Family Ducks, Geese, Swans (Anatidae)

Least Concern

American Comb Duck (Sarkidiornis sylvicola)


French: Canard sylvicole German: Höckerschnabelente Spanish: Pato crestudo americano
Other common names: Comb Duck, Black-sided Comb Duck

Sarkidiornis sylvicola

H. von Ihering and R. von Ihering

, 1907,

Iguapé, São Paulo, Brazil, and Buenos Aires; Argentina


Usually treated as a race of S. melanotos. Occasional treatment as full species (most recently in a 2005 monograph#R) justifiable on basis of slightly smaller size (mean male wing 336 vs 360, mean male bill 56 vs 62) (allow 1); glossy blackish-grey vs matt greyish-white flanks (3); glossy blackish-grey vs matt greyish-white back and rump (extension of flanks, but notable in flight and wing-flapping; score 1); fully developed comb proportionately different, rising more at right angles from forehead and usually curving over more smoothly, forming disc-shape more than sail-shape, whereas in melanotos it rises at a forward angle in a longer straight line, curving at apex more sharply, so that surface area is larger and leading edge forms a longer vertical (2). Studies of voice and behaviour to supplement these distinctions needed. Proposed race carunculatus is invalid. Monotypic.


Tropical South America from Colombia, Venezuela and the Guianas S to N Argentina and Uruguay. Rare breeder in E Panama.

Descriptive notes

55–63 cm; 1069–1863 g. Unmistakable, although fleshy knob of male is smaller outside breeding season, when yellow wash to head also lost. Female smaller without knob over... read more


Generally rather silent. Vocalizations probably very similar to those of S. sylvicola, but... read more


Freshwater swamps, rivers and their deltas, lakes, rice fields, inundated floodplains, all with... read more

Food and feeding

Diet based on vegetable matter, mostly seeds of grasses, sedges and aquatic plants, grain and rice, complemented with terrestrial and... read more


Breeding data almost non-existent, with even seasonality being poorly known, although in Brazil dependent young have been observed with... read more


Mainly sedentary, with seasonal (perhaps even sometimes nomadic) movements mostly related to... read more

Status and conservation

Not globally threatened (Least Concern). CITES II. Widespread and locally common. S. sylvicola has been proposed for Near Threatened status by Threatened Waterfowl... read more

Recommended citation

del Hoyo, J., Collar, N. & Kirwan, G.M. (2019). American Comb Duck (Sarkidiornis sylvicola). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from on 14 December 2019).