The male indigo bunting is commonly seen as a breeding species and at migration hot spots. In the spring, the Indigo may be present in large flocks, particularly during migratory fallouts, and is often seen in brushy habitat or along weedy margins of fields and roads, where it sits up and twitches its tail. It sometimes hybridizes with the lazuli bunting. Monotypic. Length 5.5".
Highly sexually dimorphic. Summer male: plumage unmistakable, entirely bright blue. Winter male: blue obscured by brown and buff edging; mottled brown and blue early in winter. Summer female: dull brown, usually with 2 faint wing bars and indistinct streaking on underparts. Whitish throat, small conical bill with straight culmen, relatively long primary projection. Immature and winter female: