Measurements
Both Sexes
- Length
- 4.3–5.1 in
11–13 cm - Wingspan
- 6.7–7.9 in
17–20 cm - Weight
- 0.3–0.4 oz
8–12 g
Other Names
- Paruline bleue à gorge noire (French)
- Reinita azul negra (Spanish)
Cool Facts
- The sexes of the Black-throated Blue Warbler look so different that they were originally described as two different species.
- On the wintering grounds the sexes use slightly different habitats. The male is most common in forest at lower to mid-elevations, while the female uses shrubbier habitat at higher elevations.
Habitat
Forest
- Breeds in mature deciduous and mixed coniferous-deciduous woodlands with a thick understory, often in hilly or mountainous terrain.
- Winters in dense tropical forests.
- On migration, found in variety of habitats, including forest, forest edges, parks, and gardens.
Food
Insects
Insects and some small fruits.
Nesting
Nesting Facts
- Clutch Size
- 2–5 eggs
- Egg Description
- Creamy white with dark speckles concentrated at the large end.
- Condition at Hatching
- Helpless with tufts of down.
Nest Description
Nest an open cup of strips of bark, held together with spider web and saliva. Places in fork of low shrub.
Nest Placement
Shrub
Behavior
Foliage Gleaner
Forages mostly in lower to mid-levels of forest, taking insects mostly from the underside of leaves.
Conservation
Least Concern
Probably decreased markedly with destruction of eastern forests in 17th and 18th centuries. With the beginning of abandonment of farms in New England in the late 19th and 20th centuries, populations rebounded. Currently populations seem stable.
Credits
- Holmes, R. T. 1994. Black-throated Blue Warbler (Dendroica caerulescens). In The Birds of North America, No. 87 (A. Poole, and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, PA, and The American Ornithologists' Union, Washington, D.C.