the lincoln's sparrow , melospiza lincolnii , is a medium-sized sparrow .
adults have dark-streaked olive-brown upperparts with a light brown breast with fine streaks , a white belly , and a white throat .
they have a brown cap with a grey stripe in the middle , olive-brown wings , and a narrow tail .
their face is grey with brown cheeks , a brown line through the eye , and an eye ring .
they are somewhat similar in appearance to the song sparrow .
their breeding habitat is wet thickets or shrubby bogs across canada , alaska , and the northeastern and western united states; this bird is less common in the eastern parts of its range .
the nest is a well-concealed shallow open cup on the ground under vegetation .
these birds migrate to the southern united states , mexico , and northern central america; they are passage migrants over much of the united states , except in the west .
they forage on the ground in dense vegetation , mainly eating insects and seeds .
they are very secretive .
their song is a musical trill , but this bird is often not seen or heard even where they are common .
this bird was named by audubon after his friend , thomas lincoln , of dennysville , maine .
lincoln shot the bird on a trip with audubon to nova scotia in 1834, and audubon named it "tom's finch" in his honor .
