Warbler, the popular name of two unrelated families of birds. The true warblers are chiefly Old World birds. The wood warblers live in the Americas. Both families are valued because they feed almost entirely on insects and insect eggs.

What Is a Warbler?

A warble (WOHR bul) is a special kind of song that has many trills. Trills are vibrating, high-pitched sounds. Many songbirds sing this way. In fact, two families of birds sing this way so often that they are known as warblers.

Wood warblers live in North America and South America. These birds are only about 51/2 inches (14 centimeters) long.

Yellow warblers are very common wood warblers. The male is bright yellow with orange streaks on his breast. The female is a dull yellow color. The male’s song sounds like “Sweet, sweet, sweet. I’m so sweet!”

The other family of warblers lives mainly in Europe, Asia, Africa, and Australia. These birds are known as Old World warblers. Like wood warblers, they sing high-pitched songs.

The tailorbirdThe tailorbird is a warbler that uses its long bill as a needle.
True Warblers

There are more than 330 species of true warblers, only 3 of which are found in North America. True warblers are small, drab birds about four to six inches (10 to 15 cm) long. Many species are noted for their intricate songs.

The golden-crowned kinglet is olive-gray above and white below. The male has an orange crown patch, the female a yellow one. The bird breeds as far north as southern Canada and winters from southern Canada to Guatemala. The ruby-crowned kinglet is olive-gray with white and black bars on the wings. The male has a scarlet crown patch. The bird breeds as far north as southern Canada and winters from southern New England to Guatemala. Both species flick their tails when perching.

The blue-gray gnatcatcher is blue-gray above and white below. It has a white ring around the eye and a black-and-white tail. It breeds as far north as southern Canada and winters chiefly in the southern United States.

Kinglets and gnatcatchers build cup-shaped nests of mosses, lichens, and other plants, suspended from tree branches. The nests are lined with feathers.

True warblers make up the family Sylviidae. The golden-crowned kinglet is Regulus satrapa; the ruby-crowned, R. calendula; the blue-gray gnatcatcher, Polioptila cerulea.

Wood Warblers

Wood warblers are usually about five inches (13 cm) long. There are about 115 species, 40 of which are found in North America. Birds of most species are difficult to see because they are active, constantly flitting about in bushes and high trees. Wood warblers are yellow and olive-green with patches of black, white, and red. The following species have typical coloration patterns.

The black-and-white warbler has black-and-white striped plumage. The prothonotary warbler is golden yellow with an olive back and blue-gray wings. The worm-eating warbler is olive with black stripes, and a buff-colored head and breast. It feeds on the wormlike larvae of moths. The male cerulean warbler is light blue with a black band across the chest; the female is olive above and buff below. The yellow warbler is bright yellow with an olive-green back and yellow spots on the tail. These five species breed in the eastern United States and winter in Mexico and South America. Townsend's warbler is olive-green with a yellow-and-black striped breast and a black eye patch surrounded by a yellow ring. It breeds in the Pacific Northwest and winters in Central America.

Wood warblers make up the family Parulidae. The black-and-white warbler is Mniotilta varia; the prothonotary, Protonotaria citrea; the worm-eating, Helmitheros vermivorus; the cerulean, Dendroica cerulea; the yellow, D. petechia; Townsend's, D. townsendi.