The black-throated blue warbler is a small passerine bird of the New World warbler family. Its breeding ranges are located in the interior of deciduous and mixed coniferous forests in eastern North America. Over the cooler months, it migrates to islands in the Caribbean and Central America. It is very rarely found in western Europe, where it is considered to be a non-indigenous species. The black-throated blue warbler is sexually dimorphic; the adult male has a black face and cheeks, deep blue upperparts and white underparts, while the adult female is olive-brown above and light yellow below.
Region
Eastern North America, the Caribbean, and Central America
Typical Environment
Breeds in the interior of mature deciduous and mixed coniferous-deciduous forests of the northeastern United States and southeastern Canada, with strong concentrations in the Appalachians. During migration it moves through the eastern U.S., especially along the Atlantic and Gulf coasts. Winters primarily in the Greater Antilles and parts of the northern Caribbean, with some individuals reaching Central America. Prefers dense understory and mid-story layers in breeding habitat and shaded broadleaf forests in winter. Occasionally recorded as a vagrant in western Europe.
Altitude Range
0–2000 m
Climate Zone
Temperate
Ease of Keeping
Beginner friendly: 1/5
Males show a striking white "handkerchief" patch at the base of the primaries, a key field mark even at a distance. Females look very different—olive-brown with a subtle pale eyebrow and a smaller pale wing patch—making this species a classic example of strong sexual dimorphism. They nest low in dense understory shrubs, and are faithful to quality forest habitat. On the wintering grounds they often join mixed-species flocks in shaded broadleaf forests and shade-coffee plantations.
Female foraging for termites at the John Heinz National Wildlife Refuge
Male at the Pinery Provincial Park
Typical nest site
Temperament
solitary and territorial
Flight Pattern
short rapid wingbeats
Social Behavior
Breeding males defend compact territories in dense understory where the female builds a cup nest low in shrubs or small saplings. Pairs are typically monogamous within a season, and both parents feed the nestlings. Outside the breeding season they often join mixed-species foraging flocks and show site fidelity to high-quality winter habitat.
Migratory Pattern
Seasonal migrant
Song Description
The male sings a buzzy, rising series of notes often rendered as zee-zee-zee-zree with a distinctive final accent. Calls include a sharp, dry tsip used in contact and alarm contexts.
