Common Merganser

Overview

The common merganser, or goosander, is a large sea duck of rivers and lakes in forested areas of Europe, Asia, and North America. It is classed as Least Concern on the IUCN Red List.

Identification

• 58–72 cm long with a 78–97 cm wingspan, weighing between 0.9 and 2.1 kg.
• Adult males in breeding plumage have a black head with an iridescent green sheen, a white body with a variable salmon-pink tinge, and grey rump and tail.
• Females and males in non-breeding plumage are largely grey with a reddish-brown head and white chin.
• The bill and legs are red to brownish-red, with the colour being brightest on adult males.

Habitat

The species lives in rivers and lakes, typically within forested areas of Europe, Asia, and North America, and is equally at home in salt and fresh water. It requires mature forest for breeding to find tree cavities, although in treeless areas such as the mountains of Central Asia, it uses holes in cliffs and steep, high banks.

Diet

It eats mainly fish but also takes a wide range of other aquatic prey, including molluscs, crustaceans, worms, insect larvae, and amphibians. It uses serrated edges on its bill to grip prey and often fishes in groups by forming a semicircle to drive fish into shallow water.

Did you know?

Males that breed in Western Europe migrate north to estuaries in Finnmark in northern Norway to moult, leaving the females to care for the ducklings.