Common Eider

How to recognise it

• Long wedge-shaped bill forming a straight line with the forehead
• Breeding male is white with black crown, pinkish-red breast and pale green nape patch
• Female is rusty grey and brown with black barring, speculum edged by two white bars
• In flight, note the heavy body, thick short neck and striking head shape

Call and song

The Common Eider is vocal during the breeding season. The male has a soft, far-carrying call, "a-ooh-å". The female cackles "gak-ak-ak-ak...", a sound likened to a distant fishing boat.

Where and when

The Common Eider is a partial migrant that breeds commonly along Sweden's sea coasts, and the largest Swedish population is in the Stockholm archipelago. It is reported all year round, and its share of all bird reports is highest in Halland, Blekinge and Gotland. The Swedish Red List 2025 classes it as Endangered (EN), and it has declined sharply, probably because of thiamine deficiency.

Food and behaviour

It feeds on crustaceans and molluscs, and mussels are its most important food. Mussels are swallowed whole and the shells crushed in the gizzard. It dives for food down to 20 metres or picks it from the bottom in shallow water. To take off it first runs along the water surface to gain speed. In winter it often stays out on the open sea in large flocks.