Golden-winged warbler

The Golden-winged warbler (Vermivora chrysoptera) is a New World warbler. It breeds in southeastern and south-central Canada and in the Appalachian Mountains in northeastern to north-central United States. The majority (~70%) of the global population breeds in Wisconsin, Minnesota, and Manitoba. Golden-winged warbler populations are slowly expanding northwards, but are generally declining across its range, most likely as a result of habitat loss and competition/interbreeding with the very closely related Blue-winged warbler, Vermivora cyanoptera. The genus name Vermivora is from Latin vermis 'worm', and vorare, 'to devour', and the specific chrysoptera is from Ancient Greek khrusos, 'gold', and pteron, 'wing'. This is a small warbler, measuring 11.6 cm (4.6 in) long and weighing 8–10 g (0.28–0.35 oz). The male has black throat, black ear patch bordered in white, and a yellow crown and wing patch. Females appear similar to males, with a light gray throat and light gray ear patches. In both sexes, extensive white on the tail is conspicuous from below. Underparts are grayish white and the bill is long and slender. Unlike most warblers, juveniles can be reliably sexed (using throat patch color) approximately 15 days after fledging. Golden-winged warblers are migratory, breeding in eastern North America and wintering in southern Central America and the neighboring regions in Colombia, Venezuela, and Ecuador. They are very rare vagrants elsewhere.