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USGS · 70022500

Late summer survival of adult female and juvenile spectacled eiders on the Yukon-Kuskokwim Delta, Alaska

Paul L. Flint·J. Barry·J.A. Morse·T.F. Fondell
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Abstract

We used radio-telemetry to examine survival of adult female and juvenile Spectacled Eiders (Somateria fischeri) from 30 days after hatch until departure from the Yukon-Kuskokwim Delta (YKD) during 1997-1999. Juvenile survival was 71.4%; adult female survival was 88.5%. Mink (Mustella vison) were the most common predator identified for both adults and juveniles. Detectable levels of lead were found in bones of 74% of juvenile carcasses recovered and 21% had levels indicative of acute exposure. Average age at departure was 59 ?? 1 days old for juveniles and 56 ?? 1 days after hatch for adults. Most broods (60.5%) departed the YKD synchronously. Overall our data indicate that mortality during the latter half of brood-rearing is higher than previously thought. We conclude that brood rearing is a period of high mortality for brood-rearing females and that lead poisoning is responsible for reductions in juvenile survival to fledging. Received 15 February 2000, accepted 1 April 2000.

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Paul L. Flint, J. Barry, J.A. Morse, T.F. Fondell. 2000. Late summer survival of adult female and juvenile spectacled eiders on the Yukon-Kuskokwim Delta, Alaska. https://pubs.usgs.gov/publication/70022500

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