Population Declines of King and Common Eiders of the Beaufort Sea

Abstract

King (Somateria spectabilis) and Common Eiders (S. mollissima v-nigra) wintering off western North America migrate past Point Barrow, Alaska and across the Beaufort Sea to nest in northern Alaska and northwestern Canada. Migration counts were conducted by various researchers at Point Barrow during 1953, 1970, 1976, 1987, 1994, and 1996. We examined population trends by standardizing the analysis of the migration counts in all years. Based on this standardized procedure, the King Eider population appeared to remain stable between 1953 and 1976 but declined by 56% (or 3.9% year−1) from approximately 802,556 birds in 1976 to about 350,835 in 1996. The Common Eider population declined by 53% (or 3.6% year−1) from approximately 156,081 birds in 1976 to about 72,606 in 1996. Reasons for the declines are unknown.

A natural antipredation experiment: predator control and reduced sea ice increases colony size in a long‐lived duck

“…However, many natural eider populations seem to be showing a showing a negative trend in density or number, despite the fact that the climate is getting warmer (e.g., Gilchrist and Robertson ; Suydam et al. ; Hario and Selin ; Merkel ; Hario and Rintala ; but see D'Alba et al. ; Merkel ).…”

“…However, many natural eider populations seem to be showing a showing a negative trend in density or number, despite the fact that the climate is getting warmer (e.g., Gilchrist and Robertson 1998;Suydam et al 2000;Hario and Selin 2002;Merkel 2004;Hario and Rintala 2006;but see D'Alba et al 2010;Merkel 2010). This eider-climatechange paradox must mean that there are other factors limiting the positive effect of climate on reproduction.…”

The Pacific Arctic Region

“…Endangered Species Act, king eiders ( S. spectabilis ) and common eiders ( S. mollissima ) declined by over 50 % from 1976 to 1996, and long-tailed ducks ( Clangula hyemalis ) decreased by 75 % from 1977 to 1994 (Hodges et al 1996 ;Suydam et al 2000 ). Of these, spectacled eiders ( Somateria fi scheri ) and steller's eiders ( Polysticta stelleri ) are listed as threatened under the U.S.…”

Predators, alternative prey and climate influence annual breeding success of a long‐lived sea duck

“…The common eider (Somateria mollissima) is a colonial nesting sea duck, and has experienced long-term declines across much of its (sub-)Arctic breeding range (Robertson & Gilchrist 1998;Suydam et al 2000;Merkel 2004). In addition to its role in coastal and marine ecosystems, the common eider is important both economically and for subsistence harvest in northern communities.…”