- 13–21.3 in
- 22–26 in
- 17.6–25.6 oz
- Arlequin plongeur, Canard arlequin, Canne de roche (French)
- More than half of eastern North American population of Harlequin Ducks winters in coastal Maine, particularly outer reaches of Penobscot and Jericho bays.
- When engaged in behavioral interactions, the Harlequin Duck gives distinctly unducklike squeaks, the source of one of its local names: sea mouse.
Mountain streams and rivers, usually in forested regions; in winter, primarily turbulent coastal waters, especially in rocky regions.
Insects, fish, and marine invertebrates.
- Clutch Size
- 3–9 eggs
- Egg Description
- Pale creamy to pale buff.
- Condition at Hatching
- Covered in down and able to leave the nest soon after hatching.
Dives for prey on or near bottom.
Wintering populations in eastern North America are currently much smaller than historical (late 1800s) numbers, but populations grew in the last part of 20th century. Listed as "Endangered" in Canada and "Threatened" in Maine. A "species of special concern" in western states.
- Robertson, G. J., and R. I. Goudie. 1999. Harlequin Duck (Histrionicus histrionicus). In The Birds of North America, No. 466 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.