Island Habitats for Wading Birds

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1 Island Habitats for Wading Birds A criticallylimiting resource in the predatorrich northeast coastal zone Katharine C. Parsons Manomet Center for Conservation Sciences

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3 Short-distance migrants Most east coast birds winter in US southeast and Caribbean Some northern individuals winter in New England Return to breeding sites in early spring

4 Herons return to nest-sites used successfully in the past

5 Many species are highly colonial

6 Clutch size ranges from 3-5 eggs

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8 Wading birds commute to foraging habitats within 20 km of colony

9 Nestling production reflects wetland quality

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11 Common wading birds in NYH

12 Heron populations grow in NYH Total Nests Year

13 Passage of Clean Water Act reduces raw sewage inputs to harbor

14 Aquatic food chain re-established in inner harbor waterways

15 Inner harbor islands colonized

16 North Brother Is South Brother Is Shooters Is Prall s Is Isle Meadows--1988

17 Partnerships developed to study and conserve herons

18 Mean Egg Production 2Mean Egg Production Mean Egg Production Mean Egg Production

19 Oil spills of 1990 killed wintering birds and degraded tidal wetlands

20 3 Oil Spill Oil Spill Mean Nestling Production Mean Nestling Production Oil Spill Oil Spill Mean Nestling Production Mean Nestling Production

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22 Manomet s regional wading bird research and conservation projects Breeding Foraging Toxicology Management Coalitions

23 Hatching success higher in urban estuaries Hatching Success Hatching Success DEL NYH NAN BOS 60 DEL NYH NAN BOS Hatching Success Hatching Success DEL NYH NAN BOS 60 DEL NYH NAN BOS

24 Fledging success higher in urban estuaries Fledging Success DEL NYH NAN BOS Fledging Success DEL NYH NAN BOS Fledging Success DEL NYH NAN BOS Fledging Success DEL NYH NAN BOS

25 Egg inviability urban estuaries; Egg predation non non-urban estuaries Inviab le 46% Predated 54% In vi abl e 71% Pr ed ated 29% NYH NYH Inviable 35% Inviable 28% Pre dated 65% DEL Predated 72% DEL

26 Starve d 52% Predate d 48% Starved 53% Predated 47% NYH NYH Nestling predation non non-urban estuaries Starved 26% Starved 22% Predated 74% DEL Pre dated 78% DEL

27 Why are predators having such a devastating impact in non-urban heronries? Predator Nests/1000 Heron Nests DEL NYH

28 Manomet s toxicological studies in non-urban estuaries show pesticide exposure in wading birds

29 Wading birds are exposed to new generation (post-ddt) insecticides through skin through diet

30 Pesticides detected in heron diet and on skin Diet dimethoate, parathion, malathion, methamidophos, chlorpyrifos Skin phorate, naled

31 Neurotoxic pesticides deplete key enzymes in exposed birds Mean cholinesterase levels are 10-20% lower in non-urban estuaries than in New York Harbor

32 Low cholinesterase increases vulnerability to predators

33 Predators cause nest-site and colony-site abandonments Number of Nests Stone Harbor New Jersey s largest heronry Number of Nests Pea Patch Island largest heronry on the east coast

34 Colony-site selection since 1970s increases isolation of nesting birds 1970s mainland 53% island 47% mainland 11% 1990s island 89%

35 Wading birds actively colonize urban estuaries mid-1970s to mid-1990s Total Nests New York Harbor 15% increase Year N Breeders Boston Harbor 114% increase

36 Wading birds move to urban estuaries Baltimore Harbor New York Harbor Boston Harbor Island rich Pesticide use minimal

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38 NYH inner harbor wading bird populations have declined since mid-1990s Total Nests

39 Inner harbor islands abandoned; Outer harbor islands colonized Goose Is--stable N. Brother Is decline? Huckleberry Is--decline S. Brother Is--stable x Canarsie Pol--increase x x Hoffman Is--stable

40 Productivity in inner harbor not sustainable SNEG BCNH CAEG Fledglings/nest

41 Low productivity results from industrial contaminants Concentration (ppm) Regional NYH COD BOS DEL NAN PCBs Concentration (pg/g) Coastal NY Newark Bay Outer Harbor E. Long Is dioxins

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43 Total NY/NJ Harbor Estuary populations peaked in mid-1990s N nests

44 Boston Harbor populations decimated N Breeders

45 Coastal wading birds declining regionally N Breeding Birds SNEG BCNH 1970s 1980s 1990s 2000s

46 In non-urban estuaries, wading birds exposed to pesticides Neurotoxins increase vulnerability to predators Non-urban heronries abandoned due to high predation rates Wading birds colonize New York Harbor In NYH and other urban estuaries, wading birds exposed to industrial contaminants Productivity below sustainable level for more than a decade Adults in population not replaced In region, total wading bird populations decline by nearly 40%

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48 Waterbird Conservation BCR 14 PBCR 79 # BCR 30 PBCR 78 Mid-Atlantic/New England/Maritimes Waterbird Conservation Working Group

49 NYH clean-up efforts Toxics Work Group -Contaminants Assessment and Reduction Project Dredged Material Management Integration Work Group Habitats Work Group

50 Protection from pesticides Food Quality Protection Act National Pesticides Coalition Research needs more apparent Wildlife-Human linkages

51 Manomet s continuing commitment Pesticide Best Management Practices Wildlife/Human Health Coalition Waterbird Conservation Toxics monitoring

52 The Science of Saving Nature As one of the nation's oldest independent environmental research organizations, Manomet conducts original research on natural systems and wildlife. We use our science to bring people together and guide them in the development of practical strategies that improve conditions for wildlife, habitats and people.