Screaming Cowbird Molothrus rufoaxillaris

  • Order: Passeriformes
  • Family: Icteridae
  • Monotypic
  • Authors: Peter E. Lowther


  • Year-round
  • Migration
  • Breeding
  • Non-Breeding
Distribution of the Screaming Cowbird
eBird range map for Screaming Cowbird

Generated from eBird observations (Year-Round, 1900-present)

Distribution in the Americas

Resident in extreme southern Brazil (Rio Grande do Sul), Uruguay (Maldonado, Lazcano, Rio Negro, Flores, Canelones, Santa Helena, San Vicente), Paraguay (Chaco Bernalcué), northern Argentina (Salta, Tucuman, Catamarca, La Rioja, Formosa, Santa Fé, Corrientes, south to Córdoba and Buenos Aires) and extreme southeastern Bolivia (Caiza, Bolivian Chaco; Hellmayr 1937, Pinto 1944, Blake 1968).

Primarily occurs in the lowlands, but locally (?) up to 1000 m (Ridgely and Tudor 1989, Parker et al. 1996).

Distribution outside the Americas

Endemic to the Americas.


Common in cultivated and bushy parts of Salta region of Argentina (Hoy and Ottow 1964). Found in pastures, fields, scrubby, weedy areas and around towns (Ridgely and Tudor 1989).

Historical changes

Range expanding northeastwards into southeastern Brazil in 1980s (Willis and Oniki 1985).

Fossil history

No known records.

Recommended Citation

Lowther, P. E. (2011). Screaming Cowbird (Molothrus rufoaxillaris), version 1.0. In Neotropical Birds Online (T. S. Schulenberg, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA.