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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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B2. 1.1. Implement YKD satellite transmitter prolect. Transmitter implants into<br />

birds at Hock Slough, YKD, was initiated in 1993 <strong>and</strong> should continue until sample<br />

size requirements are met. Preferably, <strong>the</strong> YKD telemetry work should be exp<strong>and</strong>ed to<br />

include an additional study site to test whe<strong>the</strong>r YKD breeders use common postbreeding<br />

habitats. (Completed in 1995.)<br />

B2. 1.2. Implement NS satellite transmitter proiect. This project would follow <strong>the</strong><br />

YKD project. (Initiated in 1995.)<br />

B2. 1.3. implement AR satellite transmitter proiect. - This project.would follow <strong>the</strong><br />

NS project. (Initiated in 1995.)<br />

B2.2. Identify, describe <strong>and</strong> monitor use <strong>of</strong> at-sea habitats. Initial survey efforts should<br />

be based on: (1) locations derived from satellite telemetry studies, (2) o<strong>the</strong>r direct<br />

observations, <strong>and</strong> (3) an assessment <strong>of</strong> probable habitats such as polynyas. Surveys may be<br />

aerial or ship-board, depending on location <strong>and</strong> logistical constraints. O<strong>the</strong>r opportunities<br />

to obtain at-sea distribution <strong>and</strong> habitat data opportunistically, such as marine mammal<br />

surveys, should also be pursued. These surveys will confirm <strong>and</strong> describe <strong>the</strong> extent to<br />

which <strong>Spectacled</strong> <strong>Eider</strong>s use <strong>the</strong> areas where transmittered birds are recorded or nontransmittered<br />

birds are observed, preferably in <strong>the</strong> year when satellite or observation data<br />

are obtained. Initial efforts should also be used to assess <strong>the</strong> feasibility <strong>of</strong> a geographically<br />

extensive, multi-year effort designed to identify <strong>the</strong> major at-sea areas <strong>and</strong> provide data on<br />

distribution, numbers, sex <strong>and</strong> age ratios, <strong>and</strong> annual geographical variability <strong>of</strong> use.<br />

If feasible, identifying summering sites for non-breeding birds would be valuable to<br />

determine <strong>the</strong> magnitude <strong>and</strong> sex <strong>and</strong> age composition <strong>of</strong> <strong>the</strong> non-breeding components <strong>of</strong><br />

each population. If <strong>the</strong> number <strong>of</strong> non-breeding birds could be determined annually by<br />

population, <strong>the</strong>n population trends on <strong>the</strong> breeding grounds could be interpreted more<br />

accurately.<br />

The geographic range <strong>of</strong>juveniles away from <strong>the</strong> breeding grounds should also be<br />

determined, especially by tracking transmittered females after breeding (assuming juveniles<br />

stay with females) orjuveniles after fledging (see tasks C2. 1 <strong>and</strong> C2.2). In particular, it is<br />

important to determine locations where juveniles congregate after fledging <strong>and</strong> during <strong>the</strong><br />

pre-breeding years. Sincejuvenile mortality is thought to be substantial immediately after<br />

<strong>the</strong>y move from nesting grounds to salt water, valuable demographic data might be<br />

obtained if fall staging areas were identified <strong>and</strong> surveyed. Information on reproductive<br />

success <strong>of</strong> <strong>the</strong> YKD population could be obtained by conductin~ 2 photo flights <strong>of</strong>Norton<br />

Sound in early August <strong>and</strong> late September to determine changes in sex <strong>and</strong> age ratios. In<br />

addition, surveys <strong>of</strong> eiders using Kuskokwim shoals (<strong>and</strong> areas south) during August<br />

should be conducted.<br />

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