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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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0<br />

86 87 88 89 90 91 92 93 94 95<br />

Yukon-Kuskokwim Delta Ground Plots<br />

86 87 88 89 90 91 92 93 94 95<br />

Year<br />

Figure 3. Recentpopulationtrends for <strong>Spectacled</strong> <strong>Eider</strong>s on <strong>the</strong> Yukon-Kuskokwim Delta based on intensive aerial<br />

surveys <strong>and</strong> r<strong>and</strong>om ground plot sampling. Since 1988, an intensive aerial survey flown on <strong>the</strong> coastal fringehas<br />

monitored eiderpopulations. The index combined singles or pairs observed for <strong>Spectacled</strong> <strong>and</strong> unidentified ciders<br />

<strong>and</strong>was not con-ected for incomplete visibility; most unidentified eiderswere probably <strong>Spectacled</strong> <strong>Eider</strong>s. The 1986-<br />

1995 estimates for nests were derived by searching r<strong>and</strong>omly located plots in central coast strata <strong>and</strong> exp<strong>and</strong>ing by <strong>the</strong><br />

inverseproportion <strong>of</strong>total aerial observations within <strong>the</strong> sampled area. Expansion in 1986 <strong>and</strong> 1987 was based on<br />

<strong>the</strong> average <strong>of</strong> 1988-1991 aerial observations. (Figure by R. Stehn)<br />

5

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