Many warblers winter in South and Central America, and migrate through the United States late in the spring. In May, they begin to appear in woods, in city parks, and in trees near buildings. Many species go on farther north for their nesting. Some warblers go as far north as the Hudson Bay and the Yukon Territory in Canada, but others nest in the Southern States. Blackburnian Warbler Dendroica Fusca Found from Canada to Northern South America.
Warblers build their nests in trees and bushes or on the ground.
The nests are usually cup-shaped, and loosely built of twigs and grasses woven together, but some are compact structures of plant down. The female warbler lays from three to six eggs, which are whitish with brownish markings at the larger end. Many kinds of warblers have fine singing voices. Others sing only weak, lisping notes. There are more than 150 species and subspecies of warblers.