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Giant Cowbird - BirdForum Opus

Male. Photo by Robert_Scanlon
Panama, January 2004
Molothrus oryzivorus

Scaphidura oryzivora


  • Overall black with purplish shine
  • Neck ruff conspicuous giving a pigeon-breasted (chest heavy) or small-headed appearance
  • Bill large, robust and black
  • Male iris colour varies. It is reddish in Mexico and most of Central America becoming more yellow as one goes east in Panama.

Males and females are very similar. Females are smaller, duller (less glossy) and with a pale yellowish eye; male eye is reddish.


From Mexico in Southern North America through Central America and South America to Argentina and Bolivia



There are 2 subspecies[1]:

  • M. o. impacifus:
  • Caribbean slope of southern Mexico (southern Veracruz) to western Panama
  • M. o. oryzivorus:


Semiopen to open areas like forest clearings, wooded savannahs, fields, etc, but usually near colonies of nest hosts.



Feeds mainly on the ground but also observed feeding on larger mammals (eating biting flies and similar) and occasionally by gleaning from leaves


Nest parasite which mainly deposit eggs in nests of Oropendolas and Caciques, but also described as parasitizing a couple of Jay species and a couple of large orioles.


  1. Clements, J. F., T. S. Schulenberg, M. J. Iliff, B.L. Sullivan, C. L. Wood, and D. Roberson. 2013. The eBird/Clements checklist of birds of the world: Version 6.8., with updates to August 2013. Downloaded from http://www.birds.cornell.edu/clementschecklist/download/
  2. Neotropical birds online

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