Fairly dull warbler, constantly bobs its tail. Often low in vegetation, or on the ground. Plumage varies in brightness, but always shows rufous cap, pale eyebrow, and some brown streaks on breast. Forages for insects in a variety of shrubby and open habitats. Breeds in bogs and clearings in the boreal forest. One of the more common warblers wintering in the southern U.S. Also winters in the Caribbean and Yucatan Peninsula. Two populations: "Western" is browner, "Yellow" has brighter underparts.