COMMON MERGANSER

COMMON MERGANSER(Mergus merganser)

The Common merganser is a fairly large diving duck at around 70 cm (27 in.) long, and prefers fresh over saltwater habitats. The drake is mostly white with a black head with green iridescence. The head has a crest but in the male it is usually not visible. The wings are with except the first upper half, which is black. The tail is grey, the bill red with a dark, down-curved tip. Females are mostly grey with a red-brownish head and white under parts, and the crest is visible. The legs are red in both sexes. Juveniles are similar to the female but lack the head crest.

The Latin genus name ‘mergus’ refers to a water bird, and ‘merganser’ is a contraction of ‘mergus’ and ‘anser’, the latter meaning ‘goose’. Actually this duck is also called ‘goosander’ in Europe and Asia.

The summer habitat of the common merganser encompasses rivers and lakes in the boreal forest of the Northern hemisphere. This duck is a partial migrant, and will move south of its summer range where it can find ice-free bodies of water in the winter.

Common mergansers build their nests in tree holes in the forest, but also use other structures such as chimneys, nest boxes, even holes in the ground. Females can lay up to 17 eggs.

This duck will eat fish and aquatic insects and crustaceans. The bill has serrated edges to help hold fish.

The common merganser breeds on PEI, however this has ‘never been confirmed’ as per the Maritime Breeding Bird Atlas. It is however common around the island, and ‘very common’ in the fall and winter.

Conservation: Although the population numbers of the common merganser has declined markedly in the last few decades, this duck does not yet appear on any list of threatened species. Possible factors for the decline may include pesticides and other pollutants in their environment, and hunting. This duck is also targeted by anglers because of its diet, which includes commercially valuable fish such as trout and salmon.

Common merganser pair - Vaxholm, Sweden - photo by Bengt Nyman
Common merganser pair – Vaxholm, Sweden – photo by Bengt Nyman
Common Mergansers - Bridgetown, PEI - Feb. 18, 2013 - Joanne Dunphy
Common Mergansers – Bridgetown, PEI – Feb. 18, 2013 – © Joanne Dunphy
Common merganser female - Las Gallinas Wildlife Ponds, San Rafael, CA - photo by Frank Schulenburg
Common merganser, female – Las Gallinas Wildlife Ponds, San Rafael, CA – photo by Frank Schulenburg
Common Merganser, female - North Lake, PEI - Mar. 19, 2014 - © Joanne Dunphy
Common Merganser, female – North Lake, PEI – Mar. 19, 2014 – © Joanne Dunphy
Common Mergansers in flight - Indian River area, PEI - Mar. 26, 2018 - Chris Rice
Common Mergansers in flight – Indian River area, PEI – Mar. 26, 2018 – Chris Rice
Common Merganser taking off - Feb. 15, 2018 - Roberta Palmer
Common Merganser taking off – Feb. 15, 2018 – Roberta Palmer