Editing Common eider (section)

{{short description|Species of bird}}
{{Speciesbox
| name = Common eider
| image = Пухівка на Кінбурнській косі.jpg
| image_caption = Adult male, breeding plumage
| image2 = Common eider female at Jones Beach (04713).jpg
| image2_caption = Female
| status = NT
| status_system = IUCN3.1
| status_ref = <ref name="iucn status 12 November 2021">{{cite iucn |author=BirdLife International |date=2018 |title=''Somateria mollissima'' |volume=2018 |page=e.T22680405A132525971 |doi=10.2305/IUCN.UK.2018-2.RLTS.T22680405A132525971.en |access-date=12 November 2021}}</ref>
| genus = Somateria
| species = mollissima
| authority = ([[Carl Linnaeus|Linnaeus]], [[10th edition of Systema Naturae|1758]])
| subdivision_ranks = Subspecies
| subdivision = * ''S. m. mollissima'' <small>([[Carl Linnaeus|Linnaeus]], [[10th edition of Systema Naturae|1758]])</small>
* ''S. m. faeroeensis'' <small>[[Christian Ludwig Brehm|C. L. Brehm]], 1831</small>
* ''S. m. v-nigra'' <small>[[Charles Lucien Bonaparte|Bonaparte]] and [[George Robert Gray|G. R. Gray]], 1855</small>
* ''S. m. borealis'' <small>([[Christian Ludwig Brehm|C. L. Brehm]], 1824)</small>
* ''S. m. sedentaria'' <small>Snyder, 1941</small>
* ''S. m. dresseri'' <small>[[Richard Bowdler Sharpe|Sharpe]], 187FF99551</small>
| range_map = Somateria mollissima map.svg

| range_map_caption = Range of ''S. mollissima'' {{leftlegend|#FF9955|Breeding range|outline=gray}}{{leftlegend|#87AADE|Wintering/Feeding range|outline=gray}}

| synonyms = ''Anas mollissima'' {{small|Linnaeus,&nbsp;1758}}
}}
[[File:Baltsende eiders-4961556.webm|right|thumb|Common eiders (Somateria mollissima) in the breeding season on Texel, the Netherlands.]]
The '''common eider''' (pronounced {{IPAc-en|'|ai|.|d|@r}}) ('''''Somateria mollissima'''''), also called '''St. Cuthbert's duck''' or '''Cuddy's duck''', is a large ({{cvt|50|–|71|cm}} in body length) [[Merginae|sea-duck]] that is distributed over the northern coasts of [[Europe]], [[North America]] and eastern [[Siberia]]. It breeds in [[Arctic]] and some northern temperate regions, but [[bird migration|winters]] somewhat farther south in [[temperate]] zones, when it can form large flocks on coastal waters. It can fly at speeds up to {{cvt|113|km/h}}.<ref name=birds-speed/>

The eider's nest is built close to the sea and is lined with [[down feather|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 eiderdown pillows or quilts are now a rarity—typically being marketed as [[luxury goods]]—eiderdown harvesting continues and is sustainable, as it can be done after the ducklings leave the nest with no harm to the birds.