Brown Thrashers spend most of their time on ground level or near it. When seen, it is commonly the males that are singing from unadorned branches. The brown thrasher has been noted for having an aggressive behavior, and is a staunch defender of its nest. However, the name does not come from attacking perceived threats, but is believed to have come from the thrashing sound the bird makes when digging through ground debris. It is also thought that the name comes from the thrashing sound that is made while it is smashing large insects to kill and eventually eat.
This species appears remarkably big-headed, especially if it puffs up the small crest. Its plumage is gray-brown above. It has a white throat, dirty gray breast and buffish underparts which become whiter during the breeding season. Two indistinct buff bars are present on each wing. Its lack of an eye ring and wingbars, and its all dark bill distinguish it from other North American tyrant flycatchers, and it pumps its tail up and down like other phoebes when perching on a branch. The eastern phoebe’s call is a sharp chip, and the song, from which it gets its name, is fee-bee.