Physical characteristics

The Parulidae is a vast group, yet the wood warblers share a number of traits. Most have slender or flat beaks that are pointy, but short. Some wood warblers, like the yellow-breasted chat (Icteria virens) and yellow-rumped warbler, have

A Connecticut warbler (Oporornis agilis) in flight. (Photo by Doug Wech-sler/VIREO. Reproduced by permission.)

more robust bills, while the American redstart (Setophaga ru-ticitta) sports distinctive rictal bristles, which are stiff, modified feathers at the base of its flat bill. Most wood warblers are small birds, tending toward the smaller side of the family's 4-7.5 in (10.2-19.1 cm) range. They are characterized by legs that look no more sturdy than a toothpick, and have the typical three-toes-forward foot structure of other birds in the Passeriformes order.

Wood warbler plumage ranges widely in color. These "jewels of the forest" generally have yellow, red, black, gray, or green areas of plumage, with yellow and olive the predominant colors within the family. Males of the temperate species are usually much brighter in color and have sharper patterns than do the females, but males of some species become duller and resemble the females in fall and winter. Juvenal plumage is frequently similar to the female's, but duller still. Among the more tropical species, the males and females generally look alike. In some species of wood warbler, like the yellow warbler (Dendroica petechia), the male is slightly larger than the female. A unifying trait among all wood warblers is the presence of nine functional primary feathers. Other songbirds typically have 10.

Another identifying feature of many wood warblers is their seemingly constant movement. They flit from branch to branch, usually giving observers only a quick glimpse of color before they fly off to another spot. A birder can spend hours in the field listening to a common yellowthroat (Geothlypis trichas) or yellow warbler singing nearby, but may be unable to focus the binoculars on anything more than a branch left swaying by the bird that just left.

Finally, one of the most distinguishing characteristics of the wood warblers is their songs, which add greatly to na ture's symphony. Prime examples include the Louisiana wa-terthrush (Seiurus motacilla), an insignificant-looking ground dweller that often utters its loud, pleasant tune to a background of rushing water; and the yellow-breasted chat, which has a loud, flutelike and gurgling song. The ovenbird (Seiu-rus aurocapillus) is much less melodious, with a blunt cry that sounds like "teacher, teacher." In contrast, the feeble "heee-bsss" song of the blue-winged warbler sounds like an insect and is often identified as such by inexperienced human observers.

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