Black-throated Green Warbler

 

 

Common Name:Black-throated Green Warbler

Class:Aves

OrderPasseriformes

Family:Parulidae

Genus: Setophaga

Species:Setophaga virens

Photo: Sara Morris

 

TAXONOMY

The Black-throated Blue Warbler is a small bird in the order Passeriformes, the order that includes the songbirds, and is a part of the family parulidae. This species, like many of the other songbirds, is sexually dichromatic. This means that the males and the females do not look the same in the outward appearances, their plumage coloration varies greatly between the sexes. In general, these birds weigh approximately 8.8g and are about 5 inches in body length. The males and the females are difficult to tell apart from first glance. They are both bright green above on the top of the head and running down the back of the neck. Both sexes have a yellow face with olive cheeks and streaked black and white wings with streaks down their sides. To tell the males from the females is easier when viewing from the front. Adult males have thicker black streaks down their sides as well as the expected black throat.

Photo: Sara Morris

HABITAT/DIET

Black-throated Green Warblers can be found in their breeding grounds in the Northeastern United States and Southern parts of Canada to Eastern British Columbia. Breeding grounds may also include Alberta, Quebec Newfoundland, along the Atlantic seaboard to New Jersey as well as the Appalachian mountains. They travel south to their wintering ranges, which include places such as Mexico and Central America to central Panama.

This species prefers to live in relatively undisturbed woodlands, boreal coniferous forests or mixed deciduous and coniferous forests and have been found in all deciduous forests. Often found in areas containing white pines and hemlocks. They live in forested areas where the food that they need is relatively abundant. During the breeding season a majority of the diet consists of insects, especially caterpillars. They will consume berries if need be, but they prefer insect species and they are very efficient foragers who can hover to catch prey or pick insects off of the underside or top of a leaf. This species has been seen drinking from water collected on needles.

 

BEHAVIOR

 

Black-throated Green Warblers can usually be found hopping along the forest vegetation as well as on the ground. When they fly they make short, rapid movements and fly directly between trees, less often do they fly above the trees. They tend to spend a majority of the day foraging with the remainder of the time spent singing, resting, or preening.

 

This species is territorial and during the breeding season the males will search out territories, in early spring several days before the females arrive, and often there are male agonistic interactions for the acquisition of good territory. The males have elaborate displays of chasing one another and fleeing, there is much energy expended to do this while in flight. Males will also sing, mostly at dawn and dusk, to help them maintain their territories as well as to attract a female. The breeding territories are where the male and female will spend mostly all of their time and territory size can vary depending on the habitat. Once males have attracted a female, by performing courtship displays such as fluffing out his feathers, the male will try to guard his mate especially during the nest building stage and the time directly before egg laying. Other than interacting with their mates, Black-throated Green Warblers will usually keep a fair distance one another, especially during the breeding season.

 

Females are the main nest builders of the species and are often seen, in the spring, foraging for nesting materials, such as small twigs, mosses, feathers, and grasses. Females will make a cup shaped nest out of pieces of vegetation and these nest are usually situated in low, 1-3m above ground, vegetation in a fork to support the nest and often near the trunk of a tree, often coniferous, for added stability. Once the nest is complete females will begin to lay one egg a day ending with an average clutch size of 3-4 eggs, speckled and cream with tones of grey in color. Females then incubate their eggs for approximately 12 days until altricial chicks hatch and then parents care for them until they fledge approximately 11 days after hatching.

 

WHERE TO FIND THEM

 

The Black-throated Green Warbler can be found along the trails at the Tifft Nature Preserve located outside of Downtown Buffalo. They have recently also been sighted at Sprague Brook State Park, Amherst State Park (formerly Glen Park), and Forest Lawn Cemetery.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

                Photo: Sara Morris

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.