21-7-2024 ISAFJORDUR, ICELAND - COMMON EIDER (JUVENILE) (Somateria mollissima)

The common eider is a large diving duck that is easily distinguishable, even at quite long distances, because of the elongated profile of the head. Adults of this species are approximately 58 cm long and weigh from 1.2–2.8 kg.

Males and females have very different plumage; the male has a black crown, belly and tail, while the rest of the plumage is white, the breast usually has a pinkish tinge. Males also have characteristic green marks on the sides of the head. The female is brown with light, closely packed bars over the whole body.

Young males are a mottled brown-black and white, the pattern of which varies with age. Young birds are difficult to distinguish from adult males in transitional plumage after the nesting season, when they are switching to their winter colours.

The male’s voice is a deep, prolonged ‘coo-roo-uh’, the female’s call is a growling ‘cor-r-r’.