Family New World Blackbirds (Icteridae)

Least Concern

Giant Cowbird (Molothrus oryzivorus)


French: Vacher géant German: Riesenkuhstärling Spanish: Tordo gigante

O[riolus]. oryzivorus

J. F. Gmelin

, 1788,

Cayenne, French Guiana


Formerly placed in genus Psomocolax or Scaphidura, but such treatment not supported by molecular work. Geographical variation weak; further study desirable. Race impacifus commonly emended to “impacificus” but there is no justification for this under the International Code of Zoological Nomenclature. Two subspecies tentatively recognized.

Subspecies and Distribution
  • M. o. impacifus (J. L. Peters, 1929) – E Mexico (Veracruz) S to W Panama.
  • M. o. oryzivorus (J. F. Gmelin, 1788) – C Panama E to Colombia, S on Pacific coast to NW Peru (Tumbes), and from Venezuela, Trinidad and Tobago and the Guianas S to E Peru, Bolivia, N & NE Argentina (Jujuy, Salta and N Corrientes) and most of Brazil (S to Santa Catarina; absent in NE).
  • Descriptive notes

    Male 34 cm, 174–242 g; female 29 cm, 144–167 g. A large, long-winged and long-tailed black interid, erectile feathers around neck forming ruff; in its undulating... read more


    Rather silent. Song usually a high-pitched, shrill whistle followed by a warble “psee-... read more


    In breeding season often near colonies of Psarocolius and Cacicus at forest edge... read more

    Food and feeding

    Insects and other invertebrates, and seeds; sometimes takes nectar from brush-shaped inflorescences of Combretum vines. In NE... read more


    Season Apr–Nov in Panama, Dec–Apr in Suriname and Sept–Dec in NE Argentina. Brood parasite mostly on colonial species of... read more


    Apparently resident. Probably some short-distance movements between breeding and non-breeding... read more

    Status and conservation

    Not globally threatened. Uncommon to fairly common or locally common; widespread. Rare or absent from several states of NE Brazil; scarce and local in llanos of R... read more

    Recommended citation

    Fraga, R. (2019). Giant Cowbird (Molothrus oryzivorus). 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 11 December 2019).