Scientific name: Aythya marila (Linnaeus, 1761)
Bird group: Ducks
Field characters. 42-51 cm. At a distance male appears black at front and back and white in the middle. Head, shoulders, breast, upper- and undertail black; back vermiculated pale grey, flanks and underparts white. Bill and legs blue-grey. Differs from somewhat smaller male Tufted Duck by grey back and absence of crest. Male in eclipse is duller, but much more resembles male summer than adult female. Female like female Tufted Duck but with whitish patch on ear-coverts and large whitish patch at base of bill; in winter with broad, white band around base of bill. Juvenile as adult female in winter but white band around bill narrower or absent on forehead.
Voice. Silent. During the breeding season male produces rapid series of soft, low whistles; female has a deep, harsh "karr-karr-karr".
Distribution. Fairly common breeding bird in the most northern parts of the region.
Habitat. In the breeding season, occurs on lakes, lochs and pools in tundra, and wooded tundra zones. Outside the breeding season numerous birds concentrate on mainly marine or low salinity waters such as landlocked seas, bays and mouths of estuaries, but the species may also winter on large freshwater lakes.
Food. Omnivorous, gregarious, and day-time feeder which obtains food by diving up to 6 m. Takes mostly molluscs, and to a lesser extent crustaceans, insects, and annelids.
Eggs. Unmarked, ground colour greenish/olive-grey. Texture not glossy. Shape subelliptical. Size 62x43 mm (55-68 x 41-48), weight 61 g (53-71) for eggs laid in captivity. Eggs in appearance very much like Common Pochard, but smaller.