Case Study: Dredging the entrance to the Lower

Myall River and impacts on migratory shorebirds.Myall River and impacts on migratory shorebirds.

Stephen AmbroseAmbrose Ecological Services Pty Ltd

Separating Science from Politics:

How do we separate ecological impact assessment fromoutside pressures and influences?

Walking the Political Tightrope:

What if our ecological conclusions of significance arequestioned by the client?

Case Study: Dredging the entrance to the Lower MyallRiver and impacts on migratory shorebirds.

1. Perceived deterioration in water quality (water clarity &reduced salinity) in Lower Myall River.

2. Episodic occurrences of diseased fish and a decline in oysterfarming in Lower Myall River.

3. Sand erosion of Jimmys Beach (following nourishment).

4. Connection of Corrie Island to the Winda Woppa Spit andassociated impacts of feral animals on the Ramsar wetlandand migratory bird species.

5. Erosion of Corrie Island.

6. Restricted boating access to the Myall River.

Myall River Inter-agency Task Group

An initiative of Katrina Hodgkinson, NSW Minister for PrimaryIndustries & convened in March 2012.

Representation on Committee:

NSW Department of Primary Services (DPI) – Regional Services. NSW Department of Primary Services (DPI) – Regional Services.

DPI – Fisheries.

Office of Environment & Heritage (OEH).

Port Stephens – Great Lakes Marine Park Authority.

NSW Department of Trade & Investment (DTI) – Crown Lands.

Port Stephens Council.

Great Lakes Council.

1. Highly coloured waters in Lower Myall River is a naturalphenomenon (mainly tannins) and has been persistent inrecent times due to rainfall.

2. Dredging the eastern channel would not improve water clarityor low salinity during periods of freshwater outflows from Myallor low salinity during periods of freshwater outflows from MyallLakes, but would be beneficial during lower than average rainfallperiods.

3. Diseased fish is a winter phenomenon (prolonged coldtemperatures, low salinity) and not related to sand shoaling.

4. Decline in oyster industry due to natural processes (e.g.freshwater events, siltation from flooding, river bed & bankscouring, mangrove establishment).

5. Movement of sand from Jimmys Beach not a significantcontributor to sand shoaling of the eastern channel.

6. Shoreline recession of Corrie Island has slowed due to exposureof coffee rock (cemented sands). A dredged channel would notof coffee rock (cemented sands). A dredged channel would notimpact on this erosion.

7. Limited access to Corrie Island by large predators is withinnatural limits & does not compromise its value as a shorebirdroosting and feeding area.

8. The northern channel (stable) already provides recreationalboating access to Myall River. Creation & maintenance ofeastern channel too expensive & difficult to create & maintain.

32 migratory shorebird spp. & 10 Australian resident shorebirdsrecorded since 1970 (Stuart 2004).

22 migratory shorebird spp. recorded in HBOC surveys since 2004= 25% of all shorebird bird species that occur in Australia (Stuart= 25% of all shorebird bird species that occur in Australia (Stuart2011).

> 1% of the Eastern Curlew and Whimbrel populations that use theEast Asia-Australasia Flyway (Smith 1991).= globally significant wetland (Watkins 1993).

Significant wetland for at least 3 decades for the Eastern Curlewpopulation that over-winters in NSW (Stuart 2011).

Eastern Curlew Whimbrel

Australian Pied Oystercatchers (APOs)

Up to 1.4% of the global population of Australian Pied Oystercatchers(APOs) at Port Stephens throughout the year (summer max = 192,(APOs) at Port Stephens throughout the year (summer max = 192,winter max = 154).

In 2008-09 HBOC recorded over 200 APOs in the Hunter region= slightly lower than previous population estimates for the entireAustralian coastline (232-250 individuals) (Stuart 2010).

Therefore, Port Stephens is a globally, nationally & regionally-significant wetland for APOs throughout the year.

Bar-tailed Godwits

> 500 individuals in summer = 0.5% population that visits Australia(Stuart 2011).

122 – 424 individuals in winter. Most important wetland for Bar-tailedGodwits over-wintering in NSW (Stuart 2011).Godwits over-wintering in NSW (Stuart 2011).

Threatened shorebird species recorded on Winda Woppa Sand Shoal

Beach Stone-curlew * Sooty Oystercatcher * Australian Pied Oystercatcher * Lesser Sand-plover Black-tailed Godwit Terek Sandpiper Little Tern

Potential Impacts of Proposal

Benefit

Reduced accessibility to important shorebird foraging and roostingareas by feral animals, pet dogs etc.

Detrimental ImpactsDetrimental Impacts

Loss of foraging and roosting habitat (minimal).

Increased disturbances to roosting & foraging shorebirds fromrecreational boating (incl. jet skis) , dredging activities & fish baitcollectors (likely to be significant).

Recommendations

Referral to Commonwealth Govt under the EPBC Act.

Potential significant impacts on:

Myall Lakes Ramsar site.

Lifecycles of globally significant populations of several migratoryshorebirds (Eastern Curlew* & Bar-tailed Godwit*).

* Display high site-fidelity. Disturbances & habitat loss may causethem to abandon preferred foraging & roosting habitat. Slowerbuild-up of body fat = delayed or abandonment of departure tobreeding grounds in northern hemisphere.

Species Impact Statement

Beach Stone-curlew Sooty Oystercatcher Australian Pied Oystercatcher Australian Pied Oystercatcher

Potential for significant impacts on the status of local and state-widepopulations of each species from habitat loss and disturbances.

“Green Tape”

Likely Perception of Local Community:Unnecessary commitment of additional time and financial resourcesto investigate potential environmental impacts that are not likely tobe significant.

Subsequent Considered EcologicalResponse by GLC

Shorebird Impact Assessment Report needs to:

1. Consider previous history of disturbance/non-disturbance to shorebirdswhen eastern channel existed.

Consultant Response: Past presence of birds does not necessarily mean noimpact. Over-wintering birds may be individuals impacted by disturbances andimpact. Over-wintering birds may be individuals impacted by disturbances andunable to migrate to breeding grounds. Need for further investigation.

2. Consider that no dredging = increased risk of disturbance (humans, feralanimals) and weed invasion from Winda Woppa Spit.

Consultant Response: These risks already present, unlikely to change overtime; need to be policed more efficiently. Likely to be increased disturbancesas a result of dredging, increase and nature of boat traffic, increased fish bait

collection.

3. Support the claim that dredging would result in increased watercraftactivity close to significant bird habitat.

Consultant Response: No current or past data, or predictive modelling, oftype, abundance of watercraft activity or boating routes. Such modellingtype, abundance of watercraft activity or boating routes. Such modellingneeds to be done as part of SIS. Eastern channel closer to significant birdhabitat, so likely to be greater watercraft activity impacts.

4. Identify full range of impact avoidance, amelioration and offsettingimpacts.

Consultant Response: Impossible to recommend effective strategies underexisting proposal and absence of additional data that could be collectedduring SIS.

Mr Alan Stuart (Hunter Bird Observers Club)

Dr Clive Minton (Australia’s foremost wader expert)

Mr Phil Straw (Vice-Chair, Australasian Wader Studies Group)Mr Phil Straw (Vice-Chair, Australasian Wader Studies Group)

Dr Peter Scanes (Head, Waters & Coastal Science, OEH)

Dr Gillian Dunkerley (ornithologist & ecologist, OEH)

Role of Ecological Consultant in Ensuring ESD

Need to understand and appreciate: client’s needs opinions of the broader community political , economic & social context of proposal.

BUT:

At the end of the day our obligation is to provide sound, expertecological advice that is not prejudiced by client or communityopinion (impartiality).

If advice not accepted, even after consultation with all parties, do youbecome an advocate for a specific ecological outcome?

Answer: Business and ethical decision that will vary with eachsituation and consultant.