Other Names: none
Distribution: throughout Canada and mountainous regions of the western United States in summer; south through Mexico and central America in winter.
Size: 11-12 cm in length with a 15-17 cm wingspan.
Plumage: Adult males are olive green above and yellow below, with a black crown patch. Most females and all juveniles lack the black crown and may be distinguished from other olive green warblers with yellow underparts by the complete lack of wing bars, streaks, tail spots, or other markings. The beak is gray, the legs are pinkish-gray, and the eyes are black.