The property address is 3 Raines Lane, Grassington, North Yorkshire, BD23 5NJ. This is a semi-rural location within a well-established residential district on the western edge of Grassington village and within 135 metres of the River Wharfe. The site is within the boundary of the Yorkshire Dales National Park. Building: The property is a two storey detached house (built circa 1930’s) with stone cavity wall construction and hipped stone slate roof. There is an entrance porch on the front (east) elevation with hipped stone slate roof and a single storey side extension (south elevation) also with hipped stone slate roof. Bats:
A roost emergence survey was undertaken out in April 2012 (Quants Environmental Ltd). A total of 4 common pipistrelle bats emerged from beneath slates on the south-facing hipped roofs. Significantly, there were no signs of roosting bats within any part of the internal roof void.
The initial survey report (April 2012) concludes that ‘bats represent a major ecological constraint to the development proposals’. The survey recommends, ‘a second emergence survey in order to inform a Natural England EPSL application of the overall use of the property by bats during the summer roosting season’.
A subsequent emergence survey was undertaken by two surveyors in late May 2013; the survey found a total of 3 common pipistrelles emerging from within an air grid on the SE corner of the house; there was no evidence of a maternity roost, significant day roost, mating roost or place of hibernation.
Both common and soprano pipistrelle species were recorded feeding and foraging around the vicinity of the site in April 2012 and again in May 2013, however, the overall bat activity at this location was found to be relatively low frequency, despite the proximity of the relative River Wharfe.
Problem:
The impact of the proposed building extension is likely to disturb / expose low numbers of roosting bats or solitary bats or result in the temporary loss of a bat roost. YDNPA has requested that further survey work is undertaken during the optimal survey period, given the relatively early date of the initial survey (30 April) and therefore concerns that ‘a maternity roost cannot be completely ruled out’.
Solution:
A European Protected Species development licence (EPSL) is required in situations where the proposed works are likely to result in permanent loss or damage to a bat roost. A licence simply permits an action that is otherwise unlawful; conversely a licence is not required if the proposed activity is [considered] ‘unlikely to result in an offence’.
The most recent survey has found no additional evidence of significant bat roosting activity at this property and agrees with the previous assessment by Quants Environmental Ltd that the roost is ‘a non-maternity roost used only by a small number of adult male common pipistrelles’.
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This report considers the potential impact of the development can be significantly reduced by following detailed mitigation and enhancement procedures, ie. timing constraints, supervision of roof slate removal, and incorporating new roost access opportunities, thus avoiding any offences under the Habitat Regulations, thereby avoiding an EPS licence.
The Bat Mitigation Guidelines state that, “English Nature and Defra [sic. 2004] are frequently asked by consultants whether a licence is required for a particular activity. Ultimately, however, this is a decision to be made by the consultant or client”.
B introduction
B1.1 Background to activity / development
An initial scoping survey and evening emergence survey was carried out on 30 April 2013. Subsequently, the local planning authority has requested that the developer submits a second evening survey in addition to ‘definitive mitigation measures prior to determination of the application’. (Reference: email from Ian Court at YDNPA to David Baker – 21 September 2012).
(An additional survey has now been carried out – 23 May 2013)
B1.2 Full details of proposed works covered by the Method Statement.
The proposed development requires a two storey side extension on the south elevation requiring removal of an existing single storey side extension and hipped stone slate roof. A single storey side extension on the north elevation will replace an existing single storey garage.
A single storey entrance porch on the front elevation will also be removed.
The proposed extensions will require modifications to the existing main roof, verges, fascias and soffits.
C Survey and site assessment
C1.1 Pre-existing information on the bat species present at this site
An EPS survey was undertaken by Ryan Knight (Quants Environmental Ltd) on 30 April 2012. The evening emergence survey recorded 4 common pipistrelle bats emerging from the south end of the property; one bat emerged from the hipped roof over the single storey side extension and three bats emerged from 3 separate gaps beneath roof slates on the south pitch of the main house roof.
C1.2 Status of the species
Conservation status in UK: Schedule 5 of the Wildlife and Countryside Act (1981) as amended, and by the Conservation Natural Habitats etc.) Regulations (1994).
Conservation status in Europe: Appendix II of the Convention of Migratory Species.
The current status of the common pipistrelle bat (Pipistrellus pipistrellus) is ‘common and widespread throughout the UK. Long-term monitoring trends (1997 – 2012). Results of recent field surveys indicate common pipistrelle populations are increasing (reference: The state of the UK’s bats, NBMP Population trends 2012, JNCC / BCT). Within the Yorkshire Dales National Park the species’ current status is ‘common’. Although little is known about common pipistrelle winter hibernation sites, the majority of summer roosts are in buildings.
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C1.3 Objectives of the surveys
Key objectives:
(1) Determine the presence and / or absence of bats within the property and to confirm the species present at the site, the numbers of roosting bats that are likely to be present and to establish roost status.
(2) Assess the likely level of impact of the building alterations / roof disturbance on a protected species.
(3) Determine appropriate mitigation measures.
(4) Establish appropriate enhancement measures including bat-friendly design adaptations to enable low numbers of bats to continue roosting at the site.
C1.4 Scaled map / plan of site
NORTH
Figure 1: Diagrammatic plan of site – (not to scale)
C1. Description of building
The two storey detached house (built 1930’s) has a stone cavity wall construction and hipped roofs. There is a single storey side extension to the south-east elevation; this structure has a hipped stone slate roof. There is a single storey garage close to the north-west elevation. At the rear of the house is a small bay window with stone slate roof; there is also an entrance porch on the front elevation with stone slate roof.
The main roof is clad with unlined stone slates and back-pointed with lime-mortar parging.
There are several accessible roof voids within the main roof; these are insulated with glass fibre material.
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Surveyor 2 Surveyor 1
Location of roosting bats 21 May 2013
Video 1
Location of roosting bats 30 April 2012
Fig. 2: Rear elevation Fig. 3: Front elevation Fig. 4: South-east elevation Fig. 5: Front entarnce porch
The property is located within the boundary of the Yorkshire Dales National Park at Raines Lane, Grassington, North Yorkshire at NGR: SD 999 638, approximately 0.5km west of the village and close to neighbouring residential properties. The nearest designated nature conservation sites are at Grass Wood (Yorkshire Wildlife Trust) and Lower Grass Wood (Woodland Trust) approximately 1.5km north of the site; both woodlands occupy terraces on Great Scar Limestone and have a diverse flora indicative of ancient woodland. The site is within 150 metres of extensive riparian woodland bordering the River Wharfe. The River Wharfe provides high-value feeding, foraging and commuting habitat for bats; the nearest optimal feeding habitat is likely to be 750m west of the site close to Ghaistrill’s Strid.
C1.7 Field surveys undertaken at the site
(1) Site scoping survey including access to roof voids – 21 May 2013 (20.00 – 21.00)
(i) David Fisher (Earthworks Environmental Design), an experienced ecological consultant with 25 years experience of bat ecology, site surveying and monitoring techniques, impact assessments and mitigation guidance in connection with development and planning issues; a founder member of the East Lancashire Bat Group and is involved in research of underground sites throughout the North of England.
(Natural England licence No: 20122876, Conservation, Science and Education).
(ii) George Fisher - field assistant – trainee surveyor / bat worker
(currently un-licensed)
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C1.7 Survey results
Roost inspection:
No bats or signs of roosting bat activity were found inside the roof voids that were inspected (figs. 6 and 7).
Field survey - evening emergence:
The surveyors were positioned on either side of the building as shown in figure 1 (Plan of Site), providing ‘all-round’ coverage of the property; a video recorder was located at the SE corner of the house.
The survey began 20 minutes before sunset; the weather was cool and dry during the evening (max. temperature 9.5º C / min. temperature 6.5º C; humidity: 30% - 40%, cloud cover: 60% - 90%, wind: persistent light wind from NW) providing satisfactory survey conditions
Only a single bat species was recorded during the survey: ie. common pipistrelle (Pipistrellus pipistrellus) a total of 3 bats emerged from a small air grid (and one bat entered) on the upper wall of the front elevation (as located in figure 10) several commuting bats were recorded flying around the property (figures 8 and 9).
Fig. 8: main commuting route around property. Fig. 9: commuting routes around property
Time of activity
Species:
Notes:
21.26 Pipistrelle sp. Unknown species echo-locating near tress in rear garden
21.30 Common pipistrelle Foraging in rear garden
21.32 Common pipistrelle. Bat approaches from east and enters air grid (figure 10)
21.34 Common pipistrelle. Commuting bat approaches from SE and fly around property
21.43 Common pipistrelle. Bat emerges from air grid.
21.43 Common pipistrelle. Second bat emerges from air grid.
21.43 Common pipistrelle Two bats fly around N end of house from front elevation
21.45 Common pipistrelle. Commuting bat approaches from SE and fly around property
21.49 Common pipistrelle. Commuting bat approaches from SE and fly around property
2.51 Common pipistrelle. Commuting bat approaches from SE and fly around property
21.55 Common pipistrelle. Third bat emerges from air grid.
Table 1: showing recorded bat activity during evening emergence survey:
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Fig. 10: roost entry and emergence flight.
C1.8 Interpretation / evaluation of survey results
A small number of common pipistrelle bats are roosting behind a small iron air grid (as shown in fig. 10); one bat entered the roost at dusk and 3 bats emerged. No other emergence activity was recorded; no bats were recorded emerging from any of the roosts that were located by a previous surveyor (30 April 2012).
There is no evidence of a significant day / night roost at this property. There are no signs of any maternity roost; it is very unlikely the site has ever been used as a nursery site. The building is likely to be used by low numbers of common pipistrelles, probably solitary males (or non-breeding adults and juveniles) throughout the year; most bats are likely to be present from April until September.
This is a minor roost site; numbers are unlikely to exceed 5 individuals (size class 1 to 5 bats).
Previous records indicate the presence of common pipistrelle maternity roosts in the locality within 200 meters of the property. Although the actual location of the house is sub-optimal in terms of feeding and foraging habitat, there is high-value riparian habitat along River Wharfe.
Solitary bats or low numbers of bats are likely to roost for short periods wherever suitable crevices exist, specifically under raised roof slates and any suitable features around the roof. Common pipistrelles are highly mobile and frequently change roosts, making it extremely difficult to locate where individuals are likely to be at any one time.
Conclusion:
The surveys have shown that solitary bats are using a number of roosting locations at the southern-most end of the house. A small number of common pipistrelle bats (mostly adult males) are likely to occupy crevices beneath raised stone slates and other suitable features during the summer months..
There is no evidence of a nursery roost, significant day roost or place of hibernation.
With specific reference to the BMG (Guidelines for Proportionate Mitigation - page 39) the presence of small numbers of a common species requires ‘provision of new roost facilities where possible; these need not be exactly like-for-like but should be suitable, based on the species’ requirement’. Additionally, ‘minimal timing constraints or monitoring is required’.
D Impact assessment
D1.1 Short-term impacts: disturbance
Potential disturbance / exposure of solitary common pipistrelles.
As a general guide, the period of least risk of disturbing roosting bats is likely to be 1 September to 31 March; the period highest risk of disturbance to bats is likely to be between 1 April and 31 August.
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D1.2 Long-term impacts:
Roost loss:
The impact of the proposed works on a local bat population is likely to be relatively low (BMG page 39).
D1.3 Long-term impacts:
Fragmentation and isolation: The current conservation significance of the building is relatively low.
The impact of the proposed development on local bat populations is likely to be low.
D1.3 Predicted scale of impact
Temporary disturbance to a minor bat roost; compensation / enhancement measures should include timing constraints (summer months only) and provision of access slates and ridge tiles on the new extensions.
E Land ownership
N/A
F References:
Altringham, JD., (2011) Bats, From Evolution to Conservation. OUP.
Dietz, C., Helversen, O., Nill, D.,(2009) Bats of Britain, Europe and Northwest Africa. A&C Black.
Hundt, L., (2012) BCT Bat Surveys, Good Practice Guidelines – 2nd Edition.
JNCC, (2010), Handbook for Phase 1 Habitat Survey – a Technique for Environmental Survey.
JNCC / BCT., The State of the UK’s bats. NBMP Population Trends 2012.
(1) Provision of bat access slates on extension roof pitches (Natural England – Cumbria team design)
(2) Provision of bat access ridge tiles - (Natural England – Cumbria team design)
(3) Alternative roost slates (Morris batslate)
As appended.
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DOCUMENT 2:
DELIVERY INFORMATION
A Mitigation and Compensation
The overall purpose of the Method Statement is to ensure that bats and their roosts are fully protected to ensure the ‘favourable conservation status of the species’. The Method statement is designed to minimise or remove any potential disturbance to roosting bats; this is most easily achieved through appropriate timing of the works. Works carried out after 1 September and before 31 March, will ensure that any risk to pregnant females or young bats is significantly reduced. The Bat Mitigation Guidelines (BMG) specify that sites with bat roosts with small numbers of common species require ‘provision of new roost facilities where possible. ..and minimal timing constraints’.* *(reference: BMG, Figure 4, page 39 – Guidelines for proportionate mitigation). A Timing constraints
(1) Avoid removal or roof materials during the critical months May, June, July and August when nursery colonies in the area are likely to be active; this is the period when young bats and pregnant females are most vulnerable to disturbance.
(2) The optimum times for re-roofing works (Natural England advice) are considered to be during the spring and autumn periods when bats are least vulnerable to roost disturbance. (Bat Mitigation Guidelines, pp.42 / 43).
Roof works should not begin before 1 September and must be completed by 31 March of the following year after the works have started.
B Works to be undertaken by the ecologist or suitably experienced person
B.1 Capture and exclusion
Capture and exclusion are unlikely to be required.
Roof removal should be supervised by a qualified / experienced ecologist / bat worker in case any roosting bats are disturbed or exposed during the lifting of roof slates and roofing felts. The ecologist must provide a ‘holding box’ in which any captured bats are kept prior to safe release at night.
The ecologist must be on site when the work is ready to commence; the ecologist’s role is to advise site contractors on the safest methods of lifting and removing the slates and other roof materials to avoid causing injury or death of a protected species. The ecologist should be on site throughout the roof removal.
Experience has shown that carefully supervised works are generally very effective.
C Works to be undertaken by the Developer/Landowner
Careful co-ordination is essential to ensure the ecologist is on hand during the actual roof removal;
Complying with mitigation and implementing any compensatory works is the responsibility of the developer.
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C.1 Bat roosts
C1.1 In-situ retention of roost(s)
N/A
C1.2 Modification of existing roosts(s)
N/A
The new extensions must include design adaptations to provide access for bats
(Refer to: Method Statement summary).
C1.3 New roost creation
New roosting opportunities should be incorporated into the design of the new building.
The following recommendations are based on the guidelines for proportionate mitigation (BMG, page 39):
Provision of ridge tiles and access slates within new roof areas.
2 No. ridge tiles (Natural England ridge tile design 4A) should be installed on each new roof section (north and south elevations) enabling cavity-roosting bats to roost beneath roofing materials (ie. under the ridge tiles and between slates and sarking / roofing membranes.
4 No. access slates (Natural England ‘slate’ design detail 1A) to be installed on lower pitches on each new hipped roof; the slates should be placed just above the verges to replicate existing roost opportunities.
Details of both roof access designs are appended.
D Post-development monitoring
Post development inspection is recommended to ensure that access slates are correctly installed.
It is recommended that the contractor liaises with the ecologist during the building operations to ensure the adaptations are appropriate.
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E Flow-chart of mitigation procedures and timing of works
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(2) OBSERVE TIMING CONSTRAINTS
OPTIMAL TIME FOR REMOVAL OF ROOFS is between 1 September and 31 March inclusive.
AVOID the critical months of MAY to AUGUST.
(4) If bats are absent continue with the proposed roofing works.
(5) If any bats are present / or in danger of being disturbed / exposed, they should be safely removed from the site by the ecologist and placed in a secure holding box.
A holding box must be provided on‐site throughout the period of building alterations.
(1) IMMEDIATE CONSIDERATIONS:
Designs must include bat‐friendly adaptations. Consult ecologist if further advice is required.
(3) SUPERVISION OF ROOF SLATE REMOVAL:
Supervision is required during removal of roof slates and felts at the southern‐most end of the house; the supervision should be carried out by a licensed ecologist and should include a ‘toolbox’ talk on‐site to the roofing contractors before any work begins.
ROOFING WORKS: should avoid the critical months: May, June, July and August. Optimal period 1 September to 31 March of the following year. OTHER WORKS: no timing constraints
BMG Table 6.1 Page 37
2. Design adaptations
Purpose-built ridge and slate access slates should be included into the designs at the earliest opportunity. Recommended design specifications are described in COMPENSATORY WORKS – Natural England drawings 1A and 4A - APPENDED.
3.Supervision of demolition
An ecologist / bat worker should be on site at the start of roofing works to provide guidance to contractors and to be available if any bats are disturbed or exposed. Any bats should be safely removed from the site and placed in a holding box.
4. EMERGENCY ADVICE
Call David Fisher (EED) on 01200 446859 (office) or 07709 225783 (mobile); a site visit will be arranged to assess the situation and recover any bats / safely remove them from site.
5. Legal responsibilities
All contractors and project managers should be made aware of the legal protection afforded all species of bat in the UK and procedures should be in place to mitigate for the potential impact on bats before any building or demolition work is undertaken. The onus lies with the applicant to satisfy himself / herself that no offence will be committed if the development goes ahead, regardless of whether planning permission has been granted.
6. Site Contractors.
A copy of this Method Statement must be available to all site / project managers before roofing works are carried out. All site contractors must be aware that bats have been present at this site and a copy of the Method statement should be made available to them.
7. Compliance
The existence of a Method Statement helps to establish a defence against prosecution for intentional (WCA), deliberate (Habitat Regulations.) or reckless (WCA) disturbance of bats or damage to roosts. A Method Statements is normally required by the local planning authority to ensure that procedures are in place before the development works are carried out. It is the responsibility of the LPA to ensure that the proposed works would not result in breaches of the Habitat Regulations. Post-development monitoring is not essential, although the local planning authority may require further inspection of the site to ensure that the mitigation and enhancement works have been carried out appropriately.
An EPS development licence is not required where it can be clearly demonstrated that satisfactory mitigation and enhancement works have been considered and implemented thus avoiding offences being committed under the Habitat Regulations.
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ENHANCEMENT / COMPENSATORY WORKS
ACTION
METHOD:
1.
Ridge access tiles
2.
Access slates
PROVIDE:
2 No. ridge tiles (Natural England ridge tile design 4A) should be installed on each new roof section (extensions to north and south elevations) enabling common pipistrelle bats to roost beneath roofing materials (ie. under the ridge tiles and between slates and sarking / roofing membranes.
PROVIDE:
4 No. access slates (Natural England ‘slate’ design detail 1A) to be installed on lower pitches on each new hipped roof; the slates should be placed just above the verges to replicate existing roost opportunities.
Or alternatively:
The Morris Bat Slate is a similar design to the bat access slate 1A above; full details are attached.
A4 versions of these designs are shown in Appendix A.
These modifications are relatively easy to install and / or modify. To be fully effective, the specifications should be discussed with an ecological consultant to ensure correct installation.
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APPENDIX A
Ridge access tile:
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APPENDIX B
Bat access slate:
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APPENDIX C
Morris bat access slate (an alternative method)
This fully illustrated PDF document is available online
