Black-throated Blue Warbler

 

Common Name: Black-throated Blue Warbler

Class:  Aves

Order: Passeriformes

Family: Parulidae

Genus: Setophaga

Species: Setophaga caerulescens

Photo: Steven Pitts

 

TAXONOMY

Black-throated Blue Warblers are passerines in the Parulidae family which groups them together with other Wood Warblers. They are about 5.25 inches (13cm) in size. Males have white upperparts and blue upperparts. They also have a black face, throat and sides. They have a white patch at the base of their primaries.  Females overall are a light brown color with a gray crown and cheek patch and white supercilium. They have grayish and yellowish underparts. These male and female Warblers differ more than any other  Wood Warbler that early naturalists identified them as two different species.

Photo: M. Noonan

HABITAT/DIET

Black-throated Blue Warblers live in undisturbed mixed and deciduous forests with thick undergrowth and rhododendron bogs. They breed in northeastern United States and southern Canada. They are as far south as the Appalachian Mountains. Black-throated Blue Warblers winter in the Greater Antilles. They are among one of the most studied passerine species in North America. This is because it is one of the few migratory species that has been observed in both breeding and wintering sites. They can be found in Western New York in the summer. Black-throated Blue Warblers eat fruit and insects about the ground while hovering. They eat mostly insects during the breeding season and will eat more plant material during the winter season.

 

BEHAVIOR

 

Male Black-throated Blue Warblers are one of the more aggressive warbler species where it is fairly common to see birds from adjoining territories  fighting over the border between two territories. When one male flies across this border the other male will fly quickly toward the intruder and gives a rapid series of chirps. If the other bird does not leave he will chase him in circles for as far as 300 feet. Sometimes these bird may even physically fight one another hitting the other bird with their wings, pecking, and locking their feet together to force the other bird to the ground. Black-throated Blue Warblers are thought to be monogamous but it is not known how many broods they have per year. The female lays and incubates about 4 creamy colored eggs for 12-13 days. The young are altricial which means they are blind, helpless and immobile. Both parents tend to the young until the young are ready to fledge which is 12-13 days after hatching.

 

WHERE TO FIND THEM

 

The Black-throated Blue Warbler is found in Forest Lawn, Tifft Nature Preserve, Iroquois NWR, and Allegany State Park during the migratory season and during the summer. They are mainly found in areas that have a lot of underbrush cover and they are mainly found in higher elevation forests.

 

Birds of Western New York is brought to you by the Institute for the Study of Human-Animal Relations at Canisius College in Buffalo, NY.