Editing Common eider (section)

==Description==
[[File:Common Eider (Somateria mollissima) skull at the Royal Veterinary College anatomy museum.JPG|thumb|A common eider skull]]
[[File:Somateria mollissima MWNH 1023.JPG|thumb|Egg, Collection [[Museum Wiesbaden]]]]

The common eider is both the largest of the four [[eider]] species and the largest [[duck]] found in Europe, and is exceeded in North America only by smatterings of the [[Muscovy duck]], which only reaches North America in a wild state in southernmost Texas (and arguably south Florida where feral but non-native populations reside). It measures {{convert|50|to|71|cm|in|frac=2|abbr=on}} in length, weighs {{convert|0.81|to|3.04|kg|lboz|frac=2|abbr=on}} and spans {{convert|80|-|110|cm|in|abbr=on}} across the wings.<ref name=AAB/><ref name=Ogilvie2004/> The average weight of 22 males in the [[North Atlantic]] was {{convert|2.21|kg|lboz|frac=2|abbr=on}} while 32 females weighed an average of {{convert|1.92|kg|lboz|frac=2|abbr=on}}.<ref name=CRC/> It 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. The drake's display call is a strange almost human-like "ah-ooo", while the hen utters hoarse quacks. 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 colour. Some authorities place the subspecies ''v-nigra'' as a separate species.

This species dives for crustaceans and molluscs, with [[mussel]]s being a favoured food. The eider will eat mussels by swallowing them whole; the shells are then crushed in their [[gizzard]] and excreted. When eating a crab, the eider will remove all of its claws and legs, and then eat the body in a similar fashion.

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 ([[Handbook of the Birds of the World|HBW]]).

A particularly famous colony of eiders lives on the [[Farne Islands]] in [[Northumberland]], [[England]]. These birds were the subject of one of the first ever bird protection laws, established by [[Cuthbert of Lindisfarne|Saint Cuthbert]] in the year 676.<ref name = "Waltho"/> 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".

In Canada's Hudson Bay, important eider die-offs were observed in the 1990s by local populations due to quickly changing ice flow patterns. The Canadian Wildlife Service has spent several years gathering up-to-date information on their populations, and preliminary results seem to show a population recovery.<ref name=seaduckjv/><ref name=Henri2012/><ref name=Chaulk2012/> The common eider is the object of the 2011 documentary ''[[People of a Feather]]'',{{Citation needed|date=June 2024}} which studies the historical relationship between the [[Sanikiluaq]] community and eiders, as well as various aspects of their ecology.<ref name=peopleofafeather/>

The common eider is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds ([[AEWA]]) applies.