Family New World Warblers (Parulidae)

Least Concern

Black-throated Blue Warbler (Setophaga caerulescens)


French: Paruline bleue German: Blaurücken-Waldsänger Spanish: Reinita azulada

Motacilla caerulescens

J. F. Gmelin

, 1789,

Santo Domingo, Dominican Republic


One record of hybridization, probably with S. petechia. Validity of race cairnsi has been questioned, both by earlier ornithologists and by more recent ones, on the basis that, in males at least, differences from nominate are not constant (cairnsi-type males occur in nominate population, and vice versa); further research required. Two subspecies tentatively recognized.

Subspecies and Distribution
  • S. c. caerulescens (J. F. Gmelin, 1789) – S Canada from Saskatchewan (irregular) and S Ontario E to Nova Scotia and in NE USA from Minnesota E to New England; migrates to Caribbean (mainly Bahamas and Greater Antilles), small numbers to E Central America.
  • S. c. cairnsi (Coues, 1897) – E USA in Appalachians from SW Pennsylvania S to N Georgia; migrates to Caribbean, some to E Central America.
  • Descriptive notes

    12–14 cm; 8·4–12·4 g. Male nominate race has dark blue crown, nape and upperparts, black throat and face, white underparts with broad black streak... read more


    Most common song (possibly Type 1) a series of 3–5 (usually four) buzzy, drawn-out notes, the... read more


    Breeds in mature deciduous or mixed forest with well-developed understorey, also in old logged... read more

    Food and feeding

    Feeds mainly on insects and other arthropods; also some seeds, fruit and nectar in winter. In one study, lepidopteran larvae comprised 60... read more


    Season May–Aug, egg-laying May–Jul (occasionally into Aug); sometimes double-brooded. Polygyny recorded, and in recent study... read more


    Migratory, moving medium to long distance. Leaves breeding grounds in late Aug and early Sept,... read more

    Status and conservation

    Not globally threatened (Least Concern). Generally common throughout its range. Numbers are thought to be stable, though there have been some local decreases at the edges of... read more

    Recommended citation

    Curson, J. (2019). Black-throated Blue Warbler (Setophaga caerulescens). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from on 6 December 2019).