Red-breasted merganser

Mergus serrator

Group: Waterfowl
Size class: Small (under 10 kg)
Family: Anatidae

Range

North America
Europe

Habitat

Coast

Range

Countries it is found in

64 countries

Åland Islands
Albania
Armenia
Austria
Azerbaijan
Bahamas
Belgium
Bermuda
Bosnia & Herzegovina
Bulgaria
Canada
China
Colombia
Croatia
Cuba
Czechia
Denmark
Estonia
Faroe Islands
Finland
France
Georgia
Germany
Greece

Range from:Wikipedia country bird lists, GBIF occurrence records — read 2026-08-05

Chapter 01

Overview

The red-breasted merganser (Mergus serrator) breeds across much of the temperate to subarctic Northern Hemisphere and winters mostly on the coast, making it the Mergus species most at home on salt water. The epithet serrator is Latin for 'sawyer', after the saw-like edge of its bill. The red breast that names it is worn only by males in breeding plumage. The world population is stable and the IUCN rates it least concern, though European numbers have fallen by up to 30 per cent over three generations.

Chapter 02

Identification

51–64 cm long with a 66–74 cm wingspan; males weigh 950–1,350 g and females 800–1,100 g. It has a spiky crest and a long, thin red bill with serrated edges. The drake has a dark head glossed green, a white neck, a rusty breast, a black back and white underparts. Females have a rusty head and greyish-brown body. They are easily confused with female goosanders, which show more contrast between dark head and pale breast and a pale chin patch the red-breasted lacks.

Chapter 03

Behaviour

It feeds by diving from the surface after small shoaling fish, gripping them with its serrated bill, and also takes crustaceans, worms and insects. It nests on the ground in sheltered spots within about 25 m of a lake, river or sheltered bay, often on islets. The female lays eight to ten eggs on average and incubates them for about 30 days; the young leave the nest within a day. Males leave the breeding grounds in June to moult at the coast, and outside the breeding season the birds form flocks.

Chapter 04

Hunting

In North America it is a game bird under the Migratory Bird Treaty and may be hunted in set seasons and places, though few hunters are interested and relatively few are taken. It is also hunted in Denmark. Anglers and fish farmers persecute it as a competitor, illegally so in Britain, especially Scotland. In Sweden the småskrake has no general open season in the hunting ordinance.

Sources

Sources: Red-breasted merganser — Wikipedia, Småskrake — Wikipedia (svenska), Jaktförordning (1987:905) — Sveriges riksdag — read 2026-10-29

Cross-reference