A small (4 ½ -5 inches) wood warbler, the male Black-throated Green Warbler is most easily identified by its olive back, black breast and throat, and yellow face. Female Black-throated Green Warblers are similar to males, but are duller and lack much of the black on the breast and throat. The male is relatively unmistakable in good light, while the female may be distinguished from other greenish-yellow female wood warblers by its tell-tale combination of yellow face and olive back. The Black-throated Green Warbler primarily breeds in south-central Canada and the northeastern United States. Smaller numbers breed at higher elevations in the Appalachian and Ozark Mountains as far south as Alabama and Arkansas. The Black-throated Green Warbler winters from south Florida and Texas south to northern South America. Black-throated Green Warblers breed in a number of woodland habitat types, particularly those primarily composed of evergreen trees. In winter, this species is mainly found in humid tropical forests. Cape May Warblers mainly eat small invertebrates, including insects and spiders, although this species may eat fruits or berries in winter. In appropriate habitat, Black-throated Green Warblers may be observed foraging for food located on leaves, needles, and branches in the forest canopy. Birdwatchers may also listen for this species’ song, a buzzing “zoo zee” repeated several times in succession. Black-throated Green Warblers are primarily active during the day, but, like many migratory songbirds, this species migrates at night.