Saturday, May 26, 2012

>>Genus Polysticta >Polysticta stelleri (Steller's Eider)

Steller's Eider


Steller's Eider
A drake
Conservation status

Vulnerable (IUCN 3.1)
Scientific classification
Kingdom:Animalia
Phylum:Chordata
Class:Aves
Order:Anseriformes
Family:Anatidae
Subfamily:Merginae
Genus:Polysticta
Eyton, 1836
Species:P. stelleri
Binomial name
Polysticta stelleri
(Pallas, 1769)
The Steller's Eider (Polysticta stelleri) is a medium-large sea duck that breeds along the Arctic coasts of eastern Siberia and Alaska. The lined nest is built on tundra close to the sea, and 6-10 eggs are laid.
It winters somewhat farther south in the Bering Sea, northern Scandinavia and the Baltic Sea. It can form large flocks, up to 200,000 birds on suitable coastal waters. It is scarce south of its wintering range.
This species dives for crustaceans and molluscs, with mussels being a favoured food.
This species is the smallest eider. The male is unmistakable with its black upperparts and neck collar, white head and yellowish underparts. The drake's call is a deep crooning, although it is relatively quiet compared to the Somateria eiders.
The female is a dark brown bird, smaller with a more typically duck-shaped head and body than other eider species. She also has a repertoire of grunts and whistles.
This bird is named after the German naturalist Georg Steller.
The Steller's Eider is thought to have hybridised with the Common Eider on at least two occasions in the wild. A drake showing characters of both species was present at Cuxhaven, Niedersachen,Germany on 17 November 1993. Another drake was seen in Vadso harbour, Varanger, Norway on 7 April 1995; a photograph of this bird was published accompanying Forsman (1995).

Conservation

The Steller's Eider is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA) applies. There is an active recovery plan in Alaska.

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