According to the Cornell Lab of Ornithology website's "The Birds of North America Online" (2009), the Townsend’s Warbler (Dendroica townsendi) was among the many species first collected by John Kirk Townsend during his expedition with Thomas Nuttall through the Rocky Mountains to the Pacific Coast in 1834. The description of Townsend’s Warbler (male only) first appeared in the Journal of the Academy of Natural Sciences of Philadelphia" in 1837, written by Thomas Nuttall under John Kirk Townsend’s name (see passage below). The first specimen seems to have been procured in the forests along the Columbia River near Fort Vancouver, Washington.

John Kirk Townsend, 1836, Description of Twelve New Species of Birds, chiefly from the vicinity of the Columbia river, IN: Journal of the Academy of Natural Sciences of Philadelphia, 1837, Vol.II, Part II: "Sylvia Townsendi, (Nuttall.), Townsend's Warbler. Description. Colour bright olive-green, spotted with black; head, cheeks, throat and breast, black; flanks spotted with black; line over the eye a broad diverging one beneath to the shoulder and belly, yellow; rump, two banks on the wings, and the inner webs of the three lateral tail feathers on each side, almost wholly white. The female of this species is unknown. Inhabits the shady forests of the Columbia river, where it probably breeds."