Beak of the Week – Black-throated Green Warbler

The Black-throated Green Warbler is one of the many species of warblers that migrate through the Upper Texas Coast and can be seen during spring migration. They can be seen in the area from March through May during spring migration and reappear in smaller numbers from August through November during fall migration. They are easy to distinguish from other spring migrant warblers and will join mixed flocks of warblers feeding on insects in trees.  It is easy to see why they are closely related to Townsend’s, Hermit, and Golden-cheeked Warblers as they look similar, but all have certain characteristics that set them apart from each other as well as different ranges.

Male Black-throated Green Warblers, as their name suggests, have a bright yellow face, greenish ear patch and back, and a black throat. Females have the same yellow face and green ear patch and back but have a white throat. They also have heavy black streaks on their sides. Their song is often described as a buzzy zee zee zo zo zee or trees trees I love trees. Depending on where they are, Black-throated Green Warblers can be found in a variety of forested habitats. In the northwestern part of their range, they nest in conifer forests. In the southeast, they can be found in mixed hardwood forests in the southern Appalachians. In the Atlantic Coast, they are usually found in cypress swamps. In the winter, these warblers prefer tall forests.

During the breeding season, Black-throated Green Warblers almost exclusively eat insects, which they will glean from deciduous and coniferous trees. During migration, they will also eat berries and feed on buds from cecropia trees in their tropical wintering grounds. During breeding season, the female chooses the nest site, which is usually 3-10 feet off of the ground in a tree. The female also does most of the nest building, which takes 4 to 8 days to complete.

When on their breeding territory, males are aggressive and will attack and chase rivals. Pairs are monogamous but will only remain together during the season until shortly after the young leave the nest.

Like many warblers, Black-throated Green Warblers are long-distance migrants and winter in Middle America, northern South America, and the West Indies. They will then migrate north through the eastern United States to their breeding grounds across the Appalachians, the Northeastern United States, and Canada. During this time, when these birds are migrating across the Gulf of Mexico, they can be found in forested habitats and sanctuaries across the area such as Boy Scout Woods, Smith Oaks, Eubanks Woods, Gast Woods, Dos Vacas Muertas, and the Edith L. Moore Nature Sanctuary. Keep your eyes in the trees for these black throated, bright faced beauties!