New World Blackbirds (Icteridae)

Brown-headed Cowbird (Molothrus ater) - HBW 16, p. 786

French: Vacher à tête brune German: Braunkopf-Kuhstärling Spanish: Tordo Cabecipardo
Other common names: Common Cowbird

Taxonomy: Oriolus ater Boddaert, 1783, Carolina, USA.
Closely related to M. bonariensis, and much resembling it in habits, general behaviour and voice. Race obscurus intergrades with artemisiae in Sierra Nevada (California). Proposed race californicus, described from L Buena Vista (Kern County), in SC California, is subsumed in obscurus. Three subspecies recognized.

Subspecies and Distribution:

  • obscurus (J. F. Gmelin, 1789) - breeds along Pacific seaboard from S Alaska S (E to the Cascades and Sierra Nevada) to NW & N Mexico (N Baja California, also on mainland S to Oaxaca); N populations migrate to S parts of breeding range, in Mexico extending to S Baja Califonia.
  • artemisiae Grinnell, 1909 - breeds from W Canada (interior British Columbia E to SC Manitoba) S in W USA (E from the Cascades and Sierra Nevada) to California, Nevada and New Mexico; migrates S to Mexico (S to Michoacán).
  • ater (Boddaert, 1783) - breeds from SE Canada (S Ontario E to Newfoundland) S throughout E USA to C Texas, Gulf Coast and C Florida, and in E Mexico S to Tamaulipas; winters in Florida and in Mexico S to Oaxaca.