Location in Oregon
Blue is Winter range - Red is Summer range
Purple is Year-round range - Yellow is Migration range

Wilson's Warbler

Wilsonia pusilla - Fairly common in thickets, especially in willows. The male is recognized by the glossy black cap, the female by the plain bright yellow underparts, lack of tail spots, and yellow forehead. Song is of 15-20 musical chips, dropping slightly in pitch towards the end, 5-10/min.