Wilson's warbler (Cardellina pusilla) is named after ornithologist Alexander Wilson, who first noted the bird in 1811. Wilson, who born in Scotland, is regarded as the greatest American ornithologist prior to Audubon. The male Wilson's warbler has a distinct black cap, which makes it easy to identify from the similar yellow warbler (see, Yellow Warbler). Greenish above and yellow below, with rounded wings and a long, slim tail, it's a warbler that often flips its longish tail as it hops in bushes or on branches. Wilson's warbler breeds in northern Canada and the western US.
