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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C2. 1.1.1. Conduct adult female <strong>and</strong> brood survivorship studies at Hock Slough <strong>and</strong><br />
Kigigak Isl<strong>and</strong> on <strong>the</strong> YKD. A color marking project was initiated in<br />
1993 at two study sites <strong>and</strong> is on-going. This study should be exp<strong>and</strong>ed<br />
to monitor survival <strong>of</strong> broods <strong>and</strong> hens after hatch <strong>and</strong> examine<br />
differences in survival <strong>of</strong> hens exposed <strong>and</strong> not exposed to lead.<br />
C2. 1.1.2. Tdentify a study site on <strong>the</strong> YKD free <strong>of</strong> accumulated lead shot for a<br />
study <strong>of</strong> adult female <strong>and</strong> brood survivorship<br />
C2. 1.1.3. Conduct adult female <strong>and</strong> brood survivorship study at lead free study site<br />
Qfl±~YKD 4<br />
C2. 1.2. Implement adult female <strong>and</strong> brood survivorship study on <strong>the</strong> NS<br />
C2.i.3. Implement adult female <strong>and</strong> brood survivorship study in AR<br />
C2.2. Quantify juvenile survival from fledging to recruitment, <strong>and</strong> determine age at first<br />
breeding <strong>and</strong> natal philopatry. If recruiting birds return to <strong>the</strong>ir natal area or o<strong>the</strong>r<br />
breeding areas that are being intensively studied, attaching color markings to juvenilesjust<br />
before fledging may provide important data on recruitment rates, age <strong>of</strong> first breeding <strong>and</strong><br />
natal phiopatry. Success will depend in part on attaining sufficient sample sizes to<br />
overcome presumed high mortality rates between fledging <strong>and</strong> recruitment. A<br />
supplemental or alternate approach to estimate juvenile survival with telemetry is included<br />
in task C2.3. <strong>and</strong> a potential alternative for determining population age structure estimates<br />
is included in task Cl.<br />
Preliminary marking is ongoing <strong>and</strong> should provide data for determining sample sizes<br />
necessary to estimate survival with power = 0.8. If <strong>the</strong> project is feasible <strong>and</strong> sample<br />
sizes can be obtained, color marking should be implemented on a wider scale. In cases<br />
where funds are not available to complete b<strong>and</strong>ing projects for both adult females <strong>and</strong><br />
juveniles, <strong>the</strong> adult birds should receive priority.<br />
C2.2. 1. Implement juvenile survivorship study on <strong>the</strong> YKD<br />
C2.2.2. Implement iuvenile survivorship study on <strong>the</strong> NS<br />
C2.2.3. Implement juvenile survivorship study in AR<br />
C2.3. Determine location <strong>and</strong> timing <strong>of</strong>juvenile mortality from fledging to one year<br />
Survivorship data obtained through leg color-b<strong>and</strong>ing or o<strong>the</strong>r methods (task C2.2) may be<br />
inadequate because <strong>of</strong>low return rates due ei<strong>the</strong>r to high mortality or emigration. Data on<br />
post-fledging <strong>and</strong> first winter mortality might be attainable by attaching satellite or<br />
conventional transmitters to juveniles <strong>and</strong> tracking <strong>the</strong>m. Radio transmitters would be<br />
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