Heteronetta atricapilla
The Black-headed Duck (Heteronetta atricapilla) is a unique, medium-sized duck, measuring approximately 35-38 cm (14-15 in) in length and weighing between 430-660 g (15-23 oz). Males are strikingly characterized by a glossy black head, a black back, and flanks that contrast with a pale, buffy belly and white undertail coverts; their bill is short, stout, and dark grey. Females are duller, primarily brownish-grey with a darker cap and back, and a paler throat and belly. A distinctive field mar...
This duck primarily inhabits shallow freshwater wetlands, including marshes, ponds, lakes, and slow-moving rivers, particularly those with dense emergent vegetation. It prefers low to moderate elevations across its South American range.
Their diet primarily consists of aquatic invertebrates, such as insect larvae and small crustaceans, supplemented with seeds and vegetative parts of aquatic plants. They forage by dabbling at the surface or performing short dives to retrieve food from the bottom.
Black-headed Ducks are generally diurnal, spending their days foraging and often remaining secretive within dense cover, particularly the females. They are adept at both dabbling at the surface and diving for food, frequently feeding in shallow waters where they can reach the bottom. Unlike most ...
The Black-headed Duck is endemic to South America, with its primary breeding and year-round range extending across central and northern Argentina, Uruguay, Paraguay, and parts of southern Brazil. Its distribution also reaches into central Chile, Bolivia, and rarely into southeastern Peru. Populat...
Least Concern
- The Black-headed Duck is the only known obligate brood parasitic duck in the world, never building its own nest or raising its young. - Females lay their eggs in the nests of over 100 different host species, including various ducks, coots, gulls, and even raptors. - Its eggs have unusually thic...