Species: Dendroica townsendi

Animalia - Craniata - Aves - Passeriformes - Parulidae - Dendroica - No subspecies are currently recognized. Although considered monotypic, morphological differences suggest two distinct subspecies (Grinnell 1905, Morrison 1983). The population that winters in Oregon and California can be separated from the population wintering in Mexico and Central America by wing length; although these populations formally satisfy the designation as subspecies, they have not been formally designated as such (Morrison 1983, Pogson et al. 1997). Grinnell (1905) found that the population wintering along the Pacific Coast and breeding in Southeast Alaska and coastal British Columbia had shorter wing chords than birds wintering from northern Mexico to Costa Rica and breeding in the interior western United States. Morrison (1983) found a similar pattern, but he grouped specimens from Southeast Alaska with longer-winged birds wintering south of the United States.