Black-throated Blue Warbler
Setophaga caerulescens
BTBW

Bird Description
Fairly common in deciduous woods, usually in damp areas under the canopy. In late fall often eats pokeberries. Song a slow buzzy ‘zi zee zee zee zee’ (‘I am so lay-zee’). Call a hard ‘tek,’ junco-like. Tends to move slowly and often just appears at head height. ID: A fairly large and robust, neckless warbler. Young birds are essentially the same as respective-sex adults. All have white square patch at base of primaries, reduced in younger birds, particularly ♀. This is striking in flight, showing as a wing bar on already pale underwing. Ad ♂: striking black around face and flanks contrasting with blue upperparts and white underparts. 1styr ♂: green tips to upperparts, sometimes pale flecking in throat. Southern/Appalachian population can show dark mantle streaking and lack green in youngsters. Ad ♀: dull green above, dirty buff below. Always look for distinctive face pattern: dark ear covers set off by pale border with pale eyelid. Pale base to primaries can be hidden or nearly absent, but diagnostic when present.
