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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

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Table 1-2. Results <strong>of</strong> simulation which assumes mean r = 0,5 = 0.21 for population sizes corresponding to<br />

classification criteria ix this plan. The last columnis given for comparison so that managers can easily see <strong>the</strong><br />

amount <strong>of</strong> time for research <strong>and</strong> management actions from <strong>the</strong> abundance threshold levels if a population was to start<br />

declining at a rate that would warrant endangered status (i.e.. r ~ -0.05).<br />

POPULATION SIZE<br />

(PAIRS)<br />

PROBABILITY OF<br />

EXTINCTION IN 500<br />

YEARS<br />

YEARS TO REACH<br />

CRITICAL WITH<br />

r = -0.051<br />

2,000 0.102 36<br />

3,000 0.081 45<br />

5,000 0.063 57<br />

6,000 0.056 58<br />

8,500 0.050 65<br />

10,000 0.048 65<br />

25,000 0.025 106<br />

Appendix I - Page 16

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