Common Eider
From Wikipedia, the free encyclopedia
| Common Eider | ||||||||||||||
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 Adult drake
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| Binomial name | ||||||||||||||
| Somateria mollissima (Linnaeus, 1758) |
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 Green: breeding
Blue: winter/feeding |
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(European Eider)
(Faeroe Eider)
(North Pacific Eider)
(North Atlantic Eider)
(Hudson Bay Eider)
(American Eider) |
The Common Eider, Somateria mollissima, is a large (50-71cm body length) sea-duck, which is distributed over the northern coasts of Europe, North America and eastern Siberia. It breeds in Arctic and some northern temperate regions, but winters somewhat farther south in temperate zones, when it can form large flocks on coastal waters.
The eider's nest is built close to the sea and is lined with the celebrated eiderdown, plucked from the female's breast. This soft and warm lining has long been harvested for filling pillows and quilts, but in more recent years has been largely replaced by down from domestic farm-geese and synthetic alternatives. Although true Eiderdown pillows or quilts are now a rarity, eiderdown harvesting continues and is sustainable, as it can be done after the ducklings leave the nest with no harm to the birds.
The Common Eider is characterized by its bulky shape and large wedge-shaped bill. The male is unmistakable with its black and white plumage and green nape. The female is a brown bird, but can still be readily distinguished from all ducks, except other eider-species, on the basis of size and head shape. This duck's call is a pleasant "ah-ooo." The species is often readily approachable.
Drakes of the European, eastern North American and Asia/western North American races can be distinguished by minor differences in plumage and bill color.
This species dives for crustaceans and molluscs, with mussels being a favored food.
It is abundant, with populations of about 1.5-2 million birds in both North America and Europe, and also large but unknown numbers in eastern Siberia (HBW).
A particularly famous colony of eiders lives on the Farne Islands in Northumberland, Britain. These birds were the subject of one of the first ever bird protection laws, established by Saint Cuthbert in the year 676. About 1,000 pairs still nest there every year. Because St. Cuthbert is the patron saint of Northumberland, it was natural that the eider should be chosen as the county's emblem bird; the birds are still often called Cuddy's ducks in the area, "Cuddy" being the familiar form of "Cuthbert".
The Common Eider is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA) applies.
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[edit] Social behaviour
Eiders are colonial breeders. They nest on coastal islands in colonies ranging in size of less than 100 to upwards of 10,000-15,000 individuals [2]. Female eiders frequently exhibit a high degree of natal philopatry, where they return to breed on the same island where they were hatched. This can lead to a high degree of relatedness between individuals nesting on the same island, as well as the development of kin-based female social structures [3]. This relatedness has likely played a role in the evolution of co-operative breeding behaviours amongst eiders. Examples of these behaviours include: laying eggs in the nests of related individuals [4] and crèching, where female eiders team up and share the work of rearing ducklings [5].
[edit] Gallery
 Adult male left, female right |
 Adult male in eclipse plumage |
 Male first winter plumage. Note how similar this is to the adult eclipse plumage. |
 Female |
[edit] References
- ^ BirdLife International (2004). Somateria mollissima. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 11 May 2006. Database entry includes justification for why this species is of least concern
- ^ Chapdelaine, G., P. Dupuis and A. Reed. 1986a. Distribution, abondance at fluctuation des populations d’eider à duvet dans l’estuaire et le golfe du Saint-Laurent. Pp. 6–19 in Eider ducks in Canada (A. Reed, ed.). Canadian Wildlife Service Report Series no. 47, Ottawa, ON.
- ^ McKinnon, L., H. G. Gilchrist, and K. T. Scribner. 2006. Genetic evidence for kin-based female social structure in common eiders (Somateria mollissima). Behavioral Ecology 17:614-621.
- ^ Andersson, M. and P. Waldeck. 2007. Host-parasite kinship in a female-philopatric bird population: evidence from relatedness trend analysis. Molecular Ecology 16:2797-2806.
- ^ Öst, Markus, Colin W. Clark, Mikael Kilpi, and Ron Ydenberg, "Parental effort and reproductive skew in coalitions of brood-rearing female common eiders." The American Naturalist: January 2007
- Scientific discussion about recent hunting regulations on Greenland
[edit] External links
- Cornell Lab of Ornithology-Common Eider
- Massachusetts Breeding Bird Atlas-Common Eider
- Common Eider videos on the Internet Bird Collection
