Bay-breasted Warbler (Setophaga castanea) appears more sluggish in foraging than do other warblers feeding in the same spruce forest. Its diet mostly consists of insects and berries. During the breeding season, the bird eats a variety of insects, including beetles, flies, moths, caterpillars, leafhoppers, and grasshoppers. In winter in the tropics, it forages for berries. Both parents feed the nestlings.
Distribution & Habitat
The Bay-breasted Warbler is found in woodlands and conifers. Usually, it breeds in northern coniferous forests, in thick stands of spruce and fir. Where spruce is not found, the species will nest in deciduous and mixed second-growth woods or birches, maples, firs, and pines.
- In winter, it moves to the tropics and is seen in forest edge, second growth, and open woodland.
- In spring, this species moves north through Central America and then flies north across the Gulf of Mexico, continuing to Canada and the northeast.
- In fall, it moves south on the border front.
The Bay-breasted Warbler is fairly common; its numbers vary from year to year and are likely to increase quickly during population explosion of the spruce budworm or other forest pests. It could be vulnerable to loss of habitats on wintering grounds.