The Black-throated Blue Warbler is one of the few warblers that has no yellow features. The sexes of this bird differ so dramatically, as compared with other warbler species, that the male and female were originally described as distinct species. It feeds on insects and small fruits.
General: 4 to 5 inches in length.
Adult Male: Dark blue crown, nape, back and wing coverts. White underparts. Black face, throat, and sides. White wing patch. Thin, pointed, black bill. Outer tail feathers have a large white spot with black tips.
Immature Male: Similar to adult males, except has a greenish wash to upperparts, yellowish wash to underparts, white tips on black chin feathers, and wing patch may be inconspicuous.
Female: Grayish-olive upperparts, crown, and cheek patch. Yellowish-white underparts. White supercilium. Dark wings and tail. Indistinct pale spot on outer tail feathers. White wing patch. Thin, pointed, black bill.
Winters in dense tropical forests. Found in variety of habitats during migration, including forests, forest edges, parks, and gardens.
3-5 eggs. The eggs are incubated by the female and have a 12-13 day incubation period. Fledging occurs in 11-12 days. The nest, built by the female, is an open cup made from bark strips, dead leaves, spider webs and moss. The nest is usually built 1 to 3 feet off the ground in a sapling, shrub, or small tree.
- Fort Rosecrans National Cemetary, Point Loma
- Santee Lakes, Santee