Scientific Name: Histrionicus histrionicus Common Name: Harlequin duck Class, Order, and Family: Class Aves, Order Anseriformes, Family Anatidae, Subfamily Anatinae.

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Description: The Harlequin duck is a medium-sized diving duck that breeds on fast-flowing streams and winters along rocky coastlines. It is a small, relatively uncommon sea duck with a white patch in front of its eyes and round white spot near its ear. The male’s body plumage is dark slate-blue with reddish-brown sides and white bands, patches, and spots. The female is dusky brown with two or three round white spots on her head. The male is boldly marked whereas the female is mostly dark brown with some white spots on the head. The duck’s squeak is distinctively mouse-like. These ducks are 33-54 cm in size, with a wingspan of 56-66 cm, and a weight of 500-726 g (an average of less than 700 g for males and 600 g for females).

Habitat: The Harlequin duck is found along mountain streams and rivers, usually in forested regions. More than half the eastern North American population winters in coastal Maine, specifically the turbulent coastal waters and rocky regions in the outer reaches of Penobscot and Jericho Bays. 

Summer Range: The Harlequin duck spends its summers in regions from Alaska to northwestern Wyoming, and from northern Quebec and Labrador to northern New Brunswick. In the summer it is also found in Greenland, Iceland, and Siberia.

Winter Range This duck winters along rocky coastlines with crashing surf. For example, the Pacific Coast from Alaska to northern California, and along the Atlantic Coast from Newfoundland to New Jersey. In the winter, it is also found in Greenland, Iceland, along the Pacific Coast, and southward to Japan.

Food: The Harlequin duck eats insects, fish, and marine invertebrates.
During the spring and summer, the Harlequin duck will forage for food and dive for prey on, or near, the bottom of freshwater stream beds searching for the larvae of blackflies, caddis flies, stone flies, and midges.

In the winter, these ducks locate their food by diving in shallow waters to find and pry prey (including small crabs, amphipods, gastropods, limpets, chitons, blue mussels, and fish eggs) from crevices.

Breeding Behaviour: This duck breeds on fast-flowing streams. It leaves the salt water in the spring to breed. They usually breed for the first time at two or three years of age. Little is known about courtship behaviour, although breeding normally begins in late May or early June.

Nest Type and Egg Description: Nests are usually located near fast-moving streams on the ground, in tree cavities, or in bank overhangs. Females may use the same site in consecutive breeding seasons. Nests are lined with down, and hens will lay eggs in early summer at intervals of two to four days.

The eggs are pale creamy to pale buff in colour, and the clutch size is three to nine. The eggs are incubated by the hen, which only rarely leaves the nest to feed, wash or rest for 28 or 29 days until they hatch. Ducklings are covered in down and are able to leave the nest soon after hatching.

Conservation Status: Harlequin duck wintering populations in eastern North America are much smaller than they were in the late 1800s, however populations have grown in the latter part of the 20th century. Currently, Harlequin ducks are listed as “endangered” in Canada, “threatened” in Maine, and as a “species of special concern” in some western states.

Harlequin populations have low reproductive rates because of the late age of first breeding, small average clutch size, and the high number of non-breeding birds within the populations.

The Harlequin duck has been protected in Canada as a migratory game bird since 1917, when the Migratory Birds Convention Act became law. In 1990, a complete ban on hunting Harlequin ducks began in eastern Canada.

Information on this page compiled by Colleen Sutton.

Sources
BirdLife International. http://www.birdlife.org
Committee on the Status of Endangered Wildlife in Canada. http://www.cosewic.gc.ca/eng/sct5/index_e.cfm
Cornell Lab of Ornithology. All About Birds. http://www.birds.cornell.edu/AllAboutBirds/.
Ehrlich, Paul R. 1988. The Birder’s Handbook. Simon and Schuster, New York.
Godfrey, Earl W. 1986. Birds of Canada. National Museums of Canada, Ottawa.
Hinterland Who’s Who. http://www.hww.ca
Leslie, Scott. 2006. Wetland Birds of North America. Key Porter Books, Toronto. NatureServe. InfoNatura. http://www.natureserve.org/infonatura/

Atlantic Coastal Islands