A. Status of the Spectacled Eider - U.S. Fish and Wildlife Service
A. Status of the Spectacled Eider - U.S. Fish and Wildlife Service
A. Status of the Spectacled Eider - U.S. Fish and Wildlife Service
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contaminants within <strong>Spectacled</strong> <strong>Eider</strong> marine <strong>and</strong> breeding ranges needs to be compiled <strong>and</strong><br />
evaluated to identify which contaminants may be adversely affecting <strong>Spectacled</strong> <strong>Eider</strong><br />
populations (see task Dl). The summary should: (1) deseribe contaminant concentrations<br />
recorded in eiders, o<strong>the</strong>r marine birds <strong>and</strong> marine mammals; (2) interpret inter-population<br />
variability in contaminant levels; <strong>and</strong> (3) compare contaminant levels to concentrations<br />
found in o<strong>the</strong>r species <strong>and</strong> to levels known to cause physiological or behavioral effects in<br />
waterfowl <strong>and</strong> marine birds (toxic <strong>and</strong> chronic effects) (initiated 1994).<br />
CS.2. Prepare summary report about competition for food <strong>and</strong> loss <strong>of</strong> food supplies due to<br />
benthic disturbance. The potential relationships between competition <strong>and</strong> <strong>the</strong> observed<br />
historical declines <strong>and</strong> recovery should be evaluated <strong>and</strong> summarized in a report.<br />
Population trends, long-term distribution, <strong>and</strong> food habits <strong>of</strong> potential competitors<br />
including o<strong>the</strong>r marine birds, walrus, <strong>and</strong> Gray Whales should be examined <strong>and</strong> compared<br />
with <strong>the</strong>se traits for <strong>Spectacled</strong> <strong>Eider</strong>s (see task El). The spatial <strong>and</strong> temporal overlap <strong>of</strong><br />
<strong>Spectacled</strong> <strong>Eider</strong>s with potential competitors should be compiled in a GIS data base. All<br />
available data on benthic fauna for at-sea <strong>Spectacled</strong> <strong>Eider</strong> habitat should be compiled. In<br />
addition to direct competition, food supplies may be inadequate due to benthic damage<br />
caused by Gray Whales displacing benthic substrates while <strong>the</strong>y feed. Thus indirect<br />
competition through benthic disturbance should be included as part <strong>of</strong> this hypo<strong>the</strong>sis<br />
testing. The levels <strong>of</strong> resource use overlap, niche breadths, competitor abundance, <strong>and</strong><br />
benthic disturbance should be evaluated (this task may overlap with tasks CS.5 <strong>and</strong> C5.9).<br />
CS.3. Prepare summary report about harvest. The potential relationships between harvest<br />
<strong>and</strong> <strong>the</strong> observed historical declines <strong>and</strong> recovery should be evaluated <strong>and</strong> summarized in a<br />
report. Historical subsistence harvest survey data, where available, <strong>and</strong> anecdotal data<br />
should be collected <strong>and</strong> examined for comparatibility <strong>and</strong> potentially for use in examining<br />
historical changes in magnitude <strong>and</strong> distribution <strong>of</strong> harvest. Historical sport harvest data<br />
should be derived from ADF&G <strong>and</strong> <strong>Service</strong> harvest surveys <strong>and</strong> anecdotal data. Factors<br />
that may have contributed to historical changes in <strong>the</strong> subsistence <strong>and</strong> sport harvests should<br />
be identified.<br />
C5.4. Prepare summary report about predation. The potential relationships between<br />
predation on eggs, ducklings, <strong>and</strong> adults <strong>and</strong> <strong>the</strong> observed historical declines <strong>and</strong> recOveryshould<br />
be evaluated <strong>and</strong> summarized. The evaluation should consider: (1) gull population<br />
trends, <strong>and</strong> foraging behavior <strong>and</strong> diets (task G3); (2) correlations between gull <strong>and</strong> eider<br />
densities <strong>and</strong> changes in those densities on <strong>the</strong> YKD; (3) changes in fox populations on<br />
both <strong>the</strong> YKD <strong>and</strong> <strong>the</strong> NS, <strong>and</strong> effects <strong>of</strong> fox control on waterfowl predation (task Gi);<br />
<strong>and</strong> (4) population-level trends for o<strong>the</strong>r fox <strong>and</strong> gull prey species compared with<br />
<strong>Spectacled</strong> <strong>Eider</strong> population trends.<br />
CS.5. Prepare summary report about Bering Sea <strong>Fish</strong>eries. The potential relationships<br />
between fisheries activities <strong>and</strong> <strong>the</strong> observed historical declines <strong>and</strong> recovery should be<br />
evaluated <strong>and</strong> summarized. Ifpreliminary assessment points to potential interaction<br />
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