Morphology ³

Harlequin ducks are between 35.6-50.8cm/14-20in and weigh 0.45-0.68kgs. Males have blue-grey bodies with chestnut flanks and distinctive white patches on the head and body. These white patches are outlined with black. In flight males show white on their wings with a metallic blue speculum. Females are dusky brown with two or three whitish patches on the sides of the face. Females do not have any white on their wings in flight and do not have a speculum. However, when this species molts it is hard to distinguish between males and females.

Habitat and ecology ⁴

This species is found breeding on swifts torrents and rapid streams of rugged uplands, normally wintering on rocky coastlines. It feeds mainly on insects and their larvae in summer, catching molluscs and crustaceans in winter. Feeding mostly occurs mostly by diving, but also dabbling and head-dipping in shallow water. Breeding begins in May or June, nesting on the ground concealed in vegetation (del Hoyo et al. 1992).

Conservation status ⁵

Harlequin ducks are not endangered currently. At one point they were considered threatened on the Atlantic coastline. These ducks are susceptible to oil spills, since they spend most of their time in the water, and high mortality has resulted from previous oil spills. For example, Alaskan harlequin ducks were still exhibiting reduced survival rates as a result of the 1989 Exxon Valdez oil spill as late as 1998. Logging is a significant threat in the state of Washington because it removes suitable forests along the streams that these ducks use during the breeding season. Also, logging causes silt build up in streams, reducing the amount of prey available.

Sources and Credits

1. (c) Jim Johnson, some rights reserved (CC BY-NC-ND), uploaded by Jim Johnson
2. (c) Soheil Zendeh, some rights reserved (CC BY-NC-SA), http://lh4.ggpht.com/-0mLI1nz5J60/T7nU-UiVVGI/AAAAAAAAMFQ/f9guLRMvEBU/harlequin.ducks.DSCN4015.jpg
3. (c) The Regents of the University of Michigan and its licensors, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/31398357
4. Adapted by Yukon Conservation Data Centre from a work by (c) International Union for Conservation of Nature and Natural Resources, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/31085371
5. (c) The Regents of the University of Michigan and its licensors, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/31398366

More Info

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