the tennessee warbler (oreothlypis peregrina) is a new world warbler that breeds in eastern north america and winters in southern central america and northern south america .
the tennessee warbler is 11.5 cm (4.5 in) long , has a 19.69 cm (7.75 in) wingspan , and weighs roughly 10 g (0.35 oz) .
the breeding male has olive back , shoulders , rump and vent .
the flight feathers are brownish-black .
it has a slate gray neck , crown and eyeline .
the underside is a gray-white .
the female is similar to the male , but is much duller and has a greener tinge to the underside .
the tennessee warbler has long wings , short tail and a thin , pointy bill .
juveniles and first-year birds are quite similar to the female .
tennessee warblers resemble female black-throated blue warblers .
the only difference is that the black-throated blue has a darker cheek and two white wing spots .
this bird can be confused with the red-eyed vireo , which is larger , moves more deliberately and sings almost constantly .
the orange-crowned warbler can also look similar , but lacks the white eyebrow , is greyer-brown above and has yellow undertail coverts .
it breeds from the adirondack mountains in new york through northern vermont , new hampshire , and maine north and west throughout much of canada .
it is also found breeding in northeast minnesota and northern upper peninsula of michigan .
it is migratory , wintering in southern central america and northern colombia and venezuela , with a few stragglers going as far south as ecuador .
it is a very rare vagrant to western europe .
this bird was named from a specimen collected in tennessee , where it may appear during migration .
the tennessee warbler feeds mainly on insects and prefers the spruce budworm .
this species fluctuates in population with the quantity of the budworm .
it also likes flower nectar , fruit and some seeds .
this warbler , like most others , is nervous and quick while foraging .
it creeps along branches and is found at all levels .
it is solitary while nesting , but forms mixed flocks after breeding .
the tennessee warbler prefers coniferous forests , mixed conifer-deciduous forests , early successional woodlands and boreal bogs .
it makes a cup-shaped nest of dried grasses and moss lined with finer grasses , stems and hair .
the nest can be placed on the ground or above a bog in moss or in the base of a shrub .
the nest is built by the female , and she lays 47 white eggs with brown splotches on them .
