The Chestnut-Sided Warbler is mostly white, with a bright yellow cap, black eye stripe and moustache, chestnut sides and flanks, and streaked wings and back. The female is similar but less boldly colored. Unlike many warblers, the immature and fall birds are easy to identify. Both are a distinctive lime-green above with a white eye ring. The Chesnut-Sided Warbler is one of the easiest warblers to identify. Besides its unmistakable plumage, this warbler is fairly tame and allows close approach while feeding and nesting. The Chesnut-Sided Warbler generally forages at low to medium heights in the forest, where it probes the undersides of leaves.

Diet: Insects

Range: The Chestnut-Sided Warbler went through a massive range expansion due to extensive logging in the 1800's, which created suitable habitat. It now breeds throughout southern Canada (west to Alberta), the Great Lakes states, New England, and the Appalachian Mountains. These warblers winter in Mexico, the West Indies, Central America. and northern South America.

Habitat: The Chestnut-Sided Warbler breeds in early successional deciduous woodlands with substantial undergrowth.