Common Eider
Somateria mollissima
The common eider is the largest of the four eider species, measuring 50 to 71 cm (19+1⁄2 to 28 in) in length, weighs 0.81 to 3.04 kg (1 lb 12+1⁄2 oz to 6 lb 11 oz) and spans 80–110 cm (31–43 in) across the wings. The average weight of 22 males in the North Atlantic was 2.21 kg (4 lb 14 oz) while 32 females weighed an average of 1.92 kg (4 lb 3+1⁄2 oz). It is distinguished by its bulky shape and large, wedge-shaped bill. The male is distinct, with its black and white plumage and green nape.
ID text from Wikipedia, CC BY-SA 4.0
King Eider
Somateria spectabilis
The king eider is a large sea duck, measuring 50–70 cm (20–28 in) in length with a wingspan of 86–102 cm (34–40 in). Males are, on average, heavier than females, with a mean weight of 1.668 kg (3.68 lb) for males and 1.567 kg (3.45 lb) for females. An individual bird's mass can vary considerably from season to season—from as little as 0.9 kg (2.0 lb) to as much as 2.2 kg (4.9 lb). Like all eiders, the species is sexually dimorphic; the male is slightly larger and, in breeding plumage, much more colourful than the female. Voice: The male's song is a quavering, dove-like cooing, transcribed as croo-croo-croo or hoo-hoo-hooo. The female makes a variety of low clucks, grunts and growls.
ID text from Wikipedia, CC BY-SA 4.0
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