1. Case Study: Dredging the entrance to the Lower
Myall River and impacts on migratory shorebirds.Myall River and impacts on migratory shorebirds.
Stephen Ambrose
Ambrose Ecological Services Pty Ltd

2. Separating Science from Politics:
How do we separate ecological impact assessment from
outside pressures and influences?
Walking the Political Tightrope:
What if our ecological conclusions of significance are
questioned by the client?
Case Study: Dredging the entrance to the Lower Myall
River and impacts on migratory shorebirds.

6. 1. Perceived deterioration in water quality (water clarity &
reduced salinity) in Lower Myall River.
2. Episodic occurrences of diseased fish and a decline in oyster
farming in Lower Myall River.
3. Sand erosion of Jimmys Beach (following nourishment).
4. Connection of Corrie Island to the Winda Woppa Spit and
associated impacts of feral animals on the Ramsar wetland
and migratory bird species.
5. Erosion of Corrie Island.
6. Restricted boating access to the Myall River.

7. Myall River Inter-agency Task Group
An initiative of Katrina Hodgkinson, NSW Minister for Primary
Industries & 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.

8. 1. Highly coloured waters in Lower Myall River is a natural
phenomenon (mainly tannins) and has been persistent in
recent times due to rainfall.
2. Dredging the eastern channel would not improve water clarity
or low salinity during periods of freshwater outflows from Myallor low salinity during periods of freshwater outflows from Myall
Lakes, but would be beneficial during lower than average rainfall
periods.
3. Diseased fish is a winter phenomenon (prolonged cold
temperatures, 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 & bank
scouring, mangrove establishment).

9. 5. Movement of sand from Jimmys Beach not a significant
contributor to sand shoaling of the eastern channel.
6. Shoreline recession of Corrie Island has slowed due to exposure
of coffee rock (cemented sands). A dredged channel would notof coffee rock (cemented sands). A dredged channel would not
impact on this erosion.
7. Limited access to Corrie Island by large predators is within
natural limits & does not compromise its value as a shorebird
roosting and feeding area.
8. The northern channel (stable) already provides recreational
boating access to Myall River. Creation & maintenance of
eastern channel too expensive & difficult to create & maintain.

13.  32 migratory shorebird spp. & 10 Australian resident shorebirds
recorded 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 (Stuart
2011).
 > 1% of the Eastern Curlew and Whimbrel populations that use the
East Asia-Australasia Flyway (Smith 1991).
= globally significant wetland (Watkins 1993).
 Significant wetland for at least 3 decades for the Eastern Curlew
population that over-winters in NSW (Stuart 2011).

14. Eastern Curlew Whimbrel

15. 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 entire
Australian coastline (232-250 individuals) (Stuart 2010).
 Therefore, Port Stephens is a globally, nationally & regionally-
significant wetland for APOs throughout the year.

16. 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-tailed
Godwits 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

17. Potential Impacts of Proposal
Benefit
Reduced accessibility to important shorebird foraging and roosting
areas by feral animals, pet dogs etc.
Detrimental ImpactsDetrimental Impacts
 Loss of foraging and roosting habitat (minimal).
 Increased disturbances to roosting & foraging shorebirds from
recreational boating (incl. jet skis) , dredging activities & fish bait
collectors (likely to be significant).

18. Recommendations
Referral to Commonwealth Govt under the EPBC Act.
Potential significant impacts on:
 Myall Lakes Ramsar site.
 Lifecycles of globally significant populations of several migratory
shorebirds (Eastern Curlew* & Bar-tailed Godwit*).
* Display high site-fidelity. Disturbances & habitat loss may cause
them to abandon preferred foraging & roosting habitat. Slower
build-up of body fat = delayed or abandonment of departure to
breeding grounds in northern hemisphere.

19. 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-wide
populations of each species from habitat loss and disturbances.

20. “Green Tape”
Likely Perception of Local Community:
Unnecessary commitment of additional time and financial resources
to investigate potential environmental impacts that are not likely to
be significant.

21. Subsequent Considered Ecological
Response by GLC
Shorebird Impact Assessment Report needs to:
1. Consider previous history of disturbance/non-disturbance to shorebirds
when eastern channel existed.
Consultant Response: Past presence of birds does not necessarily mean no
impact. Over-wintering birds may be individuals impacted by disturbances andimpact. Over-wintering birds may be individuals impacted by disturbances and
unable to migrate to breeding grounds. Need for further investigation.
2. Consider that no dredging = increased risk of disturbance (humans, feral
animals) and weed invasion from Winda Woppa Spit.
Consultant Response: These risks already present, unlikely to change over
time; need to be policed more efficiently. Likely to be increased disturbances
as a result of dredging, increase and nature of boat traffic, increased fish bait
collection.

22. 3. Support the claim that dredging would result in increased watercraft
activity close to significant bird habitat.
Consultant Response: No current or past data, or predictive modelling, of
type, abundance of watercraft activity or boating routes. Such modellingtype, abundance of watercraft activity or boating routes. Such modelling
needs to be done as part of SIS. Eastern channel closer to significant bird
habitat, so likely to be greater watercraft activity impacts.
4. Identify full range of impact avoidance, amelioration and offsetting
impacts.
Consultant Response: Impossible to recommend effective strategies under
existing proposal and absence of additional data that could be collected
during SIS.

23. 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)

25. 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, expert
ecological advice that is not prejudiced by client or community
opinion (impartiality).
If advice not accepted, even after consultation with all parties, do you
become an advocate for a specific ecological outcome?
Answer: Business and ethical decision that will vary with each
situation and consultant.