Scientific name: Histrionicus histrionicus (Linnaeus, 1758)
Bird group: Ducks
Field characters. 38-45 cm. A small, very dark duck with a short bill. Plumage of male dark grey-blue (appears black at a distance) with chestnut-brown flanks and pattern of white patches and stripes on head, neck, and breast; stern black with white patch on sides. In flight male has a short white wing-bar and white braces; bill lead-blue. Female dull blackish-brown with mottled whitish lower breast and belly, two whitish patches in front of eye and one on ear-coverts; bill dark slate-blue. Juvenile as adult female but upperparts paler.
Voice. Male produces a low, piping whistle starting with two separate notes and ending in descending trill; female has a harsh croack; generally silent.
Distribution. Breeds only on Iceland; fairly common.
Habitat. In the breeding season it is confined to continuously turbulent waters such as streams, rapids, and waterfalls. Winters on coasts.
Food. Takes animal prey off rocks after surface-dive with partially opened wings. Food items in winter are molluscs, crustaceans, and, to a lesser extent, annelids and fish. During summer it takes insect larvae, crustaceans, waterbeetles, small fish.
Eggs. Unmarked; ground colour creamy-yellow/yellow white. Texture smooth, slightly glossy. Shape long subelliptical/short subelliptical. Size 58 x 41 mm (50-62 x 39-43), weight 53 g.