Common eider

Somateria mollissima

Eider eend / Eiderente / Eider à duve

Eiders are large seaducks in the genus Somateria, distributed over the northern coasts of Europe, North America and eastern Siberia. It breeds in Arctic and some northern temperate regions, but winterssomewhat farther south in temperate zones, when it can form large flocks on coastal waters.

The Common eider has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend is not known, but the population is not believed to be decreasing sufficiently rapidly to approach the thresholds under the population trend criterion (>30% decline over ten years or three generations). The population size is extremely large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern (IUCN, 2009).

The global population of Somateria mollissima (including v-nigra) is estimated to number c.3,100,000-3,800,000 individuals (Wetlands International 2006), while the population in Russia has been estimated at c.10,000-100,000 breeding pairs and c.1,000-10,000 wintering individuals (Brazil 2009).

Subspecies and Distribution

Drakes of the European, eastern North American and Asia/western North American races can be distinguished by minor differences in plumage and bill colour. Now, six subspecies are recognized.

Above: subspecies of the common eider. Click the image to enlarge.

• S. m. mollissima (Linnaeus, 1758) – Common Eider – breeds from NW Europe E to Novaya Zemlya; winters S to Atlantic coast of France and N Mediterranean Basin.
• S. m. faeroeensis C. L. Brehm, 1831 – Faeroe Is, Shetland Is and Orkney Is, and Outer Hebrides (W Scotland).
• S. m. borealis (C. L. Brehm, 1824) – breeds in Arctic Atlantic from Groswater Bay (Labrador) N to Southampton I and Baffin I, E through Greenland and Iceland to Franz Josef Land; in winter, around coasts of N Atlantic, reaching Gulf of St Lawrence.
• S. m. sedentaria Snyder, 1941 – Hudson Bay and James Bay region.
• S. m. dresseri Sharpe, 1871 – breeds in NE North America from Groswater Bay (Labrador) S to Massachusetts; in winter from Gulf of St Lawrence S to Long I, New York.
• S. m. v-nigrum Bonaparte & G. R. Gray, 1855 – Pacific Eider – New Siberian Is (NE Siberia) E to NW North America; winters Bering Sea and Aleutian Is.

Source: http://www.hbw.com/species/common-eider-somateria-mollissima

Above: comparison of lower mandible and throat of Pacific eider (left) and European eider (right).

Above: Somateria mollissima mollissima, adult male (breeding plumage)

Above: Somateria mollissima mollissima, adult male (breeding plumage)

Above: Somateria mollissima mollissima, adult female

Above: Somateria mollissima mollissima, adult couple (breeding plumage)

Above: Somateria mollissima dresseri, adult male (breeding plumage)

Above: Somateria mollissima dresseri, adult female (breeding)

Above: Somateria mollissima dresseri, adult birds (breeding plumage)

Above: Somateria mollissima borealis, adult birds (breeding plumage)

Above: Somateria mollissima faeroensis, adult male (end of eclipse plumage)

Above: Somateria mollissima faeroensis, adult female

Above: Somateria mollissima faeroensis, adult female

Above: Somateria mollissima faeroensis, adult male (breeding plumage)

Above: Somateria mollissima faeroensis, adult male (eclipse plumage)

Above: Pacific eiders, Somateria mollissima v-nigrum (breeding plumage)

Above: Pacific eiders, Somateria mollissima v-nigrum (breeding plumage)

Above: Pacific eiders, Somateria mollissima v-nigrum (breeding plumage)

Above: male Pacific eider, Somateria mollissima v-nigrum (breeding plumage)

Above: male Pacific eider, Somateria mollissima v-nigrum (breeding plumage)

Above: common eider ducklings