The Common Pochard (Aythya ferina) is a powerful diving duck whose rust-brown male appears almost like a living block of rust riding the lake surface during the breeding season. It is robust and medium-sized, with a sloping forehead and raised nape giving a dove-like profile that separates it from the Tufted Duck, and in flight shows a broad, pale wingband along the entire underwing. It measures 42–49 cm in length, has a wingspan of 72–82 cm and weighs 700–1,200 grams. The male shows a strongly rust-brown head and neck, black breast and rear end, silver-grey flanks with fine vermiculation, a red-orange iris, and a pale blue bill with a black tip and base. The female is brown with a diffuse, pale eye-band and paler throat, resembling a female Tufted Duck but lacking that species' white patch at the bill base.
The male's courtship call is a low, soft "whee-ooh," a creaking whistle heard in April and May, while the female gives a harder, rasping "karrr" or "kack"; outside the display period the species is generally quiet. In Sweden it breeds mainly in the south and centre, most densely around Mälaren, Hjälmaren and Vättern and the large Skåne lakes, favouring shallow, eutrophic lakes with rich submerged vegetation and dense reed cover for nesting. The nest is a deep bowl of dry grass and reed lined with down, and the female lays 7–11 unmarked, green-grey eggs, incubating alone for 24–28 days; brood parasitism is common, with females laying eggs in each other's nests, and chicks dive from their first day, fledging at around 50–55 days. The diet is mainly aquatic plants obtained by diving, supplemented by molluscs and insect larvae when feeding chicks. With only around 1,000 breeding pairs left, the population has declined sharply since the 1990s through the loss of shallow lakes to overgrowth and eutrophication, and the species is now classed Vulnerable (VU) globally and Endangered (EN) in Sweden.
Read about this species in Swedish →