

Control option(s):1. Eradication Programme: In which the intermediate outcome for the programme is to reduce the



Level of analysis for moth plantCouncil has determined that a low level of analysis be undertaken for moth plant. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.

ImpactsMoth plant is a vigorous evergreen climber that will grow up to 6 metres high. It originates from tropical South America. It spreads by wind-borne seeds that are released from pods as they dry out and split during autumn and winter. Moth plant will smother native species and is a problem in gardens where it can become the dominant species. The plant is poisonous and its sap has an irritant effect on contact with the skin.


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Conservation and biodiversity values Smothers native vegetation.

Over time it will spread and occupy up to 10 % of 198,000 hectares of forest edge and forest habitats in Marlborough.








Regional community




Benefit Option


The prevention of moth plant infesting new areas and the resulting impact of that on environmental values.




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Programme Costs

Option


GST)


GST)


GST)


- $100,000+ $30,000


Total - $100,000+ $30,000


over time






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Risk that each option will not achieve the Objective 6(2)(g) The supporting information document to this Proposal contains further information to support this analysis. A summary is outlined below.

Level of Risk

Option


N/A High Low

Reason The level of risk of not achieving an eradication objective, within 10 years or even at a longer time scale, is very high. While there has been a dramatic increase in the number of sites in recent years, this reflects the emphasis Council staff has placed on surveillance. The number of plants being controlled is decreasing but the volume of plants being found remains relatively high. There is still a long way to go for this species to reach zero levels in Marlborough in accordance with the original objective of eradication.

It is proposed to manage moth plant under a Sustained Control Programme with the ability to reassess progress over time. Achieving the objective under this type of programme is achievable for Council.




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7.23 Mountain pine (Pinus mugo) Definition Includes all sub-species and botanical variants, such as Pinus mugo subsp. mugo, Pinus mugo subsp. uncinata and Pinus uncinata.

Why is it a threat? Mountain pine can have significant impacts on native ecosystems, particularly those low in stature, such as tussock and indigenous grasslands, alpine ecosystems and subalpine scrub. Mountain pine grows faster and taller than low-stature vegetation so can easily out-compete these species. Soil and soil fauna are also altered when wilding conifers replace native ecosystems.

Mountain pine can also adversely affect amenity and landscape values. These landscapes are important for tourism and large scale landscape changes can impact on the value gained from tourism in Marlborough.

In areas where there is long term, seasonal soil moisture deficits, dense mountain pine stands can contribute to reductions in surface water flows, potentially impacting on water availability and associated aquatic ecosystems.


In areas of extensive pastoral farming, mountain pine infestations adversely impact economic wellbeing by reducing available grazing and limited the options for future land use.

Reasons for proposing a Plan In Marlborough, it is recognised the first up task of managing mountain pine to sustainable levels is one best carried out through large scale collaborative programmes outside of the Plan (see Biosecurity Strategy). However, to ensure the achievements gained by investing in management (by a number of parties), a programme within a Plan can ensure the gains made are sustainable in the long term. As such, the proposed programme reflects this.

Why the Plan is more appropriate than relying on voluntary actions In essence, the previously mentioned collaborative management programmes are voluntary actions. Interested parties, including the Council, the Department of Conservation, the Ministry for Primary Industries (MPI), Land Information New Zealand, the community at large and other organisations recognise the importance of managing mountain pine. This culminated in the development of the New Zealand Wilding Conifer Management Strategy (2015) then subsequent Crown Funding administered by MPI to invest in the issue (the National Wilding Conifer Management Programme). Prior to this, local trusts, such as the Marlborough Sounds Restoration Trust and South Marlborough Landscape Restoration Trust, established through a community desire to take action for community good.

All of these aspects to mountain pine management as occurring under the banner of voluntary action.

However, management of mountain pine is a long game. Under all of the scenarios of intervention, there is a concern that up-front investment could be put at risk by a lack of voluntary actions being undertaken at an individual land occupier level. As such, it is proposed that this Plan acknowledges the success of voluntary action in one respect (the broad collaborative management approaches), but the Plan is more appropriate to address the long term sustainability of achievements made.

7.23.1 Objective Over the duration of this Plan, ensure the ongoing control of mountain pine within the Marlborough region in order to minimise adverse effects on the environment, enjoyment of the natural environment and economic wellbeing.


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Council may:






7.23.2 Analysis of the benefits and costs for mountain pine Background Mountain pine was planted in the high country of Marlborough during the era of soil conservation efforts. Over the following decades, the trees planted not only established but began to spread prolifically out onto surrounding land. Seed of mountain pine can be blown long distances during high wind events and wilding trees can bear cones on average after 8 years, beginning the cycle again.

Current situation in 2017 Mountain pine can be found where originally planted in the Branch/Leatham catchment and the Wye catchment (in particular the “Turkey’s Nest”). Spread has occurred predominately within the Branch/Leatham catchment.

Baseline: No RPMP In this scenario, no control of mountain pine is undertaken, and the assumption is made that the species continues to establish in new areas and no attempt is made to control original infestations.


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Control option(s): 1. Progressive Containment Programme: In which the intermediate outcome for the programme is

to contain or reduce the geographic distribution of the subject, or an organism being spread by the subject, to an area over time. This option is outlining all control requirements in detail, within the RPMP framework.


Level of analysis for mountain pine Council has determined that a low level of analysis be undertaken for mountain pine. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.


Environmental Mountain pine grows faster and taller than low-stature indigenous vegetation. Indigenous ecosystems that are at particular risk of invasion include: tussock and other indigenous grasslands; alpine ecosystems; subalpine, dryland and other scrub and shrublands; wetlands; turf communities and coastal margins, cliffs and bluffs. Once they have invaded, trees can shade out many native plant communities and can also change soil characteristics44.




Water Quantity Where there are significant changes to land cover within a catchment, such as a domination of mountain pine, surfaces water flows can be negatively affected. This is more pronounced in dry South Island catchments.





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Economic Once wilding mountain pine spreads onto extensive or marginal farmland, active control required may be difficult for the land owner/occupier to justify financially given the marginal worth of the land for grazing. This can result in a compounding reduction on land area available for extensive grazing.







Occupiers of land with the pest present


Regional community


4 Regional community Occupiers of land with the pest present




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Benefit Option


The prevention of mountain pine re-establishing and the resulting impact of that on environmental values.



The prevention of mountain pine re-establishing and the resulting impact of that on landscape values.

The prevention of mountain pine re-establishing and the resulting impact of that on catchment water yields.

The prevention of mountain pine re-establishing and the resulting impact of that on production values of pastoral land.


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No RPMP


Sustained Control


-

$20,000 $0


$100,000+ $500




Low, but increases








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Level of Risk

Option



Reason The effective management of mountain pine to a progressive containment objective within a RPMP programme would set a level of expectation that effective management was to occur. As a result, there is a real risk of political and/or public concern over cost that would adversely affect the implementation of the programme.





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7.24 Nassella tussock (Nassella trichotoma) Why is it a threat? Nassella tussock is a perennial tussock that originates from South America. It can grow up to 70 centimetres high and a mature plant can produce up to 120,000 seeds. These seeds have the potential to spread 10 kilometres in strong winds. The seed has the ability to remain viable in the soil for many years. Nassella tussock is well adapted to invade and smother other grassland species and is largely unpalatable to livestock. It will also compete with native species. If left unmanaged, due to the prolific nature of seed set, it will form large unpalatable monocultures and spread rapidly to un-infested areas.

Reasons for proposing a Plan Nassella tussock has a long history of recognition as a serious threat to dry pastoral systems since its introduction in the 1800s and recognition as a serious threat by the 1930s. In 1946 dedicated legislation was introduced which saw the formation of specific Nassella Tussock Pest Destruction Boards in North Canterbury and Marlborough. Under this historical programme, the infestations of nassella tussock in Marlborough were bought back to manageable levels using herbicides, cultivation, destocking, topdressing, pasture renewal, afforestation, burning and grazing with cattle. The biggest measure over that time was the use of labour to manually grub more scattered infestations.

Nassella tussock is now at manageable levels in Marlborough when compared with historical levels. However, due to the reproductive potential of the plant, ongoing suppression is needed to maintain populations at current levels to prevent economic damage.

There is a significant net benefit to the control of nassella tussock based on the potential for damage to Marlborough’s pastoral farming economy.

Why the Plan is more appropriate than relying on voluntary actions If control was left to the voluntary actions of occupiers and no control was undertaken, there is a real risk that adequate management would not occur. The inclusion of a programme for nassella tussock in the new Plan will ensure this pest plant is kept under sustained management across all infested areas.

7.24.1 Objective Over the duration of the Plan, control nassella tussock (Nassella trichotoma) in the Marlborough district to a population trend that is level or reducing to minimise adverse effects on economic wellbeing, the environment, and enjoyment of the natural environment.










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Council may:






7.24.2 Rules Rule 7.24.2.1 Occupiers shall destroy all nassella tussock (Nassella trichotoma) plants, on land that they occupy, each year before they produce seed, unless a management plan* approved by Council is in place.


*A management plan for the purposes of Rule 7.24.2.1 is an agreed plan between the occupier and Council that outlines how nassella tussock will be managed on the land they occupy and contain administration provisions relating to the maintenance of the plan.

Management plans will be dynamic and also available to the occupier for reference at any time via the online Property File system at Council.

Rule 7.24.2.2 Occupiers are required to notify Council of any new infestation of nassella tussock (Nassella trichotoma) on land that they occupy within 5 working days of the initial observation.



Explanation of the rule: The purpose of Rule 7.24.2.1 is in accordance with section 73(5)(h) in that all occupiers within an infestation of nassella tussock are being required to take specified actions to prevent the pest increase to levels affecting productivity or neighbouring properties.




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7.24.3 Analysis of the benefits and costs for nassella tussock

Background Nassella tussock infestations have been in Marlborough since 1906. In 1946 a statutory board was established to control the nassella tussock threat. In 1989 the Board was dissolved on the basis that nassella tussock infestations had been reduced to a controllable level. Central Government considered that the responsibility of the cost of its control should be borne by the land owner with Council enforcing the provisions of the Noxious Plants Act. A programme for nassella tussock developed in Marlborough’s Regional Pest Management Strategy since 1996 where it was described as a “Containment Control” pest plant.

Current situation in 2017 Nassella tussock is well established across the lower hill and rolling country of South Marlborough. The objective of the existing programme is “to prevent any increase in the distribution of nassella tussock and reduce infestations levels where possible”.

In total there are 579 properties known to have an infestation of nassella tussock. These properties cover 166,851 hectares or 13% of the Marlborough district. The extent of nassella tussock on these properties, of varying density, totals 53,397 hectares and in doing so covers 4.3% of the district.

All properties have a current obligation to destroy all plants each year before they produce seed as a means to keep populations under sustained management. Unfortunately, there has not been any direct monitoring of populations carried out under the existing Regional Pest Management Strategy for Marlborough so the level of compliance through Council inspections has been used as a proxy for the success of the programme. This method comes with many flaws but it has shown, in a coarse manner, the programme is ensuring the population is being managed adequately, but needs ongoing management into the future.

Options to respond to nassella tussock Baseline: No RPMP In this scenario no control of nassella tussock is undertaken, and the assumption is made that the plant becomes well-established and progresses toward full naturalisation in all susceptible areas in the long term.

Control option(s): Sustained Control Programme: In which the intermediate outcome for the programme is to provide for ongoing control of the subject, to reduce its impacts on values and spread to other properties.

Level of analysis for nassella tussock Council has determined that a medium level of analysis be undertaken for nassella tussock. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.

Impacts Nassella tussock is a perennial tussock that originates from South America. It can grow up to 70 centimetres high and a mature plant can produce up to 120,000 seeds. A small portion of those seeds have the potential to spread large distances in strong winds. The seed also has the ability to remain viable in the soil for many years. Nassella tussock is well adapted to invade and smother other grassland species and is largely unpalatable to livestock. It will also compete with native species. If left unmanaged, due to the prolific nature of seed set, it will form large unpalatable monocultures that can spread to nearby un-infested areas.


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Economic • Diminished pasture and livestock production.

Control of nassella tussock will minimise impacts on the 53,397 hectares currently infested and reduce the threat to the remaining to 276,603 hectares of pastoral habitat that could become infested. Further quantification can be found within the background data and assumptions of the economic analysis in Appendix 2.10.








Regional community




Benefit Option

No RPMP Sustained Control

The prevention of nassella tussock building back to levels that cause economic damage to pastoral systems.

No programme cost The benefit under a Sustained Control Programme will remain constant throughout the life of the Plan, with no end point.


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Programme Costs

Option


GST)



- $220,000

Land occupier costs - $1,334,925

Total - $1,554,925


over time

Insignificant

Analysis An analysis has been carried out using the economic impacts of nassella tussock to pastoral systems - see Appendix 2.9 and 2.10. A summary and sensitivity analysis can be found below in Tables 9 and 10.



As a result, a conservative discount rate of 4% has been used by Council in the analyses supporting the applicable proposed programmes. This is less than that recommended by Treasury, but considering the long term impacts of pest management programmes, the lower discount rate is more appropriate.




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Table 9: Summary of economic analysis for nassella tussock

Level of Risk

Options

No RPMP Sustained Control (Council service delivery, in conjunction with

occupier)


N/A Moderate-Low

Present Value or Net Present Value (PV/NPV) (4% discount rate)

$-186,333,025 $43,268,589

Probability of success (risk) 100% 85%

Risk adjusted PV/NPV (4%) $-186,333,025 $23,543,229 Table 10: Sensitivity analysis

Level of Risk

Options

No RPMP Sustained Control (Council service delivery, in conjunction with

occupier)


Moderate-Low

Risk adjusted PV/NPV (3%) - NZIER Social rate $-233,227,867 $36,742,546

Risk adjusted PV/NPV (4%) $-186,333,025 $23,543,229

Risk adjusted PV/NPV (6%) - Default Treasury rate $-126,130,452 $8,276,496


$-279,499,538 $52,016,436


$-186,333,025 $23,543,229


$-93,166,512 $-4,929,979

Proposed allocation of costs It is proposed that the majority of the programme costs are allocated to occupiers of land that have nassella tussock infestations. This has been done by way of rules requiring the occupiers to manage nassella tussock. This aligns with the identification of beneficiaries and exacerbators.



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Risk that each option will not achieve the objective The supporting information document to this Proposal contains further information to support this analysis. A summary is outlined below. These risks were translated to weighing figures used as part of the economic analysis.

Level of Risk

Option


N/A Low

Reason The control tools that are available to manage nassella tussock are effective in keeping infestations ‘in check’. This allows for ongoing control at levels that reduce real and future impacts.




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7.25 Parrots feather (Myriophyllum aquaticum) Why is it a threat? Parrots feather is a stout hairless perennial semi-aquatic plant that originates from South America. It was introduced to New Zealand as an ornamental aquarium plant. It will grow up to 2 metres in length. It can emerge up to 15 centimetres above the water. It will grow in freshwater ponds, dams, ditches, lakes and streams up to 2 metres deep. It forms tangled mats of vegetation which impede drainage, displace native vegetation and disrupt recreational activities.

Reasons for proposing a Plan Parrots feather has long been recognised as a highly invasive aquatic weed, originally used as an ornamental aquarium plant, that has established itself in waterways around the country. Localised infestations exist throughout New Zealand where it is, in most parts, under intensive management by authorities or community groups.

Infestations in Marlborough have been found in two natural waterways and a number of smaller garden pond type scenarios. Only three sites within the broader Ōpaoa River system continue to harbour active infestations, with all others under a longer term surveillance programme. Unfortunately, the dynamic nature of waterways and the biological nature of parrots feather make complete eradication difficult.


7.25.1 Objective Over the duration of the Plan, control parrots feather (Myriophyllum aquaticum) in the Marlborough district to less than or equal to 2013 levels to minimise adverse effects on the environment and enjoyment of the natural environment.






a) Delivering a service to manage parrots feather grass in liaison with the occupier.









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Council may:






7.25.2 Rules Rule 7.25.2.1 Occupiers are required to notify Council of any new infestation of parrots feather (Myriophyllum aquaticum) on land that they occupy within 5 working days of the initial observation.











7.25.3 Analysis of the benefits and costs for parrots feather Background In 2000 parrots feather was discovered in Ruakanakana (Gibsons) Creek near Renwick. Parrots feather had not been seen in Marlborough since 1990 when it had been found in Fultons Creek. Surveillance work was carried out by Council staff to gain a better understanding of the plant’s distribution in the region. It was subsequently found at a number of other sites.

Parrots feather became a Total Control pest plant in the Regional Pest Management Strategy for Marlborough in 2001.

All known infestations have been controlled annually using a number of methods including; hand pulling and spot spraying with glyphosate. Since 2008/2009 the herbicide GarlonTM 360 has been used. In early 2013, old carpet was trialled on an area in Gibsons Creek to see whether this had any smothering effect on the infestation.


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The infestations have been extensive in the waterways and it has been difficult to count the number of individual plants controlled each year. The amount of herbicide used for controlling the infestations has been recorded. In 2012/2013 the infestation was small enough for the first time to estimate the number of plants controlled.

Current situation in 2017There are two current sites where parrots feather continues to be found annually. These are Ruakanakana (Gibsons) Creek near Renwick and the lower Ōpaoa River. All other historical sites are visited a minimum of once every five years to detect any re-emergence of plants.

Control operations and surveillance activities are carried out in February when water temperatures are highest and rainfall is at its traditionally lowest frequency.

The water levels in Ruakanakana (Gibsons) Creek can affect the success of the control efforts. With rainfall in the headwaters of the Wairau and/or Waihopai catchments, inputs via the Southern Valleys Irrigation Scheme can cause the level of Gibsons Creek to rise. This also introduces silt which can increase turbidity of the water making it difficult to find the plants.

As can be seen below, a substantial new site was detected within a backwater near Rose’s overflow.This resulted in an application of initial herbicide and the site being entered into ongoing management.

Figure 16: The trend in infestation levels of parrots feather in Marlborough

Options to respond to Parrots FeatherBaseline: No RPMPIn this scenario no control of parrots feather is undertaken, and the assumption is made that the plant becomes well-established and progresses toward full naturalisation in all susceptible areas in the long term.


infestation level of the subject to zero levels in an area in the short to medium term. This programme would most closely align to the current Total Control programme in the Regional Pest Management Strategy for Marlborough 2012. To achieve eradication all sites would be visited more frequently over a season.


180


Level of analysis for parrots feather Council has determined that a low level of analysis be undertaken for parrots feather. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.

Impacts Parrots feather is a stout hairless perennial semi-aquatic plant that originates from South America. It was introduced to New Zealand as an ornamental aquarium plant. It will grow up to 2 metres in length. It can emerge up to 15 centimetres above the water. It will grow in freshwater ponds, dams, ditches, lakes and streams up to 2 metres deep. It forms tangled mats of vegetation which impede drainage, displace native vegetation and disrupt recreational activities.


Economic, conservation and recreational values. It could potentially affect all land owners with lakes, streams, wetlands, drains or ponds on their property. Invades and displaces native vegetation. Impedes drainage and causes economic impact on production land via increased risk of flooding.

At risk habitat is 2,360 hectares.








Regional community




Benefit Option


The prevention of parrots feather infesting new areas and the resulting impact of that on environmental




181

Costs of each option 6(2)(d)

Programme Costs

Option


GST)


GST)


GST)


- $40,000+ $10,000


Total - $40,000+ $10,000


over time





Risk that each option will not achieve Objective 6(2)(g) The supporting information document to this Proposal contains further information to support this analysis. A summary is outlined below.

Level of Risk

Option


N/A High Low


There is a lower level of risk that Council will be able to maintain a very low density of parrots feather in Marlborough.




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7.26 Purple loosestrife (Lythrum salicaria) Why is it a threat? Originating from Europe, western Asia and North Africa purple loosestrife was introduced to New Zealand as an ornamental garden plant. It was first recorded in the wild in 1958.

Purple loosestrife destroys wetland and marginal habitats. It forms large, tall, impenetrable stands that exclude all other species. This can reduce food sources for many fish and bird species. It encourages an increase in sedimentation leading to waterway blockages and flooding. It has the potential to become a major weed in wetlands, swamps, lakesides, rivers and streams. Purple loosestrife is a prolific seeder. Mature plants can produce over 2 million seeds. These are dispersed by water and on contaminated machinery, soil, livestock and hay.

Reasons for proposing a Plan Purple Loosestrife has been recognised by the IUCN as being within the Top 100 of the worst invasive species globally. It invades primarily wetland habitats including river and stream banks, pond edges, lakes and roadside ditches.

In Marlborough, while there have been 17 sites identified, 10 of these have been cultured plants in urban gardens. These are believed to have been eradicated and now sit under a longer term surveillance programme. The remaining seven sites form the annual management programme given they initially involved plants growing in a wild state. All of these sites contain very few plants and are under intensive management.

Why the Plan is more appropriate than relying on voluntary actions With so few known sites, the management of this species needs to be both strategic and intensive. Because of this, it is more appropriate to be managed through a structured programme of delivery enabled by Plan rather than relying on voluntary actions.

7.26.1 Objective Over the duration of the Plan, control purple Loosestrife (Lythrum salicaria) in the Marlborough district to less than or equal to 2016 levels to minimise adverse effects on the environment and enjoyment of the natural environment.






a) Delivering a service to control purple loosestrife in liaison with the occupier.





183






Council may:






7.26.2 Rules Rule 7.26.2.1 Occupiers are required to notify Council of any new infestation of purple loosestrife (Lythrum salicaria) on land that they occupy within 5 working days of the initial observation.












184

7.26.3 Analysis of the benefits and costs for purple loosestrife

BackgroundA Council staff member discovered a plant growing in a Blenheim urban garden in 2007. The plant was removed and the site was entered into a surveillance regime. Since then, several new infestations have been found in other Blenheim urban gardens, but of more concern, other locations on the margins of waterways elsewhere within the district. All of these infestations have been entered into an ongoing control and surveillance regime, irrespective of the current ‘Surveillance’ category. This is because of the fact purple loosestrife is recognised by the IUCN Invasive Species Specialist Group as one of the top 100 most invasive species within the world51.

Current situation in 2017Purple loosestrife is currently a surveillance pest plant in the 2012 Regional Pest Management Strategy for Marlborough, but managed in the same way as species within the total control category.

Purple loosestrife has been found on 17 sites within Marlborough. All eight active and monitoring sites of purple loosestrife are visited annually between February and March when it flowers. Any plants found are either removed for destruction by hand or sprayed with a suitable herbicide. Any plants that are removed for destruction are disposed of through deep burial at landfill. The remaining 11 sites, many of which are urban gardens within Blenheim, are entered into a longer term surveillance system that integrates well into the moth plant programme that is focussed on urban Blenheim.

Figure 17: The trend in infestation levels of purple loosestrife in Marlborough

51 http://www.issg.org/worst100_species.html. Accessed 5 Spetember 2017.

http://www.issg.org/worst100_species.html


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Options to respond to Purple loosestrife Baseline: No RPMP In this scenario no control of purple loosestrife is undertaken, and the assumption is made that the plant becomes well-established and progresses toward full naturalisation in all susceptible areas in the long term.




Level of analysis for purple loosestrife Council has determined that a low level of analysis be undertaken for purple loosestrife. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.

Impacts Originating from Europe, western Asia and North Africa purple loosestrife was introduced to New Zealand as an ornamental garden plant. It was first recorded in the wild in 1958.

Purple loosestrife destroys wetland and marginal habitats. It forms large, tall, impenetrable stands that exclude all other species. This can reduce food sources for many fish and bird species. It encourages an increase in sedimentation leading to waterway blockages and flooding. It has the potential to become a major weed in wetlands, swamps, lakesides, rivers and streams. Purple loosestrife is a prolific seeder. Mature plants can produce over 2 million seeds. These are dispersed by water and on contaminated machinery, soil, livestock and hay.


Values held within wetlands and waterways • Reduce food sources for fish and bird species. • Waterway blockages, increasing

sedimentation.

Very large. All freshwater systems in both north and south Marlborough would be susceptible to invasion along their margins. The internationally significant wetland of Waikārapi Lagoon (Vernon Lagoon) and other regionally significant wetlands on the Wairau Plain.


186








Regional community




Benefit Option


The prevention of purple loosetrife infesting new areas and the resulting impact of that on environmental values.




Programme Costs

Option


GST)



GST)


- $100,000+ $10,000


Total - $100,000+ $10,000


over time



187





Level of Risk

Option


N/A High Low

Reason Purple loosestrife is very limited in distribution. Council will continue to visit the sites where plants continue to be found, undertake control, and search surrounding areas. However, the seed of this plant is very long-lived. It is evident the plant is very persistent in an area and could still be being cultivated. This results in high risk that control to zero density would not be achieved.

Purple loosestrife is very limited in distribution. Council will continue to visit the sites where plants continue to be found, undertake control, and search surrounding areas. By visiting all known active sites each year, and placing the remainder under longer term surveillance, Council will be able to maintain and possibly continue to see a decline in numbers of plants over the next 10 years.




188

7.27 Rabbits (Oryctolagus cuniculus) Why are they a threat? The feral rabbits are a small to medium sized herbivore that originates from Europe. Feral rabbits were released in New Zealand in the late 1700s and 1800s as a food source. They quickly adapted to New Zealand’s conditions and have thrived in our environment.

High feral rabbit population levels:

a) Affect soil and water quality;

b) Have a detrimental impact on economic production; and

c) Increase the risk of soil erosion.

Factors such as topography, climate, aspect and altitude all contribute to the variation in the feral rabbit population.

Reasons for proposing a Plan Feral rabbits are a pest species entrenched in the Marlborough landscape. Given the large area of land that can be prone to population build-up, all landholders need to suppress feral rabbit numbers and keep them supressed to avoid both landscape degradation and impacts on pastoral production.

Why the Plan is more appropriate than relying on voluntary actions If control was left to the voluntary actions of occupiers and no control was undertaken (or ad hoc management), there is a real risk that adequate management would not occur across the wider landscape. The inclusion of a programme for rabbits in the new Plan will ensure this pest animal is kept under sustained management.

7.27.1 Objective Over the duration of the Plan, control feral rabbits (Oryctolagus cuniculus) in the Marlborough district to a population trend that is level or reducing to minimise adverse effects on economic wellbeing and the environment.










189








Council may:






7.27.2 Rules Rule 7.27.2.1 Occupiers shall destroy feral rabbits (Oryctolagus cuniculus), on land that they occupy, to ensure population levels are not maintained higher than the respective Maximum Allowable Levels (see Table 11) for a period of time greater than 12 months.


Table 11: Maximum allowable rabbit populations

Sub-Regions Maximum Allowable Population Level Modified McLean Scale (see Appendix 3)

Upper Awatere/Clarence Map 9 Level 4

Remainder of area within district Level 3

Explanation of the rule: The purpose of Rule 7.27.2.1 is in accordance with section 73(5)(h) in that all occupiers that have rabbits on land they occupy are being required to take specified actions to prevent the pest increase to levels affecting productivity or neighbouring properties.



190

Map 9: Rabbit programme - Upper Awatere/Clarence


191

7.27.3 Analysis of the benefits and costs for rabbitsBackgroundThe Council’s Regional Plant Pest Management Strategy became operative on 1 July 1996, while the Regional Rabbit Pest Management Strategy became operative on 1 July 1997. The Biosecurity Act 1993 required these strategies to be reviewed within 5 years. Council decided to review the Regional Rabbit Pest Management Strategy along with the Regional Plant Pest Management Strategy for efficiency, and to incorporate both strategies into one policy document to be referred to as the “Regional Pest Management Strategy”.

Rabbits were included in the Marlborough Regional Pest Management Strategy for Marlborough in 2001.

The most rabbit prone areas of Marlborough are:

a) Upper Awatere Valley;

b) Waihopai Valley;

c) Clarence Catchment;

d) Parts of the mid-Wairau Valley;

e) Dashwood area; and

f) the coastal country between Blind River and Ward.

These areas have a history of a rabbits building to problem levels in the past.

At present, rabbit populations are significantly lower than in the past due to the effect of Rabbit Haemorrhagic Disease (RHD). However, populations can build even in the presence of RHD due to increased levels of immunity and this was seen from 2005-2010.

Current situation in 2017In recent years (2012-2017), climatic conditions have not been favourable for rabbit survival, including in the more highly prone areas. Coupled with continued activity of RHD, this has meant landholders have been able to keep on top of numbers. This has been reflected in both the Council trend data and property inspection results. As climatic conditions fluctuate, suitable conditions will return at some stage and may result in another build-up. Council continues a regional programme of carrying out property inspections to ensure numbers are being suppressed and being involved in ongoing research (e.g. tracking RHD immunity levels).

Figure 18: The trend in rabbit population levels in Marlborough from 1989-2017


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Options to respond to rabbits Baseline: No RPMP In this scenario no concerted or coordinated control of rabbits is undertaken, and numbers build to levels affecting productivity and create cross-boundary issues.

Control option(s): Sustained Control Programme: In which the intermediate outcome for the programme is to provide for ongoing control of the subject, to reduce its impacts on values and spread to other properties.

Level of analysis for rabbits Council has determined that a low level of analysis be undertaken for rabbits. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.

Impacts The rabbit is a small to medium sized herbivore that originates from Europe. Rabbits were released in New Zealand in the late 1700s and 1800s as a food source. They quickly adapted to New Zealand’s conditions and have thrived in our environment.

High rabbit population levels:

a) Affect soil and water quality;

b) Have a detrimental impact on economic production; and

c) Increase the risk of soil erosion.

Factors such as topography, climate, aspect and altitude all contribute to the variation in the rabbit population. These factors have been put together to generate an indication of rabbit proneness as part of the original application process to import RHD. A summary of this can be found in Table 12.

Table 12: Rabbit proneness classes

Note: There are exclusions for waterbodies and urban areas

Sub Region Area of land in rabbit proneness class (ha) 52 Total

Negligible Low Moderate High Extreme

Upper Awatere/Molesworth/Clarence

9,302 194,238 29,895 27,099 3,810 265,450

Rest of the district 351,326 337,296 82,820 1,074 -- 786,018

Total 360,628 531,534 112,715 28,173 3,810 1,051,468

52 Keer, I.G.C and Ross, W.D 1990. Rabbit Management in Central Otago. Classification of land for rabbit proneness. Contract report for the Minstry of Agriculture and Fisheries.


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Damage to pasture, crops, pine tree plantations.

Damage to soil resulting in stability issues and increased risk of erosion.

There is 31,983 hectares of high or extreme rabbit prone land in Marlborough. It is this land, where rabbits have the propensity to build to high numbers, that holds the greatest risk of soil erosion.

Increased threat to the health and integrity of natural ecosystems and habitats. In Marlborough, this predominantly includes tall and short tussock grassland.

Rabbits, even in low numbers, may be a conservation pest in tall tussock grassland communities where grazing reduces tussock cover and stature. There is 109,607 hectares of tall tussock grassland in Marlborough. In short tussock grassland communities, some palatable native plants, such as blue tussock (Poa colensoi) and hard tussock (Festuca novae-zelandiae) are adversely affected by rabbits53








Regional community



53 Norbury, D. 1996. The effects of rabbits on conservation values. Department of Conservation, Science for Conservation: 34.


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Benefit Option


Prevention of damage to pasture, crops, pine tree plantations.

No programme costs The benefit under a Sustained Control Programme will remain constant throughout the life of the Plan, with no end point.

Prevention of damage to soil resulting in stability issues and increased risk of erosion.


Reduction in threat to the health and integrity of ecosystems and habitats within the semi-arid lands.


Reduction in the spread of exotic grasses and herbs, providing niches for less competitive native species54.

Rabbits can be beneficial to some conservation values in short tussock grassland communities.

The benefit could reduce if rabbits are controlled in areas where some rabbit grazing pressure is beneficial to native communities.






- $80,000

Land occupier costs - $150,000

Total - $230,000


Insignificant

54 Norbury, D. 1996. The effects of rabbits on conservation values. Department of Conservation, Science for Conservation: 34.


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Level of Risk

Option


N/A Low-Moderate

Reason There are adequate controls available to effectively management rabbit populations. Occupiers will, in most instances, comply with obligations through pest management practises as part of their farming business plan. However, if rabbit populations build to high levels, the cost of control may mean some degree of risks to compliance. Some control tools can be perceived by the community at large as being inhumane (e.g. use of toxins) or do not support the approach (e.g. use of new RHD virus strains).




196

7.28 Reed sweet grass (Glyceria maxima) Why is it a threat? Reed sweet grass is a large rhizomatous grass which originates from Europe. It grows along the margins of a wide range of both flowing and standing watercourses. It forms dense, impenetrable stands of emergent marginal vegetation which:

a) Impede drainage;

b) Displace native vegetation; and

c) Disrupt recreational activities.

It has been implicated in the cyanide poisoning of livestock.

Reasons for proposing a Plan Reed sweet grass infestations exist throughout New Zealand and is commonly under management in recognition of the threat it poses. By impeding drainage it has the capability of increasing flooding risk for both upstream and adjoining land. If infested, margins of waterways may also become less suitable as habitat for native fauna and native flora becoming excluded.

In Marlborough, infestations are localised but occur in the Grovetown Lagoon, at Langleydale, within the confines of Roberts and Pukaka Drains, within Ruakanakana (Gibsons) Creek and within a wetland on Rangitoto ki te Tonga/D’Urville Island.

Why the Plan is more appropriate than relying on voluntary actions With few known sites, the management of this species needs to be both strategic and intensive. Because of this, it is more appropriate to be managed through a structured programme of delivery enabled by a Plan rather than relying on voluntary actions.

7.28.1 Objective Over the duration of the Plan, control reed sweet grass (Glyceria maxima) in the Marlborough district to less than or equal to 2017 levels to minimise adverse effects on economic wellbeing, the environment and enjoyment of the natural environment.






a) Delivering a service to manage reed sweet grass in liaison with the occupier.









197


Council may:






7.28.2 Rules Rule 7.28.2.1 Occupiers are required to notify Council of any new infestation of reed sweet grass (Glyceria maxima) on land that they occupy within 5 working days of the initial observation.











7.28.3 Analysis of the benefits and costs for reed sweet grass

Background Reed sweet grass has been managed by Council as a Containment Control pest plant in the current Regional Pest Management Strategy for Marlborough. The objective has been to contain infestations to the heavily infested Grovetown Lagoon. All other known infestation have been subject to intense management efforts.

Since 2007, control operations at most sites have brought infestation levels down substantially. A reduction in the Grovetown Lagoon infestation has also been possible and large operations were carried out in 2009. Since 2009, all sites (including Rangitoto ki te Tonga/D’Urville Island) have been ranged thoroughly with all sites subject to control efforts. Levels of infestation have been static.

In 2013, a substantial “new” (old but recently discovered) infestation was discovered on Northbank Road at Langleydale. This site is now included in the Council programme.


198

Current situation in 2017There are 11 sites recorded by Council as having reed sweet grass in Marlborough. Eight of these sites are active and require annual management. The remaining three sites fall under a longer term surveillance programme.

The reed sweet grass programme has currently plateaued. Infestation levels continue to remain steady and manageable. There are some advances being made both in the effectiveness of herbicides and the way on-ground works are scheduled. This has allowed multiple ‘runs’ to be carried out. Improvement to the management of on-ground work has also meant an improvement in data collection to track progress.

Figure 19: The trend in infestation levels of reed sweet grass (using herbicide usage as a proxy for population levels) in Marlborough

Options to respond to reed sweet grassBaseline: No RPMPIn this scenario no control of reed sweet grass is undertaken, and the assumption is made that the plant becomes well-established and progresses toward full naturalisation in all susceptible areas in the long term.




Level of analysis for reed sweet grassCouncil has determined that a low level of analysis be undertaken for reed sweet grass. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.


199

Impacts Reed sweet grass is a large rhizomatous grass which originates from Europe. It grows along the margins of a wide range of both flowing and standing watercourses. It forms dense, impenetrable stands of emergent marginal vegetation which:

a) impede drainage;

b) displace native vegetation; and

c) disrupt recreational activities.

It has been implicated in the cyanide poisoning of livestock.

Reed sweet grass infestations exist throughout New Zealand. It is a troublesome drainage weed in many areas of New Zealand. Indications are that this species is still spreading. In Marlborough, infestations exist in the Grovetown Lagoon, Roberts Drain, Ruakanakana (Gibsons) Creek and on Rangitoto ki te Tonga/D’Urville Island. It is suspected that there are more sites of this invasive species in the district.


Conservation and recreation values Reed sweet grass appears capable of causing damage to Marlborough’s conservation and recreation values. It could potentially affect all land owners with lakes, streams, wetlands, drains or ponds on their property. Invades and displaces native vegetation. Impedes drainage and causes economic loss of production.









Regional community




200


Benefit Option


The prevention of reed sweet grass infesting new areas and the resulting impact of that on environmental values.

No programme cost There are ecosystems throughout Marlborough that would be vulnerable to invasion from reed sweet grass. Preventing reed sweet grass expanding its range and infestation levels will provide benefit to natural ecosystems from another invasive species. The benefit under an Eradication Programme will increase to an end point when the objective is able to be achieved.

There are ecosystems throughout Marlborough that would be vulnerable to invasion from reed sweet grass. Preventing reed sweet grass expanding its range and infestation levels will provide benefit to natural ecosystems from another invasive species. The benefit under a Sustained Control Programme will remain constant throughout the life of the Plan, with no end point.


Programme Costs

Option


GST)


GST)



- $80,000+ $25,000

Land occupier costs -

Total - $80,000+ $25,000


over time






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Level of Risk

Option


N/A High Low

Reason The level of risk of not achieving an eradication objective, within 10 years or even at a longer time scale, is very high. However, there is a general concern that this organism may have a wider distribution in Marlborough than is currently known. If Council considers total control is the preferred option, any future new sites that are detected will influence an increase in control costs.

Reed sweet grass continues to be a well-established pest species that Council is currently attempting to suppress. Given the length of time this species has been in Marlborough, there is also the chance other infestations may be found. Recent improvements to the operational delivery of the programme are showing promise. Annual control work can achieve better results. Council is proposing to manage reed sweet grass under a Sustained Control Programme. The operational aspect of the current programme is not intended to change with all sites subject to intensive management.




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7.29 Rooks (Corvus frugilegus) Why are they a threat? Rooks are large, black birds with a violet-blue glossy sheen that originate from Europe. They will forage on fields of cereal at all stages of the crop and will tear up large areas of pasture in search of grass grub and other invertebrates. Rookeries (nests) are generally built in pine or eucalyptus trees, although they have been found in poplar and walnut trees. When established, rookeries may approach several hundred birds.

Reasons for proposing a Plan In decades past, there have been both rooks and rookeries established in Marlborough. These have now been eradicated from the region with only the odd occurrence of a small number of birds. They may have flown across the Cook Strait from established populations in the lower North Island (although under intensive management) or linked with the very small number of birds still known to be in Canterbury.

By ensuring these birds maintain profile as threats to Marlborough through a programme within a Plan, Marlborough can endeavour to maintain a rook-free status into the future.

Why the Plan is more appropriate than relying on voluntary actions Without a Plan in place, rooks could quite easily be seen as “just another bird” by members of the community where voluntary actions rest. If not addressed early, birds that may come to Marlborough (for example, from the lower North Island), could form rookeries and develop a breeding population. Therefore a Plan is seen as more appropriate.

7.29.1 Objective Over the duration of the Plan, prevent the establishment of rooks (Corvus frugilegus) in the Marlborough district to prevent future impacts on economic wellbeing.






a) Delivering a service to respond and investigate sightings of rooks in Marlborough.

b) Delivering a service to control rooks if required, in liaison with the occupier.





Land owners and/or occupiers or other persons may be required to act where rules or statutory obligations dictate the presence of pests is to be reported.


Council may:




203

7.29.2 Rules Rule 7.29.2.1 Any person is required to notify Council of any suspected rook (Corvus frugilegus) within 5 working days of making the initial observation.


Explanation of the rule: The purpose of this rule is for entire community to assist Council with surveillance. Requiring people to notify Council of sightings, in addition to Council’s own surveillance, will assist Council in achieving the objective of the programme. Birds new to the district can be found and control plans prepared if persisting in an area to prevent establishment.








7.211.3 Analysis of the benefits and costs for rooks Background Marlborough has always had low numbers of rooks in the past. The current objective in the Regional Pest Management Strategy for Marlborough 2012 is to eradicate rooks from Marlborough. This has been achieved.

Given the inherent risk and threat of rooks, it is now believed feasible to prevent rooks establishing once again in Marlborough.

Current situation in 2017 The last control operation was carried out at a rookery in 2005. Since that control operation rooks have not been known to be established in Marlborough. Only the odd transient bird has been seen. The current objective has been achieved.

Options to respond to rooks Baseline: No RPMP In this scenario no facilitation of sightings or control of rooks detected is undertaken.

Control option(s): Exclusion Programme: In which the intermediate outcome for the programme is to prevent the establishment of the subject that is present in New Zealand but not yet established in an area.

Analysis for rooks Council has determined that a low level of analysis be undertaken for rooks. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.


204

Impacts Rooks are large, black birds with a violet-blue glossy sheen, which originates from Europe. They will forage on fields of cereal at all stages of the crop and will tear up large areas of pasture in search of grass grub and other invertebrates. Rookeries (nests) are generally built in pine or eucalyptus trees, although they have been found in poplar and walnut trees. When established, rookeries may approach several hundred birds.


The prevention of rooks establishing in Marlborough that would result in impacts on pastoral productivity, arable cropping and vegetable production.

The impact could potentially be borne by the following sectors of the Marlborough agricultural industry: • Pastoral farming - use of forage crops • Arable - grain production • Vegetable production - multitude of crops

grown for both fresh and processed produce. It is not practical to quantify these sectors other than to state they all form a large part of the agricultural economy in Marlborough.








Regional community




Benefit Option

No RPMP Exclusion

The prevention of impacts on pastoral productivity, arable cropping and vegetable production.



205






- $500


Total - $500


Insignificant





Level of Risk

Option

No RPMP Exclusion

N/A Low

Reason Rooks are large, black birds with a very loud, distinctive call. Birds should not go un-noticed with an adequate awareness programme in the district. Control tools and techniques are available to prevent establishment.




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7.30 Rough horsetail (Equisetum hyemale) Why is it a threat? Rough horsetail is an erect, colony-forming primitive fern-ally. The stems have a distinctive black collar at the joints. It forms an extensive network of underground rhizomes.

This plant spreads rapidly and can re-sprout from underground stems . It can form pure stands in a wide range of damp habitats, and preventing the growth and regeneration of native species. These stands can also hinder or even block watercourses that can lead to an increased risk of flooding.

Reasons for proposing a Plan In 2013, a landholder near Renwick, Marlborough reported an unusual looking plant sprouting in a paddock adjacent to a drainage ditch. This was confirmed to be rough horsetail. A subsequent site was discovered within a prize-winning garden bordering the same waterway, upstream. Since then, two further infestations have been found; in urban Blenheim and inside an old swimming pool near Seddon. These two sites are essentially contained but could still be targeted for management.

The risk in Marlborough is for the initial infestations or any new infestations yet to be discovered becoming established throughout Ruakanakana Creek (Gibsons Creek) and into the Omaka then Ōpaoa Rivers.


7.30.1 Objective Over the duration of the Plan, control rough horsetail (Equisetum hymale) in the Marlborough district to a population trend that is level or reducing, to minimise adverse effects on economic wellbeing, the environment, and enjoyment of the natural environment.






a) Delivering a service to control rough horsetail in liaison with the occupier.









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Council may:






7.30.2 Rules Rule 7.30.2.1 Occupiers are required to notify Council of any new infestation of rough horsetail (Equisetum hymale) on land they occupy within 5 working days of the initial observation.











7.30.3 Analysis of the benefits and costs for rough horsetail Background In 2013, a landholder near Renwick, Marlborough, reported an unusual looking plant sprouting in a paddock adjacent to a drainage ditch. This was confirmed to be rough horsetail. A subsequent site was discovered within a prize-winning garden bordering the same waterway, upstream. Since then, two further infestations have been found; in urban Blenheim and inside an old swimming pool near Seddon. These two sites are essentially contained but can still be targeted for management.

Current situation in 2017 There are four sites confirmed in Marlborough to date. Control work has been initiated at two of the sites located in a drainage channel that feeds Ruakanana (Gibsons) Greek, near Renwick.

Plants within the Equisetum genus are notoriously difficult to control, partly due to their almost prehistoric morphology and then their extensive underground stem systems. The infestations near Renwick have been used to fine tune and test different control techniques.


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Options to respond to rough horsetail Baseline: No RPMP In this scenario no control of rough horsetail is undertaken, and the assumption is made that the plant becomes well-established and progresses toward full naturalisation in all susceptible areas in the long term.




Analysis for rough horsetail Council has determined that a low level of analysis be undertaken for rough horsetail. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.


Recreational values Smothers native aquatic vegetation on the margins of waterways and impedes recreational activities and water flow.


Conservation values Threaten wetlands in the district. Native wetland and aquatic species.



There are 160 kilometres of Council maintained watercourses and drains on the Wairau floodplain.








Regional community




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Benefit Option


The prevention of rough horsetail building in density, infesting new areas and the resulting impact of that on environmental values.



The prevention of rough horsetail building in density, infesting new areas and the resulting impact by way of increased flood damage.




Programme Costs

Option


GST)


GST)


GST)


- $20,000+ $6,000


Total - $20,000+ $6,000


over time






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Level of Risk

Option


N/A High Low

Reason The level of risk of not achieving an eradication objective, within 10 years or even at a longer time scale, is very high. Given the biological nature of rough horsetail, It is very unlikely that this species will be eradicated.

There is a lower level of risk that Council will be able to maintain a very low density of rough horsetail in Marlborough.




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7.31 Saffron thistle (Carthamus lanatus) Why is it a threat? Saffron thistle is an erect annual herb, which originates from Europe and Asia. It has woody stems, prominent spines and small yellow flower heads. It can form impenetrable strands if left uncontrolled and has the potential to devalue fibre, injure stock and interfere with cereal harvesting.

Reasons for proposing a Plan (individually) Saffron thistle has long been recognised as a highly invasive pastoral weed that thrives in Marlborough’s warm dry climate. Localised infestations exist throughout New Zealand where it is, in most parts, under intensive management by authorities.

Historically, infestations in Marlborough have been found across the district and recorded on 21 separate properties. In 2016, there are only 10 properties under intensive management with the other 11 under a longer term surveillance programme. Unfortunately, saffron thistle had a very long-lived seedbank and flare-ups have occurred where for suspected climatic reasons, the seed can strike and plants attempt to re-establish.

Why the Plan is more appropriate than relying on voluntary actions With a limited number of sites, the management of this species needs to be both strategic and intensive to ensure the long-lived seed is not allowed to be produced and enter the seedbank at a given site. Because of this, it is more appropriate to be managed through a structured programme of delivery enabled by a Plan rather than relying on voluntary actions.

7.31.1 Objective Over the duration of the Plan, control saffron thistle (Carthamus lanatus) in the Marlborough district to less than or equal to 2016 levels to minimise adverse effects on economic wellbeing, the environment and enjoyment of the natural environment.






a) Delivering a service to manage saffron thistle in liaison with the occupier.









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Council may:






7.31.2 Rules Rule 7.31.2.1 Occupiers are required to notify Council of any new infestation of saffron thistle (Carthamus lanatus) on land that they occupy within 5 working days of the initial observation.











7.31.3 Analysis of the benefits and costs for saffron thistle Background Saffron thistle became a Total Control pest plant in the Regional Pest Management Strategy for Marlborough in 1996. Prior to 1996 it was managed under the Noxious Plants Act. There were several infestations at the time in the Wairau Valley, the Awatere Valley and one site in the Marlborough Sounds.

These infestations have been controlled annually. Some sites were visited up to three times between January and April. In the earlier years all plants were grubbed and the seed heads removed for destruction. Since 2011, instead of grubbing, plants have been sprayed with a residual herbicide in attempt to exhaust any seedbank in the soil.


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Current situation in 2017There are eight active sites in Marlborough and a further two under monitoring (where no plants have been found in recent years). One of the active sites is a result of a recent ‘flare-up’ of a where no plants had been found for a number of years prior.

With saffron thistle having such a long-lived seed, ongoing monitoring of sites and surveillance of historical sites will be crucial to ensure no ‘flare-ups’ occur. This is where good data collection and analysis ensures all sites are managed accordingly.

Figure 20: The trend in infestation levels of saffron thistle in Marlborough

Options to respond to saffron thistleBaseline: No RPMPIn this scenario no control of saffron thistle is undertaken, and the plant spreads throughout the region.




Level of analysis for saffron thistleCouncil has determined that a low level of analysis be undertaken for saffron thistle. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.


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Impacts Saffron thistle is an erect annual herb, which originates from Europe and Asia. It has woody stems, prominent spines and small yellow flower heads. It can form impenetrable strands if left uncontrolled and has the potential to devalue fibre, injure stock and interfere with cereal harvesting.


Diminished pasture and livestock production It is estimated that saffron thistle will infest up to 10% of more intensive pastoral land uses (LUC55 Classes I, II and III), and 5% of pastoral hill/high country land (Classes IV, V and VI). Modelling of this scenario assumed spread characteristics of between 50 and 200 metres for mature plants, and between 5 and 10 years to reach its maximum density at a site in an uncontrolled situation.

Degradation of areas where people recreate due to the very coarse and sharp/spiky nature of the plants

Marlborough has large recreational areas that would also be ideal habitat for saffron thistle to establish. Such areas include the Wither Hills Farm Park and the Taylor River Reserve.








Regional community




Benefit Option


The prevention of saffron thistle building in density or infesting new areas and the resulting impact of that on pastoral productivity.





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Programme Costs

Option


GST)


GST)


GST)


- $100,000+ $23,000


Total - $100,000+ $23,000


over time






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Level of Risk

Option


N/A High Low


There is a lower level of risk that Council will be able to maintain a very low density of saffron thistle in Marlborough. With a robust system in place, and with saffron thistle continuing to be of limited distribution, the number of plants controlled continues to decline. However, based on the number of active sites and the volume of plants still being controlled each year, it is proposed to manage saffron thistle under a Sustained Control Programme.




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7.32 Scots pine (Pinus sylvestris) Why is it a threat? Scots pine can have significant impacts on native ecosystems, particularly those low in stature, such as tussock and indigenous grasslands, alpine ecosystems and subalpine scrub. Scots pine grows faster and taller than low-stature vegetation so can easily out-compete these species. Soil and soil fauna are also altered when wilding conifers replace native ecosystems.

Scots pine can also adversely affect amenity and landscape values. These landscapes are important for tourism and large scale landscape changes can impact on the value gained from tourism in Marlborough.



In areas of extensive pastoral farming, scots pine infestations adversely impact economic wellbeing by reducing available grazing and limited the options for future land use.

Reasons for proposing a Plan In Marlborough, it is recognised the first up task of managing scots pine to sustainable levels is one best carried out through large scale collaborative programmesprojects outside of the Plan. However, to ensure the achievements gained by investing in management (by a number of parties), a programme within a Plan can ensure the gains made are sustainable in the long term. As such, the proposed programme reflects this.

Why the Plan is more appropriate than relying on voluntary actions In essence, the previously mentioned collaborative management projects are voluntary actions. Interested parties, including the Council, the Department of Conservation, the Ministry for Primary Industries (MPI), Land Information New Zealand (LINZ), the community at large and other organisations, recognise the importance of managing scots pine. This culminated in the development of the New Zealand Wilding Conifer Management Strategy (2015) then subsequent Crown Funding administered by MPI to invest in the issue (the National Wilding Conifer Management Programme). Prior to this, local trusts, such as the Marlborough Sounds Restoration Trust and South Marlborough Landscape Restoration Trust established through a community desire to take action for community good.

All of these aspects to scots pine management as occurring under the banner of voluntary action.

However, management of scots pine is a long term game. Under all of the scenarios of intervention, there is a concern that up-front investment could be put at risk by a lack of voluntary actions being undertaken at an individual land occupier level. As such, it is proposed that the new Plan acknowledges the success of voluntary action in one respect (the broad collaborative management approaches), but also addresses the long term sustainability of achievements made.

7.32.1 Objective Over the duration of this Plan, ensure the ongoing control of scots pine within the Marlborough region in order to minimise adverse effects on the environment, enjoyment of the natural environment and economic wellbeing.





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Council may:






7.32.2 Analysis of the benefits and costs for scots pine Background Scots pine (Pinus sylvestris) was planted in the hill country of Marlborough during the era of soil conservation efforts and woodlot planting, particular in the Hanmer Springs and Molesworth areas. Over the following decades, the trees planted not only established but began to spread prolifically out onto surrounding land. Seed of scots pine can be blown long distanced during high wind events and wilding trees can bear cones in 6-8 years beginning the cycle again.

Current situation in 2017 Scots pine can be found where originally planted in the Branch/Leatham catchment, Wye catchment and Molesworth (Tarndale). Prolific spread has occurred surrounding the original Tarndale plantings and also within and on the margins of the Branch/Leatham catchment. Other smaller isolated plantings have been anecdotally noted in other locations within Marlborough.

Baseline: No RPMP In this scenario, no control of scots pine is undertaken, and the assumption is made that the species continues to establish in new areas and no attempt is made to control original infestations.

Control option(s): 1. Progressive Containment Programme: in which the intermediate outcome for the programme is




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Analysis for scots pine Council has determined that a low level of analysis be undertaken for scots pine. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.


Environmental Scots pine grows faster and taller than low-stature indigenous vegetation. Indigenous ecosystems that are at particular risk of invasion include: tussock and other indigenous grasslands; alpine ecosystems; subalpine, dryland and other scrub and shrublands; wetlands; turf communities and coastal margins, cliffs and bluffs. Once they have invaded, trees can shade out many native plant communities and can also change soil characteristics56.




Water Quantity Where there are significant changes to land cover within a catchment, such as a domination of scots pine, surfaces water flows can be negatively affected. This is more pronounced in dry South Island catchments.





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Economic Once wilding scots pine spreads onto extensive or marginal farmland, active control required may be difficult for the land owner/occupier to justify financially given the marginal worth of the land for grazing. This can result in a compounding reduction on land area available for extensive grazing.









Regional community




Benefit Option

No RPMP Progressive Containment Sustained Control The prevention of scots pine re-establishing and the resulting impact of that on environmental values.






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The prevention of scots pine re-establishing and the resulting impact of that on landscape values.

The prevention of scots pine re-establishing and the resulting impact of that on catchment water yields.

The prevention of scots pine re-establishing and the resulting impact of that on production values of pastoral land.



No RPMP


Sustained Control


-

$20,000 $0


$100,000+ $500





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Low, but increases







Level of Risk

Option



Reason The effective management of scots pine to a progressive containment objective within a RPMP programme would set a level of expectation that effective management was to occur. As a result, there is a real risk of political and/or public concern over cost that would adversely affect the implementation of the programme.





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7.33 Senegal tea (Gymnocoronis spilanthoides) Why is it a threat? Senegal tea is a perennial, semi-aquatic herb which grows to 1.5 metres when flowering. It originates from Central and South America. It spreads by vegetative fragmentation. New plants are produced from stem nodes and by seed. It forms dense floating mats which can quickly cover waterbodies. They exclude native flora and fauna and impede water flows and navigation and recreational activities.

Reasons for proposing a Plan Senegal tea is a highly invasive semi-aquatic plant species. It has only been detected on two occasions in Marlborough with both cases being confined within managed gardens and subsequently removed. The detection of this highly invasive species in Marlborough demonstrates the need for vigilance. This to ensure the species maintains a profile and Council has the ability to act quickly in the vent it is detected again. It is because of these reasons that a programme within the Plan is being proposed.

Why the Plan is more appropriate than relying on voluntary actions The threat form this species is more appropriate to be managed through a structured programme of delivery enabled by a Plan rather than relying on voluntary actions.

7.33.1 Objective Over the term of the Plan, prevent the establishment of Senegal tea (Gymnocoronis spilanthoides) in the Marlborough district to prevent future impacts on environmental values and the enjoyment of the natural environment.





a) Delivering a service to respond and investigate reports of Senegal tea in Marlborough.

b) Delivering a service to control Senegal tea if found, in liaison with the occupier.









Council may:




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7.33.2 Rules Rule 7.33.2.1 Occupiers are required to notify Council of any new infestation of Senegal tea (Gymnocoronis spilanthoides) on land they occupy within 5 working days of the initial observation.


Note: Historical distribution data is able to be viewed online via Council’s Smart Maps service.









7.37.3 Analysis of the benefits and costs for Senegal tea Background Senegal tea became a Total Control pest plant in the Regional Pest Management Strategy for Marlborough in 2007.

It was found by a Council staff member while they were carrying out surveillance work for parrots feather. It was found at two sites, one in an urban garden pond and the other in a Rural garden pond. Both sites were eradicated by hand removal over the next few years.

Since the eradication of the two previously known infestations in 2004 and 2006, no further evidence of Senegal tea has been found in Marlborough. Council continued to inspect the previously infested sites and look for it while carrying out aquatic pest surveillance.


225

Current situation in 2017Senegal tea infestations have been successfully eradicated at two locations in Marlborough. One site is in urban Blenheim and the other site is on a Rural property west of Renwick.

Figure 21: The trend in infestation levels of Senegal tea in Marlborough

Options to respond to Senegal teaBaseline: No RPMPIn this scenario no facilitation of reports or control of Senegal tea detected is carried out.

Control option(s):ExclusionThe infestation levels at both sites reached zero levels some years ago. Periodic surveillance of these sites has continued with no plants found in 8 and 10 years respectively.

Level of analysis for Senegal teaCouncil has determined that a low level of analysis be undertaken for Senegal tea. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.


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Impacts Senegal tea is a perennial, semi-aquatic herb which grows to 1.5 metres when flowering. It originates from Central and South America. It spreads by vegetative fragmentation. New plants are produced from stem nodes and by seed. It forms dense floating mats which can quickly cover waterbodies. They exclude native flora and fauna and impede water flows and navigation and recreational activities.


Recreational values Smothers native aquatic vegetation on the margins of waterways and impedes recreational activities and water flow.


Conservation values Threaten wetlands in the district. Native wetland and aquatic species.










Regional community




Benefit Option


The prevention of Senegal tea establishing in Marlborough and the resulting impact of that on environmental values.




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- $500


Total - $500


Insignificant





Level of Risk

Option

No RPMP Exclusion

N/A Low/Medium

Reason With no known infestations in Marlborough, any new infestation is likely to be small in nature with adequate tools available to address a small localised infestation. There is an ongoing background risk of the illegal trade and/or distribution of plants (in breach of section 52 and 53 of the Biosecurity Act 1993) that may include Senegal tea.




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7.34 Spartina (Spartina anglica) Why is it a threat? Spartina is a sward forming grass that originates from the United Kingdom. It grows from underground rhizomes. The rhizomes break off and establish elsewhere. It will also spread via seed. It grows in estuaries and displaces native plants and animals of salt marshes and mud flats. It can cause accelerated sedimentation in estuaries. It can also impede river water flows.

Reasons for proposing a Plan Up until 2004, the management of spartina was undertaken by the Department of Conservation in the Marlborough region with the exception of the Havelock and Kaituna estuaries. At the time, a containment policy was in place.

It was not until a feasibility study jointly initiated by the Department of Conservation and Council indicated that eradication of spartina was indeed feasible. That set in motion the aerial spraying of all entrenched infestations in 2004 and a structured maintenance programme for all known infested areas with the new objective of eradication. This programme continues to this day. That new objective also aligns with a 2012 feasibility study produced by the Department of Conservation that highlights eradication from the entire South Island, which is also now seen as feasible and something the Department of Conservation are working towards.

While no infestations are located on private land, there remains the risk of new infestations being detected that could jeopardise the programme objective. As a result, a Plan will both cement the Council support for the programme and ensure the programme is protected from any inaction from occupiers in the event a new infestation outside of the coastal marine area is detected.


7.34.1 Objective By the end of the term of this Plan, spartina (Spartina anglica) on all known sites in the Marlborough district will have been controlled to zero density to prevent adverse effects on the environment, and enjoyment of the natural environment.






a) Delivering a service in conjunction with the Department of Conservation to control spartina in liaison with the occupier (if applicable).





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Council may:






7.34.2 Rules Rule 7.34.2.1 Occupiers are required to notify Council of any new infestation of spartina (Spartina anglica) on land they occupy within 5 working days of the initial observation.



Explanation of the rule: The purpose of this rule is for occupiers to assist Council with surveillance. Requiring occupiers to notify Council of new sites and plants on their properties in addition to Council’s own surveillance will assist Council and the Department of Conservation in achieving the objective of the programme. New infestations will be able to be controlled and incorporated into the programme.








7.34.3 Analysis of the benefits and costs for spartina Background The Department of Conservation made a submission to Council during a review of the 2001 Regional Pest Management Strategy for Marlborough. The submission requested assistance from Council with an Eradication Programme for spartina. The proposal was to aerial spray an extensive infestation in the Havelock Estuary. A feasibility study was carried out by an environmental consultant. The study identified that the eradication of spartina was a real possibility. The control of spartina was already being carried out by Department of Conservation staff using herbicide on all known infestations outside of the Havelock Estuary.


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Spartina became a surveillance pest plant in the 2001 Regional Pest Management Strategy for Marlborough.

Council and the Department of Conservation applied for resource consent to use herbicide for the control of spartina across Marlborough. This resource consent was granted with conditions. Consultation with the Havelock community took place in 2003. In 2004 the Department of Conservation and Council began funding control of spartina. An aerial application of herbicide was undertaken in the Havelock Estuary. This achieved 95% control.

Through the review of the Regional Pest Management Strategy for Marlborough in 2007, spartina was lifted to a Total Control pest plant with an objective of Eradication.

Council and the Department of Conservation continue to fund an Eradication Programme for spartina. It is carried out by Department of Conservation staff and contractors annually. All infestations are ranged every year in January/February. Control work must be carried out at low tide to allow any spartina plants sprayed to absorb the herbicide before the tide comes in again. Any plants found are GPS recorded and sprayed with herbicide. The herbicide used (Gallant™) gives excellent control of spartina and is selective to grass species. It does not damage the native jointed rush and wetland species present in the tidal zones.

Spartina infestations have reduced significantly. The personnel undertaking the control work can range an area shoulder-to-shoulder and not find a single plant.

Current situation in 2015There have been twelve geographic areas recorded in Marlborough as having an infestation of spartina.Since management began by the Department of Conservation, two of these areas are now historical (Vernon Lagoon and Okiwi Bay) and only receive periodic surveillance. Since 2007, the remaining ten areas form the target for ongoing control work under the jointly funded Council and Department of Conservation Eradication Programme.


231

Figure 22: The trend in infestation levels of spartina (using spray mix as a proxy) from 2005-2011

Figure 23: The trend in infestation levels of spartina from 2012-2017

Options to respond to spartinaBaseline: No RPMPIn this scenario no control of spartina is undertaken, and the plant re-establishes within available habitat.


infestation level of the subject to zero levels in an area in the short to medium term. This programme would most closely align to the current Total Control Programme in the Regional Pest Management Strategy for Marlborough 2012.


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Level of analysis for spartina Council has determined that a low level of analysis be undertaken for spartina. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.

Impacts Spartina is a sward forming grass that originates from the United Kingdom. It grows from underground rhizomes. The rhizomes break off and establish elsewhere. It can also spread via seed. It grows in estuaries and displaces native plants and animals of salt marshes and mud flats. It can cause accelerated sedimentation in estuaries. It can also impede river water flows.


Conservation values Invades and displaces native vegetation and accelerates sedimentation in estuaries.









Regional community




Benefit Option


The prevention of spartina re-establishing in areas where it has been effectively removed and infesting new areas, resulting in the impact on environmental values.




233


Programme Costs

Option


GST)


GST)


GST)


- MDC $22,000 DOC $55,000

MDC $15,000 DOC $30,000


Total - $77,000 $45,000


over time




Rationale for the allocation of costs It has been recognised that, due to the location of the infestations of spartina in Marlborough, being often located within coastal marine area in the Marlborough Sounds, the Department of Conservation wishes to co-manage this species. As such, a significant portion of the cost of the programme has been allocated to the Department of Conservation. This is in recognition of the Department of Conservation being both a beneficiary and exacerbator (passive) for this species



234


Level of Risk

Option No RPMP Eradication Sustained Control

N/A Low/Medium Low Reason The level of risk of not

achieving an Eradication objective, within 10 years or even at a longer time scale, is low/medium. The number of plants being found has been steadily decreasing since the Havelock Estuary aerial control work. It has now got to a stage where, on average, less than 50 plants are being found. However, the effectiveness of existing control methodologies to achieve eradication within the term of the Plan may be questionable

There is a lower level of risk of being able to maintain a very low density of spartina in Marlborough The number of plants being found has been steadily decreasing since the Havelock Estuary aerial control work. It has now got to a stage where, on average, less than 50 plants are being found. This low level of infestation will be easily maintained, or even reduced over time.



This is due to the fact the risk of not achieving an Eradication objective is comparably lower than other species. This is supported by substantial feasibility studies conducted by the Department of Conservation. A Sustained Control Programme would enable lower costs, but would need to continue in perpetuity.


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7.35 Tall wheat grass (Thinopyrum ponticum) Why is it a threat? Tall wheat grass is a rigid, erect, perennial tussock-forming grass (termed as bunchgrass in the USA) growing taller than other Thinopyrum species, up to 3 metres tall. It is well adapted to seasonally flooded, salt influenced habitats, especially those where summer droughts are frequent (Champion 2015)61.

The main infested area in Marlborough is adjacent to the lower Ōpaoa River and seeds are likely to disperse through drainage channels to this and the Waikārapi Lagoons and Te Pokohiwi/Boulder Bank which is an important conservation area. Values threatened by tall wheat grass invasion would be likely displacement of a range of salt marsh vegetation types that include the at-risk declining species Mimulus repens by tall growing monocultures of this grass. The conservation area also supports possibly the greatest diversity of wetland birds in New Zealand and the tall dense vegetation likely to result from invasion would affect a number of birds by reducing foraging and nesting areas, increasing shelter for predators and increasing fire risk (Champion 2015).

Reasons for proposing a Plan Tall wheat grass is still within the very early stages of naturalisation in Marlborough. Early indications are that adequate control tools are available to implement a control programme to place this species under management. It has been evident that human mediated spread is possible so by using a structured programme within a Plan, this risk can be mitigated through education and complementary regulation.


7.35.1 Objective Over the duration of the Plan, control tall wheat grass (Thinopyrum ponticum) in the Marlborough district to less than or equal to 2016 levels to minimise adverse effects on economic wellbeing, the environment, and enjoyment of the natural environment.






a) Delivering a service to control tall wheat grass in liaison with the occupier.




61 Champion P 2015. Environmental Impact Assessment for tall wheat grass (Thinopyrum ponticum). Small Envirolink Grant prepared for Marlborough District Council.


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Council may:






7.35.2 Rules Rule 7.35.2.1 Occupiers are required to notify Council of any new infestation of tall wheat grass (Thinopyrum ponticum) on land that they occupy within 5 working days of the initial observation.












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7.35.3 Analysis of the benefits and costs for tall wheat grass Background Tall wheat grass was first recorded as naturalised in New Zealand in 2013, based on a collection from Dillons Point Road. Prior to this, tall wheat grass had been imported to New Zealand and subjected to pastoral, revegetation and soil conservation trials by Grasslands and Botany Divisions of the Department of Science and Industrial Research (DSIR) in a range of high country South Island sites, including Molesworth, Cromwell, Alexandra, Tekapo and Tara Hills (Omarama), from the 1920s to the late 1950s. A more recent trial was conducted by AgResearch Grasslands in Palmerston North from 1989 to 1991. Marlborough plants were sourced from seed collected at Tara Hills. Plants used in the South Island trials have apparently not persisted, but the status of the plants used in the recent Palmerston North trial needs investigation.

Since the detection of the naturalisation in 2013, Council has instigated comprehensive surveillance within the surrounding area to delimit the naturalised infestation. Trials have also been put in place to assess the best control tool for this species.

An Environmental Impact Assessment was commissioned by Council in 2015 and carried out by NIWA Scientist Dr Paul Champion. This assessment supported other findings originating from Australia in that tall wheat grass is an invasive species that threaten saline communities.

Current situation in 2017 There are 17 sites confirmed in Marlborough. 13 of these sites are within the Dillons Point area, surrounding and including the property where the original trials were conducted. This property is the most heavily infested. The remaining four sites are located at Cobb Cottage Road. This infestation looks to be a result of human assisted spread where hay has been fed out.

Preliminary trial work has indicated glyphosate effectively manages tall wheat grass. However, on the heavily infested property, the saline soils mean options for permanent removal are continuing to be developed.

Options to respond to tall wheat grass Baseline: No RPMP In this scenario no control of tall wheat grass is undertaken, and the assumption is made that the plant becomes well-established and progresses toward full naturalisation in all susceptible areas in the long term.




Level of analysis for tall wheat grass Council has determined that a low level of analysis be undertaken for tall wheat grass. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached


238


Environmental The displacement of a range of salt marsh vegetation types. Reducing foraging and nesting areas. Increasing shelter for predators. Increasing fire risk.

The Waikārapi Lagoon and Te Pokohiwi/Boulder Bank complex is comprised on approximately 2400 hectares of saltmarsh, tidal flats, sandspits and islands. The Waikārapi Lagoon boasts national ecological significance and some argue that it also meets the criteria for international importance. Over 90 bird species have been recorded from the area, with 27% of these listed as endangered, vulnerable or rare, e.g. black stilt (Himantopus novaezelandiae) and wrybill (Anarhynchus frontalis). The estuary is used by some bird species as a winter roosting site (e.g. black-fronted tern (Chilodonias albostriatus) and black-billed gull (Larus bulleri), while others use it for breeding (e.g. red-billed gull (Larus novaehollandiae scopulinus)). The estuary also hosts international migratory waders such as eastern bar-tailed godwits (Limosa lapponica baueri). Expansive salt marsh flats are a significant ecological feature of the estuary.62

Cultural The invasion of a tall, perennial exotic grass into areas of extremely high cultural significance within Waikārapi Lagoon and potentially on Te Pokohiwi/Boulder Bank.








Regional community



62 Berthelsen A, Gillespie P, Clement D, Peacock L 2015. State of the environment monitoring of Wairau Estuary. Prepared for Marlborough District Council. Cawthron Report No. 2741. 62 p. plus appendices.


239


Benefit Option


The prevention of tall wheat grass building in density, infesting new areas and the resulting impact of that on environmental and cultural values.




Programme Costs

Option


GST)


GST)


GST)


- $50,000+ $23,000


Total - $50,000+ $23,000


over time






240


Level of Risk

Option


N/A High Low/Medium

Reason Control methodologies to effectively remove tall wheat grass from an area indefinitely are still being refined. This is a new programme and also relatively new to the occupiers affected. The operational delivery may affect occupiers and how they are currently managing their property.

From preliminary trials, it is believed through the use of existing tools, infestations can be managed to reduce infestation size in the short term. This is a new programme and also relatively new to the occupiers affected. The operational delivery may affect occupiers and how they are currently managing their property.




241

7.36 Wallabies (Family Macropodidae) Why are they a threat? At high densities, wallabies can have significant adverse environmental effects. These include the prevention of regeneration of native bush, depletion of forest under-storey and possible impacts on water quality. Wallabies also damage tall tussock grasslands, including the inter-tussock vegetation that can become depleted with a consequent increase in bare ground and increased risk of soil erosion. Economic effects include damage to pasture with anecdotal evidence of complete clearance of cover in places. There is evidence of wallabies grazing on green feed crops particularly where these border suitable cover. Wallabies also damage exotic forests, particularly at the establishment stage, with damage being more serious in areas bordering native bush or scrub areas.

Reasons for proposing a Plan There are no known populations of wallabies established in Marlborough. As a result, no impacts are currently being felt either economically or environmentally. However, the threat from illegal liberation is real, with numerous instances of carcasses being dumped and/or evidence of young animals being hand raised.

An Exclusion Programme for wallabies within a Plan will highlight the risk of introduction and put in place clear penalties for attempts at illegal liberations.

Why the Plan is more appropriate than relying on voluntary actions Without a Plan in place, wallabies could quite easily be seen as a curiosity by members of the community, where voluntary actions would sit. If not profiled as a threat, there would be a far greater chance of wallabies being liberated and a population established. Therefore a Plan is seen as more appropriate.

7.36.1 Objective Over the duration of the Plan, prevent the establishment of wallabies (Family: Macropodidae) in the Marlborough district to prevent future impacts on economic wellbeing, the environment and enjoyment of the natural environment.






a) Delivering a service to respond and investigate sightings of wallabies in Marlborough.

b) Delivering a service to control wallabies if required, in liaison with the occupier.





Land owners and/or occupiers or other persons may be required to act where rules or statutory obligations dictate



242


Council may:



7.37.2 Rules Rule 7.37.2.1 All persons are required to notify Council of any suspected wallabies (Family: Macropodidae) observed within 5 working days of the initial observation.


Rule 7.37.2.2 No person shall have in their possession or keep in captivity on a place they occupy, any live wallabies (Family: Macropodidae).

Note: This rule does not derogate in any way from the statutory obligation of persons under section 52 and 53 of the Biosecurity Act 1993.


Explanation of the rule: The purpose of Rule 7.37.2.1 is for the entire community to assist Council with surveillance. Requiring people to notify Council of sightings, in addition to Council’s own surveillance, will assist Council in achieving the objective of the programme. Any animal(s) released or being kept illegally within the district can be found and managed appropriately to prevent establishment.

The purpose of Rule 7.37.2.2 is in accordance with section 73(5)(e) in that the possession of, and keeping of wallabies is seen as an activity that can affect measures taken to implement the Plan by attempting to introduce new animals to the Marlborough district, or increase the risk of captive animals escaping.


7.36.3 Analysis of the benefits and costs for wallabies Background Two species of wallaby are both well known as naturalised in New Zealand. These are the Dama wallaby (Macropus eugenii) and Bennett’s wallaby (Macropus rufogriseus rufogriseus) in the Rotorua and Waimate areas of New Zealand respectively. Other species of wallaby are known to occur on Kawau Island in the Hauraki Gulf near Auckland. Given the proximity of these populations, human mediated spread is the most likely way in which any species of wallaby will become established in Marlborough in the short term.

Marlborough has ideal and plentiful habitat for both Dama and Bennett’s wallabies. The forested environment of the Marlborough Sounds is well suited to the Dama and the extensive hill and high country of South Marlborough would be equally as receptive to Bennett’s. Any other species of wallaby would also find suitable niches within the region.


243

Current situation in 2017 There are no known populations of wallabies established in Marlborough.

In recent years, there has been instances where the threat of establishment has been highlighted through the actions of persons exhibited undesirable (or more commonly, ignorant) behaviour. There has been a case where a hand-raised wallaby had escaped enclosure and was observed in the wild. There have also been other cases of wallaby carcasses left on roads within areas conducive to live animals becoming established.

Options to respond to wallabies Baseline: No RPMP In this scenario no facilitation of sightings or control of wallabies detected is undertaken.

Control option(s) Exclusion Programme: In which the intermediate outcome for the programme is to prevent the establishment of the subject that is present in New Zealand but not yet established in an area.

Level of analysis for wallabies Council has determined that a low level of analysis be undertaken for wallabies. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.


244


The prevention of wallabies establishing in Marlborough that would result in impacts on pastoral productivity and forestry.

Wallabies cause losses in agricultural production from competition with sheep and some prevention of isolated damage to fodder crops (Warburton pers.com.) and impacts to young forestry seedlings during establishment. Wallabies cause losses in agricultural production from competition with sheep and some prevention of isolated damage to fodder crops (Warburton pers.com.) and impacts to young forestry seedlings during establishment (Warburton 198663). It is not practical to quantify these sectors other than to state that both the pastoral and forestry sector form a large part of the primary industry based economy of Marlborough. The impact by way of browsing competition and damage to planted forest seedlings would be large.

The prevention of wallabies establishing in Marlborough that would result in impacts on biodiversity values.

Given the multiple number of species that could establish in Marlborough, and the diverse natural ecosystem types across the region, the impacts can be framed under two primary facets: 1. Impacts of ecosystems values held with

landscapes in South Marlborough. 2. Impacts of ecosystem values held within the

forested landscapes of the Marlborough Sounds. South Marlborough Evidence from studies conducted in the Hunter Hills area of South Canterbury did highlight localised effects on biodiversity and indigenous vegetation communities. The localised areas (1-5 hectares) were predominantly in tall tussock grasslands where browsing damage was considerable. There is 109,607 hectares of tall tussock grassland in Marlborough. It is within these same ecosystems where South Marlborough has been recognised as one of five hot spots for endemic biodiversity. This endemism in South Marlborough is heavily weighted to plant species which could be at risk from the browse pressure from wallabies.

63 Warburton, B. 1986: Wallabies in New Zealand: history, current status, research, and management need. FRI Bulletin 114. Forest Research Institute, Christchurch. 29 p.


245

Marlborough Sounds The impact of wallaby browse within forest environments are well documented from the Rotorua area64 and from Kawau Island65. Within the Marlborough Sounds, the primary land cover types (and area for Marlborough as a whole) are: • Indigenous forest (212,798 hectares) • Manuka/kanuka (103,638 hectares) • Broadleaved indigenous hardwoods

(45,598 hectares) • Fernland (1466 hectares) While not all these land covers will hold significant biodiversity value, if wallabies species that thrive in these covers were to establish, the impact would be felt across a large area.








Regional community



64 Clements B 2006. Dama wallaby. Sustainabel Options Animal Control Fact Sheet 16. Environment Bay of Plenty, Whakatane.

65 Auckland Regional Council 2004. Animal Pests of the Auckland Region. Pest Facts 100. Auckland Regional Council, Auckland.


246


Benefit Option

No RPMP Exclusion

The prevention of impacts on pastoral productivity and forestry.


The prevention of impacts on biodiversity values.


The social benefit of having an easily accessible recreational hunting resource if wallabies were to establish.

The benefit would likely be realised through the liberation of animals in Marlborough and the establishment of a local population that could be hunted.

No benefit to be realised.






- $2,000


Total - $2,000


Insignificant





247


Level of Risk

Option

No RPMP Exclusion

N/A Medium

Reason Tools and techniques to detect wallabies at low densities are an acknowledged weakness in New Zealand. Animals are predominantly nocturnal and can evade detection easily in their ideal habitat of mixed pasture/scrub. There is a continued risk of illegal liberations of wallabies to create a ‘closer to home’ hunting resource.




248

7.37 Western white pine (Pinus monticola) Why is it a threat? Western white pine can have significant impacts on native ecosystems, particularly those low in stature such as tussock and indigenous grasslands, alpine ecosystems and subalpine scrub. Western white pine grows faster and taller than low-stature vegetation so can easily out-compete these species. Soil and soil fauna are also altered when wilding conifers replace native ecosystems.

Western white pine can also adversely affect amenity and landscape values. These landscapes are important for tourism and large scale landscape changes can impact on the value gained from tourism in Marlborough.



In areas of extensive pastoral farming, western white pine infestations adversely impact economic wellbeing by reducing available grazing and limited the options for future land use.

Reasons for proposing a Plan In Marlborough, it is recognised the first up task of managing western white pine to sustainable levels is one best carried out through large scale collaborative programmes/projects outside of the Plan. However, to ensure the achievements gained by investing in management (by a number of parties), a programme within a Plan can ensure the gains made are sustainable in the long term. As such, the proposed programme reflects this.

Why the Plan is more appropriate than relying on voluntary actions In essence, the previously mentioned collaborative management projects are voluntary actions. Interested parties, including the Council, the Department of Conservation, the Ministry for Primary Industries (MPI), Land Information New Zealand, the community at large and other organisations, recognise the importance of managing western white pine. This culminated in the development of the New Zealand Wilding Conifer Management Strategy (2015) then subsequent Crown Funding administered by MPI to invest in the issue (the National Wilding Conifer Management Programme). Prior to this, local trusts such as the Marlborough Sounds Restoration Trust and South Marlborough Landscape Restoration Trust established through a community desire to take action for community good.

All of these aspects to western white pine management as occurring under the banner of voluntary action.

However, management of western white pine is a long game. Under all of the scenarios of intervention, there is a concern that up-front investment could be put at risk by a lack of voluntary actions being undertaken at an individual land occupier level. As such, it is proposed that this Plan acknowledges the success of voluntary action in one respect (the broad collaborative management approaches), but the Plan is more appropriate to address the long term sustainability of achievements made.

7.37.1 Objective Over the duration of this Plan, ensure the ongoing control of western white pine within the Marlborough region in order to minimise adverse effects on the environment, enjoyment of the natural environment and economic wellbeing.





249















Council may:






7.37.2 Analysis of the benefits and costs for western white pine

Background Western white pine (Pinus monticola) was planted in the Wye catchment of Marlborough in the era of soil conservation efforts. Over the following decades, the trees planted not only established but began to spread prolifically out onto surrounding land. Seed of western white pine can be blown long distances during high wind events and as wilding trees can bear cones and produces seed, the cycle begins again.

Current situation in 2017 Western white pine is only known to occur both within and adjacent to (as wildings) the Wye reserve former Catchment Board plantings. During control operations surrounding the Wye reserve, wilding western white pine have been found up to 3 kilometres from the original planting areas.

While not prevalent in Marlborough in comparison to other species, there is evidence of this species being able to very capable of produce wildings in a manner that threatens surrounding areas.

Baseline: No RPMP In this scenario, no control of western white pine is undertaken, and the assumption is made that the species continues to establish in new areas and no attempt is made to control original infestations.


250

Control option(s): 1. Progressive Containment Programme: in which the intermediate outcome for the programme is



Level of analysis for western white pine Council has determined that a low level of analysis be undertaken for western white pine. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.

Impacts Identify impact Quantify impact Environmental Western white pine grows faster and taller than low-stature indigenous vegetation. Indigenous ecosystems that are at particular risk of invasion include: tussock and other indigenous grasslands; alpine ecosystems; subalpine, dryland and other scrub and shrublands; wetlands; turf communities and coastal margins, cliffs and bluffs. Once they have invaded, trees can shade out many native plant communities and can also change soil characteristics66.




Water Quantity Where there are significant changes to land cover within a catchment, such as a domination of western white pine, surfaces water flows can be negatively affected. This is more pronounced in dry South Island catchments.


66 Froude, V.A. 2011. Wilding conifers in New Zealand: Status Report. Prepared for the Ministry of Agriculture and Forestry. 67 Duncan MJ 1996. A methodology for identification of areas vulnerable to flow reductions because of afforestation. NIWA Christchurch Consultancy Report No CRC60512. Cited in Environment Canterbury Regional Council 2011. Christchurch. 68 Environment Canterbury Regional Council 2011. Canterbury Natural Resources Regional Plan.Chapter 5: water quantity. http://ecan.govt.nz/publications/Plans/nrrp-chapter-5-cover- main-text-operative-110611.pdf , Environment Canterbury RegionalCouncil. 214 p.


251

Economic Once wilding western white pine spreads onto extensive or marginal farmland, active control required may be difficult for the land owner/occupier to justify financially given the marginal worth of the land for grazing. This can result in a compounding reduction on land area available for extensive grazing.

There are three categories of land cover within the Land Cover Database (2012)69 that is associated with extensive grazing. These are low producing grassland, depleted grassland and tall tussock grassland. These three land cover classes total 246,583ha in the Marlborough region.








Regional community






252


Benefit Option


The prevention of western white pine re-establishing and the resulting impact of that on environmental values.



The prevention of western white pine re-establishing and the resulting impact of that on landscape values.

The prevention of western white pine re-establishing and the resulting impact of that on catchment water yields.

The prevention of western white pine re-establishing and the resulting impact of that on production values of pastoral land.


253



No RPMP


Sustained Control


-

$20,000 $0


$100,000+




Low, but increases








254


Level of Risk

Option



Reason The effective management of western white pine to a progressive containment objective within a RPMP programme would set a level of expectation that effective management was to occur. As a result, there is a real risk of political and/or public concern over cost that would adversely affect the implementation of the programme.



Most preferred option Sustained Control Programme (with the active management to occur outside of the RPMP under Collaborative Wilding Conifer Programmes, detailed within the Operational Plan.)


255

7.38 White-edged nightshade (Solanum marginatum) Why is it a threat? White-edged nightshade is a large shrub or tree with aggressive spines. It originates from North Africa. It will grow up to 3 metres high and will form dense thickets, which become impenetrable and displace preferred pasture species. It will also displace native species.

Reasons for proposing a Plan White-edged nightshade infestations exist throughout New Zealand and are commonly under management in recognition of the threat it poses. In Marlborough, this species is only known to occur within one geographical area in Beatrix Bay/Forsyth Bay in the Outer Pelorus Sound. A total of four properties are affected - one heavily infested surrounded by three with scattered infestations.

Given the serious threat this species poses, and the very limited extent, management through a Plan can ensure future impacts can be avoided over a larger area of Marlborough.

Why the Plan is more appropriate than relying on voluntary actions With so few infested properties, the management of this species needs to be both strategic and intensive. Because of this, it is more appropriate to be managed under a regulatory framework enabled by a Plan rather than relying on voluntary actions alone.

7.38.1 Objective Over the duration of the Plan, control white-edged nightshade (Solanum marginatum) in the Marlborough district (excluding the White-edged Nightshade Containment Area) to less than or equal to 2016 levels to minimise adverse effects on economic wellbeing, the environment and enjoyment of the natural environment.
















256


Council may:






7.38.2 Rules Rule 7.38.2.1 Occupiers shall destroy all white-edged nightshade (Solanum marginatum) plants, on land that they occupy before they produce seed, except in areas of land they occupy that falls within the White-edged Nightshade Containment Area (see Map 9), which is subject to Rule 7.38.2.2.


Rule 7.38.2.2 Occupiers of land within the White-Edged Nightshade Containment Area (see Map 9) shall destroy all white-edged nightshade (Solanum marginatum), on land they occupy before they produce seed, within 50 metres of the Containment Area boundary.


Rule 7.38.2.3 Occupiers are required to notify Council of any new infestation of white-edged nightshade (Solanum marginatum) on land that they occupy within 5 working days of the initial observation.


Note: Current distribution data, and the White-Edged Nightshade Containment Area boundaries are able to be viewed online via Council’s Smart Maps service.

Explanation of the rule: The purpose of Rule 7.38.2.1 is in accordance with section 73(5)(h) in that all occupiers without a heavy infestation are being required to take specified actions to prevent the pest establishing on that land.

The purpose of Rule 7.38.2.2 is in accordance with section 73(5)(h) in that the occupiers of land where heavy infestation occur are required to take specified actions to prevent spread pressure on the edges of the Containment Area.




257

Map 10: White-edged Nightshade Containment Area


258

7.38.3 Analysis of the benefits and costs for white-edged nightshade

Background White-edged nightshade became a progressive control pest plant in the Regional Pest Management Strategy for Marlborough in 1996. A single land occupier with an extensive infestation (the core property) was required to control a 100 metre boundary strip on external boundaries in the first year. Each year, a further 100 metres was required to be cleared each year so that after 5 years, 500 metres would be free of white-edged nightshade plants. Three other adjoining properties had scattered infestations and were required to destroy all white-edged nightshade plants each year.

The primary failing of the former programme was the core property was not, and is still not, farmed intensively. The re-generating scrub was growing faster than the white-edged nightshade. Inspecting the 100 to 500 metres became virtually impossible. The regenerating scrub has reduced the density of the infestation on the core property substantially.

Since that time, a successful annual compliance programme has been implemented. The core property boundary is being kept clear and there is a continued decline in the level of infestations on the three neighbouring properties.

Current situation in 2017 There is one large geographical area in the Beatrix Bay area of the Pelorus Sound that has the majority of the white-edged nightshade infestation. The overall infestation is almost entirely confined to a single property. Three adjoining properties have relatively low level infestations, most likely as a result of bird or feral pig dispersed seed.

The existing programme has seen the status quo remain. Infestations of white-edged nightshade on the three properties surrounding the core property are being managed effectively (through vigilant occupier control effort). Physical spread is also being minimised through the boundary control system for the land that falls inside the core property.

Options to respond to white-edged nightshade Baseline: No RPMP In this scenario no active management of white-edged nightshade is undertaken. While some voluntary control would occur, it is assumed the plant would not be contained.




Level of analysis for white-edged nightshade Council has determined that a low level of analysis be undertaken for white-edged nightshade. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.


259

Impacts White-edged nightshade is a large shrub or tree with aggressive spines. It originates from North Africa. It will grow up to 3 metres high and will form dense thickets, which become impenetrable and displace preferred pasture species. It will also displace native species.


Economic Diminished pasture and livestock production

Control of white-edged nightshade will prevent damage to 265,000 hectares of pastoral habitat. It is estimated that white-edged nightshade will infest pastoral and tussock land covers, including 10% of intensive pastoral land uses (LUC classes I, II and III) and up to 30% of all hill/high country pastoral land uses (LUC Classes IV, V, and VI ). Modelling of this scenario assumed spread characteristics of between 10 and 50 metres, and new sites are established annually from spread through machinery, hay etc71, and the plant takes between 15 and 40 years to reach its maximum density at a site in an uncontrolled situation.








Regional community



71 This approximately reflects the rate of establishment of sites since its introduction. The number of new sites established are proportional to the current area displaced by the plant - at current displacement one new site is established annually.


260


Benefit Option


The prevention of white-edged nightshade building in density or infesting new areas and the resulting impact of that on pastoral productivity.




Programme Costs

Option


GST)


GST)


GST)


- $18,000 $16,500

Land occupier costs - $250,000+ $25,000

Total - $268,000+ $41,500


over time


Proposed allocation of costs It is proposed that the majority of the programme costs are allocated to occupiers of land that have white-edged nightshade infestations. This has been done by way of rules requiring the occupiers to manage white-edged nightshade.





261


Level of Risk

Option


N/A High Low

Reason The property that harbours the historically entrenched infestation is heavily vegetated. Implementing effective control measures across all infested properties would be technically very difficult, nearing impossible.

White-edged nightshade occurs on three properties adjoining the Containment Area. Being able to effectively manage the infestations on these properties is much lower risk.




262

7.39 Wilding conifers Definition Wilding conifers are any introduced conifer tree, including (but not limited to) any of the species listed in Table 13, established by natural means, unless it is located within a forest plantation, and does not create any greater risk or wilding conifer spread to adjacent or nearby land than the forest plantation that it is part of.

For the purposes of this definition, a forest plantation is an area of 1 hectare or more of predominantly planted trees.

Table 13: Species for the purposes of the wilding conifers definition

Common Name Scientific Name

Douglas fir Pseudotsuga menziesii

Lodgepole or contorta pine* Pinus contorta

Scots pine* Pinus sylvestris

Mountain pine* Pinus.mugo (including sub-species and botanical variants)

Bishops pine Pinus muricata

Maritime pine Pinus pinaster

Ponderosa pine Pinus ponderosa

Corsican pine* Pinus nigra

European larch* Larix decidua

Radiata pine Pinus radiata

Western white pine* Pinus monticola

Mexican weeping pine Pinus patula *These species also have specific programmes - see relevant RPMP section.

Why are they a threat? Wilding conifers can have significant impacts on native ecosystems, particularly those low in stature such as tussock and indigenous grasslands, alpine ecosystems and subalpine scrub. Wilding conifers grow faster and taller than low-stature vegetation so can easily out-compete these species. Soil and soil fauna are also altered when wilding conifers replace native ecosystems.

Wilding conifers can also adversely affect amenity and landscape values. These landscapes are important for tourism and large scale landscape changes can impact on the value gained from tourism in Marlborough.



In areas of extensive pastoral farming, wilding conifer infestations adversely impact economic wellbeing by reducing available grazing and limiting the options for future land use.


263

Reasons for proposing a Plan In Marlborough, it is recognised the first up task of managing wilding conifers to sustainable levels is one best carried out through large scale collaborative programmes outside of the Plan. However, to ensure the achievements gained by investing in management (by a number of parties), a programme within a Plan can ensure the gains made are sustainable in the long term. As such, the proposed programme reflects this.

Why the Plan is more appropriate than relying on voluntary actions In essence, the previously mentioned collaborative wilding conifer management projects are voluntary actions. Interested parties, including the Council, the Department of Conservation, the Ministry for Primary Industries (MPI), Land Information New Zealand, the community at large and other organisations recognise the importance of managing wilding conifers. This culminated in the development of the New Zealand Wilding Conifer Management Strategy (2015) then subsequent Crown Funding administered by MPI to invest in the issue (the National Wilding Conifer Management Programme). Prior to this, local trusts such as the Marlborough Sounds Restoration Trust and South Marlborough Landscape Restoration Trust established through a community desire to take action for community good.

All of these aspects to wilding conifer management as occurring under the banner of voluntary action.

However, management of wilding conifers is a long game. Under all of the scenarios of intervention, there is a concern that up-front investment could be put at risk by a lack of voluntary actions being undertaken at an individual land occupier level. As such, it is proposed that this Plan acknowledges the success of voluntary action in one respect (the broad collaborative management approaches), but the Plan is more appropriate to address the long term sustainability of achievements made.

7.39.1 Objective Over the duration of this Plan, ensure the ongoing control of wilding conifers on land within the Marlborough region that has been subject to a Collaborative Wilding Conifer Programme in order to minimise adverse effects on the environment, enjoyment of the natural environment and economic wellbeing.




Principle measures to achieve the objective 1) Collaborative Progammes












264




Council may:






7.39.2 Rules Rule 7.39.2.1 Occupiers of land within a Collaborative Wilding Conifer Programme Area (see Map 11), upon written notification that the programme has ceased and/or met the objectives, shall destroy all wilding conifers present on their land prior to cone bearing.


Note 1: If in place, Collaborative Wilding Conifer Programme Areas, for the purposes of this rule, are able to be viewed online via Council’s Smart Maps service.

Note 2: For clarity, the process relating to the instigation of a Collaborative Wilding Programme Area, and notification of occupiers when the programme ceases and/or has met the objectives, can be found in Appendix 1.

Explanation of the rule: The purpose of Rule 7.39.2.1 is in accordance with section 73(5)(h) in that occupiers of land within areas that have been subject to a Collaborative Wilding Conifer Programme are required to take specified actions to prevent the pest re-establishing on that land.


7.39.2 Analysis of the benefits and costs for wilding conifers Background Wilding conifers are sourced from various parent trees planted for various reasons across most of Marlborough. In the highly prone areas of Marlborough, that being South Marlborough, species were planted during the era of soil conservation efforts. As these trees thrived and subsequently matured, they gave rise to a wave of wilding progeny spreading prolifically out onto surrounding land. Seed from wilding conifers that grow and reach cone bearing age can be blown long distances during high wind events and the cycle begins again.

Current situation in 2017 Wilding conifers can be observed across most of the Marlborough district. However, the impact (current or potential) and further spread propensity varies greatly. As a result, there is often prioritisation


265

Map 11: Molesworth Wilding Conifer Collaborative Area


266

Baseline: No RPMP In this scenario, no control of wilding conifers is undertaken at all, and the assumption is made that wilding conifers continues to establish in new areas and no attempt is made to control original infestations.

Control option(s): 1. Progressive Containment Programme: in which the intermediate outcome for the programme



Level of analysis for wilding conifers Council has determined that a low level of analysis be undertaken for wilding conifers. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.

Impacts Identify impact Quantify impact Environmental Wilding conifers grows faster and taller than low-stature indigenous vegetation. Indigenous ecosystems that are at particular risk of invasion include: tussock and other indigenous grasslands; alpine ecosystems; subalpine, dryland and other scrub and shrublands; wetlands; turf communities and coastal margins, cliffs and bluffs. Once they have invaded, trees can shade out many native plant communities and can also change soil characteristics72.






267

Water Quantity Where there are significant changes to land cover within a catchment, such as a domination of wilding conifers, surfaces water flows can be negatively affected. This is more pronounced in dry South Island catchments.


Economic Once wilding conifers spread onto extensive or marginal farmland, active control required may be difficult for the land owner/occupier to justify financially given the marginal worth of the land for grazing. This can result in a compounding reduction on land area available for extensive grazing.









Regional community



73 Duncan MJ 1996. A methodology for identification of areas vulnerable to flow reductions because of afforestation. NIWA Christchurch Consultancy Report No CRC60512. Cited in Environment Canterbury Regional Council 2011. Christchurch. 74 Environment Canterbury Regional Council 2011. Canterbury Natural Resources Regional Plan.Chapter 5: water quantity. http://ecan.govt.nz/publications/Plans/nrrp-chapter-5-cover- main-text-operative-110611.pdf , Environment Canterbury RegionalCouncil. 214 p. 75 https://lris.scinfo.org.nz/layer/412/SourceLCDB v4.0 Landcare Research Creative Commons Attrribution 3.0 New Zealand. Accessed 7 August 2017.



268


Benefit Option

No RPMP Progressive Containment Sustained Control The prevention of wilding conifers re-establishing and the resulting impact of that on environmental values.



The prevention of wilding conifers re-establishing and the resulting impact of that on landscape values.

The prevention of wilding conifers re-establishing and the resulting impact of that on catchment water yields.

The prevention of wilding conifers re-establishing and the resulting impact of that on production values of pastoral land.


269



No RPMP


Sustained Control


-

$20,000 $500


$100,000+




Low, but increases








270


Level of Risk

Option



Reason The effective management of wilding conifers to a progressive containment objective within a RPMP programme would set a level of expectation that effective management was to occur. As a result, there is a real risk of political and/or public concern over cost that would adversely affect the implementation of the programme.



Most preferred option Sustained Control Programme (with the active management to occur outside of the RPMP under Collaborative Wilding Conifer Programmes, detailed within the Operational Plan.)


271

7.40 Willow-leaved hakea (Hakea salicifolia) Why is it a threat? First recorded in New Zealand in 1908, willow-leaved hakea is a large, erect shrub or small tree <5 metres high and not prickly. A leathery, flattened and willow-like leaf have either little or no stem and has woody oval fruits, with curved beak, that release winged seeds. It is an aggressive and fast growing plant and originating from Eastern Australia, particular well adapted to colonise after fire.

It forms extensive stands in shrublands, displacing native vegetation.

Reasons for proposing a Plan While willow-leaved hakea has naturalised in Marlborough, only a discrete infestation occurs on Rangitoto ki te Tonga/D’Urville Island. Due to the nature of the ultramafic geology on Rangitoto ki te Tonga/D’Urville Island, and subsequent ecosystems, there is a particular threat of the infestation spreading and taking a hold into the future. Adequate control tools are available are available to implement a control programme.

Why the Plan is more appropriate than relying on voluntary actions With such a discrete infestation, the management of this species needs to be both strategic and intensive. Because of this, it is more appropriate to be management through a structured programme of delivery enabled by a Plan rather than relying on voluntary actions.

7.40.1 Objective 7.40.1.1 By 2035, willow-leaved hakea (Hakea salicifolia) on Rangitoto ki te Tonga/D’Urville Island

(see Map 12) will have been controlled to zero levels, where no plants are found over the preceding 5 years, to prevent adverse effects on the environment, and enjoyment of the natural environment.

7.40.1.2 By the end of the term of this Plan, willow-leaved hakea (Hakea salicifolia) on Rangitoto ki te Tonga/D’Urville Island will have been controlled to less than 10% of the original infestation size at the commencement of management based on plant numbers, to prevent adverse effects on the environment, and enjoyment of the natural environment.






a) Delivering a service to control willow-leaved hakea in liaison with occupiers.









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Council, in conjunction with the Marlborough Sounds Restoration Trust may:






7.40.2 Rules Rule 7.40.2.1 Occupiers on Rangitoto ki te Tonga/D’Urville Island are required to notify Council of any new infestation of willow-leaved hakea (Solanum mauritianum) on land that they occupy within 5 working days of the initial observation.












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Map 12: Willow-leaved hakea programme coverage


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7.40.3 Analysis of the benefits and costs for willow-leaved hakea

Background Willow-leaved hakea (Hakea salicifolia) originates from eastern Australia and was introduced into New Zealand in 1908 for hedge and ornamental plantings.

It is recognised as an environmental weed in the Department of Conservation’s Consolidated List of Environmental Weeds in New Zealand (2008), and is subject to control in a number of areas of New Zealand, particularly around Auckland and Northland. It has also established outside its natural range in Australia, South Africa, Spain, Portugal and the United States, where it is variously recognised as a potential or actual environmental weed.

In New Zealand, willow-leaved hakea forms a small tree that can be compared to kanuka in its size and structure, but which has a tolerance for very poor soils. Where it occurs on fertile soils, it is likely to be replaced by native broadleaf species in 50-60 years. However, on infertile soils, it is likely to persist for a longer period and possibly indefinitely. It is regarded as an ecological threat where it occurs in such situations, most notably on the bare granite ridges of Abel Tasman National Park and the gumlands of Northland77.

Current situation in 2017 A stand of willow-leaved hakea has established on the eastern faces of Rangitoto ki te Tonga/D’Urville Island, near Kapowai, where it occupies infertile soils bordering the ultramafic and mafic geology of the island’s mineral belt. The core infestation on the island covers about 4 hectares. There is another 20 hectares on which occasional willow-leaved hakea occur as spread from the core stand. The affected area is all on private land.

Baseline: No RPMP In this scenario no control of willow-leaved hakea is undertaken, and the assumption is made that the plant becomes well-established and progresses toward full naturalisation in all susceptible areas in the long term.




Level of analysis for willow-leaved hakea Council has determined that a low level of analysis be undertaken for willow-leaved hakea. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.

77 McAlister, A. 2013. Research Brief: Assessing two methods for the control of willow-leaved hakea on D’Urville Island.


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Environmental The soils derived from ultramafic geology on Rangitoto ki te Tonga/D’Urville Island contain high concentrations of heavy metals such as magnesium, iron nickel and copper, which have resulted in a number of nationally rare plant species and communities establishing in these areas. These plant communities are of national significance because of their very limited distribution throughout New Zealand. Willow-leaved hakea, through its ability to colonise such environments, can alter these ecosystems significantly.

There are large areas of unaffected vegetation on Rangitoto ki te Tonga/D’Urville Island where willow-leaved hakea could colonise. In particular, the ultramfic zone is an irregular strip that runs through areas of the island making it difficult to map and/or quantify.








Regional community




Benefit Option


The prevention of willow-leaved hakea building in density, infesting new areas and the resulting impact of that on environmental values.




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Programme Costs

Option


GST)


GST)


GST)


- $51,000 $20,000


Total - $51,000 $20,000


over time






Level of Risk

Option


N/A Medium Low

Reason Control methodologies to effectively remove willow-leaved hakea from an area indefinitely are still being refined. This is a new programme and also relatively new to the occupiers affected. The operational delivery may affect occupiers and how they are currently managing their property.



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7.41 Woolly nightshade (Solanum mauritianum) Why is it a threat? First recorded in New Zealand in 1883, woolly nightshade is an invasive lowland shrub that can grow to trees 8-10 metres high and is now widely established in northern parts of the New Zealand. It is an aggressive and fast growing plant; each plant can live for 20 years. Once established, it can form dense, exclusive colonies, crowding out other plants and preventing native plant regeneration. The dust from the leaves and stems can irritate the skin, eyes, nose and throat. Each plant can produce thousands of seeds which are dispersed by birds that eat the berries. It reproduces very quickly in that seedlings germinated in summer are able to flower and produce seeds by autumn.

Reasons for proposing a Plan Woolly nightshade is still within the very early stages of naturalisation in Marlborough. Adequate control tools are available are available to implement a control programme to place this species under management.

Why the Plan is more appropriate than relying on voluntary actions With so few known sites, the management of this species needs to be both strategic and intensive. Because of this, it is more appropriate to be management through a structured programme of delivery enabled by a Plan rather than relying on voluntary actions.

7.41.1 Objective Over the duration of the Plan, control woolly nightshade (Solanum mauritianum) in the Marlborough district by maintaining or reducing the number of plants found in known areas to minimise adverse effects on economic wellbeing, the environment and enjoyment of the natural environment.




Principle measures to achieve the objective 1. Council Inspection and Service Delivery


a) Delivering a service to control woolly nightshade in liaison with the occupier.




2. Requirement to Act





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3. Advocacy and Education

Council may:






7.41.2 Rules Rule 7.40.2.1 Occupiers are required to notify Council of any new infestation of woolly nightshade (Solanum mauritianum) on land that they occupy within 5 working days of the initial observation.











7.41.3 Analysis of the benefits and costs for woolly nightshade

Background For a number of years, there have only been two known properties that contain a limited infestation of woolly nightshade in Marlborough. These two properties adjoin each other in a remote area of Port Hardy, Rangitoto ki te Tonga/D’Urville Island. In 2014, another isolated infestation was found in Moetapu Bay on a property and the adjoining road reserve.

Over this time, much time has been spent determining whether active management should occur for the infestation located on Rangitoto ki te Tonga/D’Urville Island. The new infestation at Moetapu Bay has been placed under management and surveillance given the isolated nature of it.


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Current situation in 2017 There are a total of four known properties where woolly nightshade is known to exist in Marlborough. The mapped extent of occupancy totals 16 hectares, with only anecdotal information regarding the type and density of the infestations.

One of the biggest obstacles to intervention to date has been the design and potential cost of a programme for the Rangitoto ki te Tonga/D’Urville Island infestation. The analysis below outlines a case to proceed with intervention, at comparably large cost, given the future impact potential on, primarily Rangitoto ki te Tonga/D’Urville Island, and also mainland areas of Marlborough.

Options to respond to woolly nightshade Baseline: No RPMP In this scenario no control of woolly nightshade is undertaken, and the assumption is made that the plant becomes well-established and progresses toward full naturalisation in all susceptible areas in the long term.




Level of analysis for woolly nightshade Council has determined that a low level of analysis be undertaken for woolly nightshade. The justification for this decision is documented in the supporting information document to this Proposal. That document also contains information about the risks that the objectives will not be reached.


Environmental Plants grow and mature rapidly, forming dense stands. These stands have an allelopathic affect (produces toxins that inhibit regeneration of other vegetation).

Approximately 400,000 hectares of the Marlborough district is at risk for infestation of woolly nightshade. Coupled with this is the fact that due to the geography of the district, there is 1800 kilometres of coastline where there is often no frost. Frost is a key determining factor over the ability of woolly nightshade to establish. It is these coastlines that often hold high aesthetic and ecological values and also has poor accessibility for control78. In particular, the current key infestation on Rangitoto ki te Tonga/D’Urville Island is in close proximity to both Stephens Island and the mineral belt ecosystems on the island itself. The impact on the mineral belt may be slightly lower than anticipated due the ‘frosting affect’ and potentially the low fertility inhibiting growth.

Economic Impact on production forestry through competition for light and space and/or extensively managed pastoral areas for the same reasons.

78 Kaitiaki O Ngahere. 2017. Impact and Threat Analysis for Solanum mauritianum. Report prepared for Marlboroguh District Council.


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Regional community




Benefit Option


The prevention of woolly nightshade building in density, infesting new areas and the resulting impact of that on environmental values.




Programme Costs

Option


GST)


GST)


GST)


- $150,000+ $51,000


Total - $150,000+ $51,000


over time




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Level of Risk

Option


N/A High Low/Medium

Reason Control methodologies to effectively remove woolly nightshade from an area indefinitely are still being refined. This is a new programme and also relatively new to the occupiers affected. The operational delivery may affect occupiers and how they are currently managing their property.





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8. Monitoring 8.1 Measuring against programme objectives Each proposed programme contains one or more programme objectives. It is progress against these objectives that provide the key measures of success of the Plan implementation.

Each year within the report on the Operational Plan, progress against each of the programme objective(s) will be outlined and reported upon.

The way in which each programme is monitored varies depending on the biological nature of the organism, the nature of infestations and also the cost effectiveness of the method of monitoring relative to the programme cost. A summary of the programme monitoring methods is outlined below in Table 14.

Table 14: Programme monitoring methods summary

Common Name Monitoring method Frequency

African feather grass Outputs as a proxy for population

Annually during operations

Bathurst bur

Boneseed

Broom Outputs as a proxy for population


Brushtail possum Detections/Reports Summarised annually

Bur daisy Outputs as a proxy for population


Cathedral bells

Chilean needle grass Population assessments Annually

Chinese pennisetum Outputs as a proxy for population


Climbing spindleberry

Contorta pine Status summary Annually

Cotton thistle Outputs as a proxy for population


Corsican pine Status summary Annually

Eel grass Outputs as a proxy for population


European larch (excluding sterile hybrids)

Status summary Annually

Evergreen buckthorn Outputs as a proxy for population


Giant needle grass

Gorse

Kangaroo grass

Madeira vine or mignonette vine

Mediterranean fanworm

Moth plant

Mountain pine (including all sub-species and botanical variants)

Status summary Annually

Nassella tussock Population assessments Annually


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Common Name Monitoring method Frequency

Parrots feather Outputs as a proxy for population


Purple loosestrife Outputs as a proxy for population


Rabbits Population assessments Annually

Reed sweet grass Outputs as a proxy for population


Rooks Detections/Reports Summarised annually

Rough horsetail Outputs as a proxy for population


Saffron thistle

Scots pine Status summary Annually

Senegal tea Outputs as a proxy for population


Spartina

Tall wheat grass

Wallabies Detections/Reports Summarised annually

Western white pine Status summary Annually

White-edged nightshade Outputs as a proxy for population


Wilding conifers Status summary Annually

Willow-leaved hakea Outputs as a proxy for population


Woolly nightshade

8.2 Monitoring the management agency’s performance As the management agency responsible for implementing the Plan, Council will:

(a) prepare an Operational Plan within three months of the Plan being approved;

(b) report on the Operational Plan, review the Operational Plan and amend the Operational Plan if needed within five months after the end of each financial year.

Financial reporting and performance will be outlined within the Annual Plan Report produced by Council each year in accordance with the Local Government Act 2002.

A combination of the annual report on the Operational Plan and the Annual Plan Report will provide a comprehensive summary of the management agency’s performance.

9. Exemptions Any occupier or other person may write to Council to seek an exemption from any provision of a rule set out in Part Two of the Plan. However, a rule may state that no exemptions will be considered, or it may limit the circumstances to which exemptions apply (e.g. scientific purposes).

The requirements in section 78 of the Act must be met for a person to be granted an exemption. This includes an obligation by Council to keep and maintain a register that records the number and nature of exemptions granted. This register will be made available during normal business hours or on a website maintained by Council.


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The process followed for an application for an exemption is outlined below.

Written application received by Council

Assessment of application against the criteria outlined within section 78 of the

Act

Application granted without conditions

Application granted withconditions Council

considers appropriate, within the bounds of

section 78

Application not granted

Applicant notified of unsuccessful application. Obligation within relevant

Rule remains

Applicant notified of successful application.

Rule obligation no longer applies

Applicant notified of successful application. Obligations are now in accordance with the exemption conditions


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Part Three Administrative provisions

10. Powers conferred 10.1 Powers of Authorised Persons under Part 6 of the Act The Principal Officer (Chief Executive) of Marlborough District Council may appoint authorised persons to exercise the functions, powers and duties under the Act in accordance with section 103 of the Act.

Where necessary, Authorised Persons will use those statutory powers of Part 6 of the Act, as shown in Table 15, to implement this Plan.

Table 15: Powers from under Part 6 to be used

Administrative Provisions Biosecurity Act Reference

The appointment of authorised and accredited persons Sections 103(3) and (7)

Delegation to authorised persons Section 105

Power to require assistance Section 106

Power of inspections and duties Sections 109, 110 and 112

Power to record information Section 113

General powers Sections 114 and 114A

Use of dogs and devices Section 115

Power to intercept risk goods Section 120

Power to examine organisms Section 121

Power to give directions Section 122

Power to act on default Section 128

Liens Section 129

Declaration of restricted areas Section 130

Declaration of controlled areas Section 131

Options for cost recovery Section 135

Failure to pay Section 136

10.2 Powers under other sections of the Act A Chief Technical Officer (employed under the State Sector Act 1988) may appoint authorised people to implement other biosecurity law considered necessary. One example is where restrictions on selling, propagating and distributing pests (under sections 52 and 53 of the Act) must be enforced. Another example is where owners and/or occupiers are asked for information (under section 43 of the Act).

11. Funding 11.1 Introduction The Act requires that funding is thoroughly examined. For a Proposal, this includes:

• analysing the costs and benefits of the plan and any reasonable alternative measures;

• noting how much any person will likely benefit from the plan;


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• noting how any person’s actions or inactions may contribute to creating, continuing or making worse the problems that the plan proposes to resolve;

• noting the reason for allocating costs; and

• noting whether any unusual administrative problems or costs are expected in recovering the costs from any person who is required to pay.

11.2 Beneficiaries and exacerbators The assessment of beneficiaries and exacerbators as used in this Proposal and resulting cost allocation analysis is outlined in Table 16.

Table 16: Assessment of beneficiaries and exacerbators







Regional community Occupiers of land with the pest present


Each proposed programme falls within one of these groupings and this highlighted within each respective proposed programme section.

The single exception is the proposed programme for Mediterranean fanworm. This programme does not occur on rateable land. As such, a more detailed cost allocation breakdown has been developed that covers the wider programme cost and is outlined specifically within the proposed programme section.

11.3 Funding sources and reasons for funding Sources Funding for the implementation of the proposed Plan is sourced through three distinct avenues:

1. By placing an obligation, and resulting cost, on occupiers (of land or vessels) through Plan rules;

2. Directly collecting funds from ratepayers within the region via the Local Government (Rating) Act 2002 to cover Council costs identified within the Proposal;

3. Other direct funding sources; for example, Crown contributions or direct actions toward the programme implementation.

The Council costs for implementing the Plan are proposed to be funded through general rates collected under the Local Government (Rating) Act 2002. In making this decision, Council is given regard to section 100T of the Act (see Table 17).


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Table 17: Assessment against section 100T of the Act for the use of rates

Provisions within section 100T of the Biosecurity Act 1993

Assessment

The extent to which the Plan relates to the interests of the occupiers of the properties on which the rate would be levied.

The costs allocation model outlined below has given regard to all relevant sub-sections of section 100T of the Biosecurity Act 1993. This has been through the use of differing weightings across the rating districts that have regard to: • the nature of the land; • direct and indirect benefits; • the presence or prevalence of the proposed

pests; and/or • the collective benefits to ratepayers from the

implementation of the Plan.

The extent to which the occupiers of the properties on which the rate would be levied will obtain direct or indirect benefits from the implementation on the Plan.

The collective benefits of the implementation of the Plan to the occupiers of the properties on which the rate would be levied compared with the collective costs to then of the rate.

The extent to which the characteristics of the properties on which the rate would be levied and the uses to which they are put contribute to the presence or prevalence of the pest or pests covered by the Plan.

Allocation model for Council costs An allocation model is proposed in order to allocate Council costs across the rating districts used in Marlborough for the collection of general rates. This model uses the same four groupings of beneficiaries and exacerbators outlined in section 11.2 and also the nature and location of all proposed programmes.

The final Council cost for the implementation of the Plan is then allocated across the rating districts in accordance with the calculations used to allocate rates in accordance with the Local Government (Rating) Act 2002.


289

Table 18: Breakdown of weightings used for the collection of rates under the Local Government (Rating) Act 2002.

0 = no benefit received, 100 = full benefit received.

NOTE – this allocation model is subject to the 2018 Council Long Term Plan process.

Weightings used for calculation

Grouping

Rating Districts

Blenheim Residential

Blenheim Commercial

Blenheim Vicinity

Blenheim Vicinity

Commercial

Picton Residential

1 60 60 60 60 60

2 10 10 50 50 10

3 25 25 45 45 25

4 100 100 100 100 100

Grouping

Rating Districts

Picton Commercial

Picton Vicinity Picton Vicinity Commercial

Rural Residential

Rural Commercial

1 60 60 60 100 100

2 10 10 10 100 100

3 25 45 45 100 100

4 100 100 100 100 100

Grouping

Rating Districts

Sounds Residential

Sounds Commercial

1 80 80

2 30 30

3 45 45

4 100 100

Final weightings proposed to be used for rate allocation (using weighted average model - see Council LTP/Annual Plan Rate Allocation summary) Rating Districts

Blenheim Residential Blenheim Commercial

Blenheim Vicinity Blenheim Vicinity Commercial

Picton Residential

32 32 61 61 32

Rating Districts

Picton Commercial Picton Vicinity Picton Vicinity Commercial

Rural Residential Rural Commercial

32 34 34 100 100

Rating Districts

Sounds Residential Sounds Commercial

48 48


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Explanatory notes for weightings It needs to be noted that this Local Government Act weighting model is predominantly designed to assess the benefit received by ratepayers they attract to their own property being rated. However, the assessment of beneficiaries under the Biosecurity Act 1993, and this Proposal, is broader. It includes the benefit that is attributed to a combination of both the property and the ratepayer as a person living in Marlborough. This is seen in the weightings for groupings that have a predominantly environmental benefit in that all ratepayers benefit for a healthy, functioning environment and as such the weighting has been attributed across all rating districts.

The basis for this spread of weightings for Council costs is as follows:

Grouping 1 Proposed programmes within this grouping include wallabies and the RPMP programme for wilding conifers.

These programmes have very broad benefit across the regional community. Wallabies have the potential to severely degrade natural areas via direct browsing. The benefit is generated from preventing multiple species establishing in Marlborough. The main risks are from Bennett’s wallaby establishing in the scrub and open environment of South Marlborough and Dama wallaby that would thrive through the scrub and forested environments of the Marlborough Sounds.

If left unmanaged, wilding conifers have the potential to severely alter landscapes and also impact on catchment water yields. The proposed costs for the wilding conifers programme (plus the high spread risk species) are low. However, there are substantial Council costs associated with wilding conifer management that sit within non-regulatory collaborative programmes projects. The weightings and cost allocation used for those costs (and detailed via Local Government Act financial processes) are the same as that outlined for Grouping 1.

There is no clear mechanism available to allocate cost of the programme to exacerbators.

These factors result in the maximum benefit attributed to the Rural rating districts, and near maximum for the Sounds rating district. The impact that both these programmes would have on the natural environment, and enjoyment of the natural environment, results in a relatively high and even benefit weighing across the remainder of the rating districts.

Grouping 2 Proposed programmes within this grouping include that for broom, Chilean needle grass, gorse, kangaroo grass, rabbits and white-edged nightshade.

It is this grouping that sees Rural occupiers as both the major beneficiary and also the major exacerbator. As such, due to the established natures of these species, the key cost allocation method is an obligation of occupiers with the pest to be responsible for its management.

For some programmes, such as Chilean needle grass and kangaroo grass, Council costs include more than just compliance activities. In order to achieve the programme objective, active intervention by Council is needed.

The Council cost weightings used see the Rural rating districts attributed with the maximum benefit weighting, with a much lower weighting across other rating districts.

Grouping 3 Proposed programmes within this grouping include that for African feather grass, Bathurst bur, bur daisy, Chinese pennisetum, cotton thistle, giant needle grass, reed sweet grass, rooks, saffron thistle and tall wheat grass.

This cost allocation principles with this grouping is very similar to that that of Grouping 2. However, the proposed programmes for these species carry a greater degree of environmental benefit due to both the nature of the species and the potential invasion risk.


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The other key difference to Grouping 2 is that it is proposed for all of the programme costs for these species to be borne by Council given the implementation will be solely through service delivery.

The Council cost weightings used see the Rural rating districts attributed with the maximum benefit weighting but an increased weighting for other rating districts in recognition of the increased environmental benefit.

Grouping 4 All of the remaining proposed programmes are within a grouping where there are no clear beneficiaries or exacerbators other than the regional community at large. All of the proposed programme costs relate to Council service delivery and the species all threaten the integrity of natural ecosystems.

The Council cost weighting uses attributes evenly weighted across all rating districts.

11.4 Anticipated costs of implementing the Plan Given costs of implementing the proposed Plan fall in numerous areas, and by quantum, mostly outside Council, Table 19 provides a summary of the anticipated costs of implementation the proposed Plan.

Table 19: Anticipated costs - by group (excl GST)

Group Associated proposed Plan programme

Vessel owners that

enter Marlborough

waters (estimated)

Occupiers subject to

rule obligations to control

pests (estimated)

MPI DOC Marlborough District Council

Total

Mediterranean fanworm $390,515 $28,000 $135,000 $553,515

Broom, Chilean needle grass, gorse, kangaroo grass, nassella tussock, rabbits, white-edged nightshade

$2,139,925 $762,500 $2,902,425

Boneseed, cathedral bells, climbing spindleberry, evergreen buckthorn, madeira vine, spartina

$75,200 $70,850 $146,050

All remaining programmes $274,412 $274,412

Total $390,515 $2,139,925 $28,000 $75,200 $1,242,762 $3,882,402 Proportion of total anticipated cost

10% 55% 1% 2% 32%


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Table 20: Summary of Council cost allocation across rating districts.

Note: These figures are subject to the 2018 Council Long Term Plan process

• Note - Includes non-RPMP project/programme costs (guided by Biosecurity Strategy) totalling $445,360 incl GST. These will be outlined within a combined Operational Plan.

RATE FUNDING

(incl. GST)

Residual Rate-Req General Rates

1171-Blenheim Residential Rate

1172-Blenheim Commercial Rate

1191-Blenheim-Vic Residential Rate

1192-Blenheim-Vic Commercial Rate

1211- Picton Residential Rate

1212- Picton Commercial Rate

1231- Picton-Vic Residential Rate

1232- Picton-Vic Commercial Rate

1251- Rural Residential Rate

1252- Rural Commercial Rate

1271-Sounds Residential Rate

1272-Sounds Commercial Rate

2017/18 Financial Year

“CURRENT”

(for comparison)

Weighting

13.00

13.00

38.00

38.00

13.00 13.00

38.00 38.00

100.00

100.00

15.00

15.00

Resultant cents per $ / rate per capita

$ 0.005069

$ 0.005069

$ 0.014816

$ 0.014816

$ 0.005069 $ 0.005069

$ 0.014816 $ 0.014816

$ 0.038991

$ 0.038991

$ 0.005849

$ 0.005849

Resultant benefit allocation [%TotRates]

6.04% 1.17% 22.06% 0.62% 1.13% 0.28% 1.63% 0.05% 64.53% 0.94% 1.51% 0.04%

Resultant allocation $ 1,400,196

$ 84,580

$ 16,443

$ 308,902

$ 8,657

$ 15,790 $ 3,912

$ 22,802 $ 757

$ 903,591

$ 13,183

$ 21,086

$ 494

2018/19 onward “PROPOSED”

Proposed new weighting

32.00

32.00

61.00

61.00

32.00 32.00

34.00 34.00

100.00

100.00

48.00

48.00

Resultant cents per $ / rate per capita

$ 0.013222

$ 0.013222

$ 0.025204

$ 0.025204

$ 0.013222 $ 0.013222

$ 0.014048 $ 0.014048

$ 0.041319

$ 0.041319

$ 0.019833

$ 0.019833

Resultant benefit allocation [%TotRates]

11.48% 2.23% 27.34% 0.77% 2.14% 0.53% 1.12% 0.04% 49.82% 0.73% 3.72% 0.09%

Resultant allocation $ 1,922,150

$ 220,628

$ 42,891

$ 525,478

$ 14,727

$ 41,187 $ 10,204

$ 21,620 $ 717

$ 957,547

$ 13,970

$ 71,504

$ 1,677

Difference

$ 136,049

$ 26,449

$ 216,576

$ 6,070

$ 25,398 $ 6,292 -$ 1,182 -$ 39

$ 53,956

$ 787

$ 50,418

$ 1,182


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Glossary

Act means the Biosecurity Act 1993 (including any amendments).

Appropriate means as determined to be appropriate by the Council or their officers acting under delegated authority.

Authorised Person means a person appointed as an authorised person under section 103 of the Act.

Beneficiary means the receiver of benefits accruing from the implementation of the Plan.

Biological Control means the introduction or establishment of living organisms which will prey on or adversely affect another organism.

Chief Technical Officer means a person appointed a Chief Technical Officer under section 101 of the Act.

Council means the Marlborough District Council.

Crown Land means land vested in Her Majesty and administered by a Minister for the time being charged with the administration of the Department of State that has control of the land; and includes all and for the time being forming part of any National Park, any reserve within the meaning of the Reserves Act 1977 and all unoccupied lands of the Crown.

Craft the same meaning as that within the Biosecurity Act 1993.

Department+ the same meaning as in the State Sector Act 1988.

Destroy means pull, breakdown, demolish, make useless, kill, cause to cease to exist.

Director-General means the Chief Executive of the Ministry.

Ecosystem means a dynamic complex of plant, animal and micro-organism communities and their non-living environment, interacting as a functional unit.

Effect unless the context otherwise requires, the term ‘effect’ includes: • any positive or adverse effects; and • any temporary or permanent effect; and • any past, present or future effect; and • any cumulative effect which arises over time or in combination with

other effects regardless of the scale, intensity, duration or frequency of the effect, and also includes: • any potential effect of high probability; and • any potential effect of low probability which has a high potential

impact.

Endemic where a pest is commonly found within a defined geographic area.

Enforce means to compel, observance with the law.


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Environment includes: (a) ecosystems and their constituent parts, including people and their

communities; and (b) all natural and physical resources; and (c) amenity values; and (d) the aesthetic, cultural, economic and social conditions that affect or

are affected by any matter referred to in paragraphs (a) to (c) of this definition.

Exacerbator means a person, who by their actions or inaction, contributes to the creation, continuance, or exacerbation of a particular pest management problem.

Local Authority means a regional council or territorial authority.

Management Agency means the department, authority or body corporate specified in a pest management plan as the management agency who is tasked with implementing the plan.

Management Plan means an agreed plan between an occupier and Council that outlines how a pest will be managed on the place they occupy. Can be used in conjunction with pest management plan rules.

Means of Achievement refers to general management options or tactics by which the management agency will achieve an objective(s).

Ministry means the Department of State that, with the authority of the Prime Minister, is for the time being responsible for the administration of the Act.

Monitor means to observe and/or measure the occurrence of a pest where it is known to occur.

Objective means a statement that outlines a specific, measurable, achievable, realistic and time-bound outcome, in accordance with the National Policy Direction for Pest Management.

Occupier the same meaning as that within the Biosecurity Act 1993.

Operational Plan plan prepared by the management agency under section 100B of the Act.

Organic material+ subject to subsection (2) of this section, means any material that is or contains: (a) material derived from an organism; or (b) an excretion or secretion of an organism (whether or not it also contains material derived from a human being or contains the secretions of a human being).

Organism the same meaning as that within the Biosecurity Act 1993.

Person the same meaning as that within the Biosecurity Act 1993.

Pest the same meaning as that within the Biosecurity Act 1993.

Pest Agent the same meaning as that within the Biosecurity Act 1993.

Pest Management Plan the same meaning as that within the Biosecurity Act 1993.

Place the same meaning as that within the Biosecurity Act 1993.

Principal Officer the same meaning as that within the Biosecurity Act 1993.


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Property the area of land as that is defined by Council used for the collection of rates under the Local Government (Rating) Act 2002. Defined by the term Property Number. In the absence of a Property Number, means the underlying computer register title.

Region in relation to a unitary authority, means the region in respect of which it has the functions, duties and powers of a regional council.

Regional Council has the same meaning as in the Local Government Act 2002 and includes the Chatham Islands Council and unitary authorities.

Regulations means regulations made under the Act.

Responsible Minister means the Minister who, under the authority of any warrant or with the authority of the Prime Minister, is for the time being responsible for the administration of this Act.

Restricted Place the same meaning as that within the Biosecurity Act 1993.

Risk Goods the same meaning as that within the Biosecurity Act 1993.

Road the same meaning as in section 315 of the Local Government Act 1974.

Rule means a rule included in a pest management plan or a pathway management plan.

Unitary Authority means territorial authority that, by virtue of section 37N (1) of the Local Government Act 1974, has the functions, duties and powers of a regional council in respect of a region under its control.

Unwanted Organism the same meaning as that within the Biosecurity Act 1993.


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Appendices

Appendix 1 Wilding conifer Collaborative Wilding Conifer Programme Areas process

Background For the purpose of discussing Collaborative Wilding Conifer Programme Areas (CWCPA), they address the management of both wilding conifers and high risk conifer species as defined in the Proposal.

As outlined within the programme for wilding conifers, and some specific species of conifer, non-regulatory CWCPA wilding conifer Collaborative Programme Areas (CPA) is referenced as a trigger mechanism for the programme rule. As a result, clarity is needed within the RPMP surrounding both how these CWCPAs CPAs are formed and, more importantly, when they cease given this is the trigger for the obligation for land occupiers begins.

Development of CWCPAs CPAs As CWCPAs CPAs are by origin non-regulatory, they are developed through a number of agencies and interested parties coming together to address the issue of wilding conifers, usually within a defined geographic area. This need to come together stems back to the strategic goals and decision making process outlined within the Marlborough District Council Biosecurity Strategy.

Given the management of wilding conifers is often a large and complex task, it is the view of Council that these collaborative programme initiatives are the most suitable method to address wilding conifer issues. However, there is often a large investment of public or third party funds into these programmes and an underlying need to ensure that investment is protected into the future.

As a result, during the development of a collaborative programme, the post-collaborative environment and transition to RPMP obligations should be taken into consideration. The criteria outlined below will be crucial to that discussion.

Transition of CWCPA CPA to RPMP obligation At a point in time, a collaborative programme will ideally reach a goal of wilding conifers/high risk species being at a level where only ongoing maintenance is required. This would be following initial control of wilding conifers within the site, and the removal of adjoining seed sources and/or the re-establishment of native forest cover sufficient to prevent on-going wilding conifer recruitment. It is at this point that those governing the programme can assess whether the collaborative programme takes ownership of the maintenance in perpetuity or cease the programme and hand over responsibility to individual occupiers. This is where RPMP obligations would be triggered. If the latter, then the following criteria must be considered:

• Within the CWCPA, or specified parts of the CWCPA, wilding conifer infestations have been managed to a level where coning trees are at zero density.

• Within the CWCPA, or specified parts of the CWCPA, other source trees that can affect the CWCPA have either been removed, management agreements reached for the long term management of those trees, and/or there has been sufficient native forest re-establishment to prevent on-going wilding conifer recruitment.

The process 1. Initial CWCPAs that are operative, understand the ability to handover responsibility, and occupiers

have been communicated with, have been identified within the Proposal for a Regional Pest Management Plan.

2. Future CWCPAs can be put forward to Council once those governing the collaborative programme understand the process, are satisfied that it meets the criteria above, and have communicated with affected land occupiers.


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3. If a new CWCPA, Council shall instigate a partial review of the RPMP to propose the inclusion of the new CWCPA and notify all affected land occupiers. Standard consultative processed shall be used in accordance with the Biosecurity Act 1993.

4. If Council decides to include the CWCPA as part of the RPMP programme, appropriate maps shall be updated to show the CWCPA within the RPMP.

5. The collaborative programme will continue to deliver on wilding conifer operations to achieve their desired outcomes with respect to wilding conifer management.

6. If those governing the collaborative programme believe they have met the desired outcomes, and meet the criteria above, they are to notify Council with a minimum of 60 days’ notice that the programme is ceasing.

7. Council will then notify all affected land occupiers that the respective rule with the RPMP will become operative from a specified date.

8. Council will then incorporate an element of surveillance/compliance across the former CWCPA area to ensure obligations are being met.

Note The community who may ultimately be subject to the obligation within the RPMP may choose to support the collaborative programme in perpetuity. As such, a notification to Council that the programme is ceasing (and triggering the obligations on occupiers) may not occur.

Council will ensure it plays a regional leadership role with respect to collaborative programmes to ensure that, although they are operating in a non-regulatory fashion, the respective goals and outcomes give effect to any respective RPMP programme objectives.


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Appendix 2 Economic analyses supporting analysis of benefits and costs

1) Chilean needle grass - No RPMP


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2) Chilean needle grass - Sustained Control


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3) Chilean needle grass - Eradication


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4) Kangaroo grass - No RPMP


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5) Kangaroo grass - Sustained Control


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6) Kangaroo grass - Eradication


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7) Mediterranean fanworm - No RPMP Note: These analyses were undertaken using regional GDP contribution data which is different to the use

of benchmarking data from the pastoral farming sector. However, the principle is the same.


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8) Mediterranean fanworm - Exclusion


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9) Nassella tussock - No RPMP


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10) Nassella tussock - Sustained Control


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Appendix 3 Modified McLean Scale for assessing rabbit populations

Scale Feral Rabbit Infestation

1 No sign seen. No feral rabbits seen.

2 Very infrequent sign seen. Unlikely to see feral rabbits.

3 Sign infrequent with faecal heaps more than 10 metres apart. Odd feral rabbit may be seen.

4 Sign frequent with some faecal heaps more than 5 metres apart, but less than 10 metres apart. Groups of feral rabbits may be seen.

5 Sign very frequent with faecal heaps less than 5 metres apart in pockets. Feral rabbits spreading.

6 Sign very frequent with faecal heaps less than 5 metres apart over the whole area. Feral rabbits may be seen over whole area.

7 Sign very frequent with 2-3 faecal heaps often less than 5 metres apart over the whole area. Feral rabbits may be seen in large numbers over the whole area.

8 Sign very frequent with 3 or more faecal heaps less than 5 metres apart over the whole area. Feral rabbits likely to be seen in large numbers over the whole area.


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Appendix 4 List of brushtail possum-free islands Island Name Location Horahora Kakahu Island Port Underwood The Brothers (North and South only) Cook Strait Moioio Island Tory Channel Mabel Island Inner Queen Charlotte Allports Island (Motuapa Island) Inner Queen Charlotte Amerikiwhati Outer Queen Charlotte Pickersgill Island East Bay Motungarara Island Outer Queen Charlotte Blumine Island Outer Queen Charlotte Kokomohua Island Outer Queen Charlotte Motuara Island Ship Cove White Rocks Cape Koamaru Clark Island Waitaria Bay Tarakaipa Island Tennyson Inlet Tawhitinui Island Tennyson Inlet Maud Island Tawhitinui Reach Duffers Reef Orchard Bay Sentinel Rock Chetwode Islands Te Kakaho (Outer Chetwode) Chetwode Islands Nukuwaiata Island (Inner Chetwode) Chetwode Islands Titi Island Guards Bay Middle Trio Trio Islands South Trio Trio Islands North Trio Trio Islands Karaka (Hamilton Island) Admiralty Bay Motuanauru Island Okiwi Bay Moukirikiri Island Okiwi Bay Otuhaereroa Island Okiwi Bay Awaiti Island Tennyson Inlet Wakaterepapanui Island Rangitoto Islands Forsyth Island Forsyth Bay Victory Island Port Hardy Puangiangi Island Rangitoto Islands Tinui Island Rangitoto Islands Tinui Island (South) Rangitoto Islands Duffers Reef (West) Orchard Bay Bird Island Forsyth Bay Stephens Island Cook Strait The Twins Outer Queen Charlotte Long Island Outer Queen Charlotte Arapaoa Island Outer Queen Charlotte Rangitoto ki te Tonga/D'Urville Island Cook Strait


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Appendix 5 Process for regional biosecurity responsesBackgroundSome Plan programmes, such as that for wallabies, rooks and brushtail possums, contain an objective to keep Marlborough free of these organisms. In the event they are detected in Marlborough, Council may need to initiate a response to address the immediate threat of establishment and/or assess the status of the population detected and decide next steps.

The following process outlines the key steps in such a response.

Detection

• Information is received by Council (or DOC for brushtail possums and/or MPI for other organisms), or detected through active surveillance, that indicates a pest may be present.

Investigation

• An investigation initiated by Council and/or DOC and/or MPI to confirm presence. • If confirmed, immediate measures may be taken to preserve options. This may take place immediately depending on the quality of the initial report.

Decision making

• The detail from the investigation and/or immediate measures will be used by decision makers to assess options going forward.

• Principles used are those detailed in the Marlborough District Council Biosecurity Strategy.• Further resources may need to be sought .

Implement decision

• The decision is implemented which may involve various management interventions.

Reveiw

• Progress is reviewed with the ability to implement adaptaptive amangement as more information comes to light.

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Regional Pest Management Plan - Marlborough · 2017. 11. 16. · Regional Pest Management Plan...

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