In the 2012 President's Budget Request, the National Biological Information Infrastructure (NBII) is terminated. As a result, all resources, databases, tools, and applications within this web site will be removed on January 15, 2012. For more information, please refer to the NBII Program Termination page.
[Pacific Common Eider pair - Photo by Jeff Wasley]
The Pacific subspecies of Common Eider
(Somateria mollissima v-nigra)
has been identified as a focal species of management concern due to more than a 50% population decline during the 1950's to 1990's on the northern Alaska, western Alaska, and Canadian breeding grounds. The Pacific Common Eider is the most distinct subspecies, morphologically and genetically, of the 4 subspecies recognized in North America. It breeds primarily along the coastal fringe of Alaska, western Canada and far eastern Russia, and winters at sea in ice-free waters of eastern Russia, southwestern Alaska, the Aleutian Islands and Kodiak Island. Information on natural history and limiting factors for this subspecies is lacking for some areas, particularly for molt and wintering grounds. The North American population of this subspecies is estimated to be 170,000, but long-term trends for this subspecies are largely unknown for areas outside Alaska and the western Canadian Arctic. Although the cause of sharp population declines is not clear, factors thought to be contributing to Pacific Common Eider declines include accumulation of heavy metals in the food chain, oil pollution, introduced predators in nesting grounds, and harvest of adults, eggs and down for subsistence.
Date: June 2010
Sources:
Sea Duck Joint Venture Management Board. 2008. Sea Duck Joint Venture Strategic Plan 2008 - 2012. USFWS, Anchorage, Alaska; CWS, Sackville, New Brunswick. 95 pp.
USFWS. 2006. Action plan for the Pacific common eider. U.S. Fish and Wildlife Service, Anchorage, Alaska. Unpublished. report. 55Pp. + appendices.
Species Profile from NatureServe (*information only at the species level*)
Common Eider Somateria mollissima
Description:A sea duck (eider).
Life History:
Reproduction Comments: Nests late April-early July (Maine); begins nesting mid- to late June in Beaufort Sea area (Johnson and Herter 1989). Clutch size averages 3-5. Incubation 24-30 days, by female (male departs); female relies on endogenous energy reserves during incubation. Eggs hatch mainly mid- to late July (sometimes into August) in arctic of Alaska and Canada. Young are led to water soon after hatching, tended by female, soon join young of other broods, independent at 60-75 days (fledging reported as occurring at 6-12.5 weeks). Female first breeds at 2-3 years, generally not until at least 3 years old. Rarely renests if clutch is lost, unless loss occurs during laying or early incubation. Nest success 15-70% (Bellrose 1980). In the Atlantic Flyway, duckling survival generally is low, sometimes due to gull predation. Commonly nests in loose aggregations or colonies (usually a few dozen pairs, but up to several thousand pairs in some areas). Intraspecific nest parasitism may be relatively common (Condor 94:871-879).
Ecology Comments:
Predation by herring gull and great black-backed gull causes most nesting failures on islands in Maine, but eider nesting success may be enhanced in nests close to gull colony (gulls defend area against other avian pradators). Arctic fox sometimes an important predator on nesters in Alaska. Ravens, raccoons, and mink sometimes destroy nests. Annual survivorship of adult generally is relatively high, with sport hunting likely the major cause of mortality in the Atlantic flyway (Kehoe 1994).
Habitat:
Marine Habitat(s): Near shore
Estuarine Habitat(s): Bay/sound, Herbaceous wetland, Lagoon, River mouth/tidal river
Palustrine Habitat(s): Riparian
Terrestrial Habitat(s): Tundra
Habitat Comments: NON-BREEDING: rocky seacoasts, bays, estuaries. Rests on rocks, sandbars, ice. In winter in the Gulf of St. Lawrence, concentrated in areas with shallow water reefs and high prey density (Guillemette et al. 1993). BREEDING: Nests on the ground in grass or brush, usually close to salt water, often on island or rocky headland or along shore of pond or lagoon. Nests usually on small island (often less than 5 ha in Maine) or spit. Nests often concealed by plants (forest, shrub, or herbaceous), rocks, logs, driftwood. Often nests in same site in successive years. See Blumton et al. (1988) for habitat suitability index model.
Distribution:
United States:
AK, MA, MD, ME, MI, NC, NH, NJ, NY, RI, SC, SD, VA
NatureServe Status:
Global Status: G5,
Global Status Last Reviewed: 28Nov2000,
Global Status Last Changed: 28Nov2000,
Rounded Global Status: G5 - Secure
Reasons:
Large geographic range, with many well-separated large sub-populations, and legal restrictions in most countries on perceived threats, suggest little immediate threat to species. Apparently declining in western Canadian Arctic.
Other Statuses:
IUCN Red List Category: LC - Least concern
