The harlequin duck (Histrionicus histrionicus) is a small sea duck. It takes its name from Harlequin (Italian Arlecchino, French Arlequin), a colourfully dressed character in Commedia dell'arte. The species name comes from the Latin word , meaning "actor". Other names include painted duck, totem pole duck, rock duck, glacier duck, mountain duck, white-eyed diver, squeaker, lords and ladies and blue streak.

Taxonomy

In 1747 the English naturalist George Edwards included an illustration and a description of the harlequin duck in the second volume of his A Natural History of Uncommon Birds. He used the English name "The Dusky and Spotted Duck". Edwards based his hand-coloured etching on a preserved specimen that had been brought to London from Newfoundland in eastern Canada. When in 1758 the Swedish naturalist Carl Linnaeus updated his Systema Naturae for the tenth edition, he placed the harlequin duck with the ducks, geese and swans in the genus Anas.

Linnaeus included a brief description, coined the binomial name Anas histrionica and cited Edwards' work. The harlequin duck is now the only extant species placed in the genus Histrionicus that was introduced in 1828 by the French naturalist René Lesson. The species is monotypic: no subspecies are recognised.

thumb|A pair of harlequin ducks, hen (left) and drake (right)

Two prehistoric harlequin ducks have been described from fossils, although both were initially placed in distinct genera: Histrionicus shotwelli is known from Middle to Late Miocene deposits of Oregon, United States and was considered to form a distinct monotypic genus, Ocyplonessa. Histrionicus ceruttii, which lived in California during the Late Pliocene, was at first taken to be a species of the related genus Melanitta.

Description

left|thumb|Harlequin hen

thumb|left|Adult drake

Adult breeding males have a colorful and complex plumage pattern. The head and neck are dark slate blue with a large white crescent marking in front of the eye that extends up to the crest, a small round dot behind the eye, and a larger oval spot down the side of the neck. A black crown stripe runs over the top of the head, with chestnut patches on either side. A black-bordered white collar separates the head from the breast. The body is largely a lighter slate blue with chestnut sides. A black-bordered white bar divides the breast vertically from the sides. The tail is black, long and pointed. The speculum is metallic blue. The inner secondary feathers are white and form white markings over the back when folded. The bill is blue-grey and the eye is reddish. Adult females are less colourful, with brownish-grey plumage with three white patches on the head: a round spot behind the eye, a larger patch from the eye to the bill and a small spot above the eye.

Both female and male harlequins exercise mate choice preference and pair-bond defense, to demonstrate fidelity to their partner. Either partner is able to divorce the pair-bond to pursue a higher-quality option, however this behavior is uncommon.

References

  • Toughest of Birds, Dressed Up as a Clown article at Smithsonian Migratory Bird Center
  • Harlequin Duck Species Account – Cornell Lab of Ornithology
  • Harlequin Duck - Histrionicus histrionicus - USGS Patuxent Bird Identification InfoCenter
  • eNature.com – Harlequin Duck
  • Harlequin Duck Population Monitoring in the Strait of Georgia, British Columbia
  • Harlequin Duck, Histrionicus histrionicus at Canada's Polar Life (University of Guelph)
  • Harlequin Duck: Wildlife Notebook Series from Alaska Department of Fish and Game