Warblers

The American warblers are small, brightly colored, insectivorous birds. Most species of American warblers are resident in tropical forests, but some migrate to northern ecosystems to breed.

At least 52 species of American warblers breed north of Mexico. Some of these species have very wide ranges, occurring over much of the United States and Canada. The yellow warbler (Dendroica petechia), for example, is a common species found in shrubby habitats from the northern low arctic through all but the southernmost deciduous forests and western deserts. The common yellowthroat (Geothlypis trichas) is similarly widespread in marshes and shrubby habitats, from the subarctic through the southern states and into Mexico. The yellow-breasted chat (Icteria virens) is the largest species of warbler in North America, with a body length of 15 in (38 cm). This species also ranges widely, from southern Canada through most of the United States. The yellow-rumped warbler (Dendroica coronata) is one of the most familiar species, because it breeds in many types of conifer forests, and winters throughout much of the southern United States and down into Mexico and elsewhere in Central America.

Male birds of these and many of the other North American warblers are very colorful. The prothonotary or golden swamp warbler (Protonotaria citrea) occurs in hardwood swamps and riparian forests, and has a brilliant yellow plumage, offset by its gray-blue wings. The northern parula (Parula americana) occurs in eastern hardwood forests, and has a bright blue back, and a yellow breast with a black-and-red band running across. The male blackburnian warbler (Dendroica fusca) of eastern spruce-fir forests has an orange throat framed by black and white markings. The red-faced warbler (Cardellina rubrifrons) of southern Arizona and Mexico has a crimson face and throat. The American redstart (Setophaga ruticilla) is a widespread forest species with a black body and bright, orange patches on its flanks and tail.

American warblers are a diverse component of the community of birds breeding in most forests of the Americas. In some places in North America, 10 or more species may breed in the same stand. Although all of these birds feed on small arthropods, they segregate ecologically by feeding in different parts of the tree canopy, on the surface of tree bark, or on the forest floor.

A male black-throated green warbler (Dendroica virens) at Metropolitan Beach Metropark, Michigan. Usually found high in trees, this warbler was in the grass feeding on grounded insects after a cold snap. Photograph by Robert J. Huffman. Field Mark Publications. Reproduced by permission.