Common Merganser

The common merganser, or goosander, is a large duck of rivers and lakes in forested areas of Europe, Asia and North America, and it eats mainly fish. It is 58–72 cm long with a wingspan of 78–97 cm and weighs 0.9–2.1 kg. Breeding males are easily told by a white body with a variable salmon-pink tinge, a black head with an iridescent green sheen, a grey rump and tail, and wings largely white on the inner half; females and eclipse males are largely grey with a reddish-brown head and white chin (Wikipedia, general species account).

It nests in holes in trees, the female laying 6–17 white to yellowish eggs, most often 8–12, and raising one brood a season. Birds often fish in a group, forming a semicircle and driving fish into shallows where they are easier to catch. SoIB 2023 treats it as a winter migrant and localised summer migrant of wetlands, rates it a High conservation priority, and gives a rapid long-term decline of about 74% and a current decline of nearly 8% a year (Wikipedia, general species account; SoIB 2023).