Warblers

About one-half of the Old World warblers are resident or short-distance migrants that breed in tropical and sub-tropical ecosystems of Africa. Africa is also the wintering ground for many of the other species of Old World warblers, which migrate to more northern latitudes to breed. Various species in this family are widespread throughout Eurasia, breeding as far as the northern tundra, but wintering in the tropics of Africa or Asia. Other migratory species breed in more temperate habitats.

Only a few species of Silviid warblers breed in North America. The ruby-crowned kinglet (Regulus calendula) and golden-crowned kinglet (R. satrapa) are widespread and common birds of northern conifer forests. The blue-gray gnatcatcher (Polioptila caerula) is more southern in distribution, and prefers broad-leaf forests. The black-tailed gnatcatcher (P. melanura) occurs in desert scrub. These are all small, very active, insect- and spider-hunting birds. The gnatcatcher was named after it habit of catching small insects while hovering, or through brief, aerial pursuits.

Like other songbirds, male warblers sing to proclaim their breeding territory, and to advertise their availability as a mate to females. Some of the Silviid warblers of Eurasia are very difficult to tell apart on the basis of plumage, but they have different habitat preferences and distinctive songs.