Scientific name: Aythya nyroca (Guldenstadt, 1770)
Bird group: Ducks
Field characters. 38-42 cm. Somewhat smaller and more delicate than Tufted Duck. Male with rich chestnut head, neck, and breast; sides and flanks paler; upperparts black-brown and wings glossed dull green; conspicuous white undertail; belly and eye white, legs black; bill slate-grey with grey tip and edges. In flight with conspicuous, broad white band along whole length of hind wing. Female duller and browner than male and with brown eyes. Juvenile very similar to adult female but with brown spots on undertail-coverts. Male in eclipse also as adult female but eye still white.
Voice. Generally silent; male has a low, grating wheeze; note of female like female Pochard but less loud.
Distribution. Local and rare breeding bird in Europe.
Habitat. Prefers secluded pools and lagoons rich in submerged and floating vegetation and fringed by dense stands of emergent plants.
Food. Feeding methods include surface-feeding, swimming with head submerged, up-ending, and diving. Mainly seeds and other parts of aquatic plants; it takes also small fish, tadpoles, annelids, molluscs, insects, crustaceans.
Eggs. Unmarked; ground colour pale buff/pale brown. Texture smooth, not glossy. Shape subelliptical/short subelliptical. Size 53 x 38 mm (48-60 x 35-43), weight 36 g (31-41) for eggs laid in captivity. Eggs of this species are distinctly smaller than other Aythya species.