Blue-headed Vireo

The Blue-headed Vireo, Vireo solitarius, is a small Neotropical migrant songbird adorned with an olive green upper body and striking yellow wing bars. Its namesake blue-grey crown is a distinctive feature, along with its white underparts peppered with subtle grey streaks. Both sexes exhibit similar plumage and size, making them indistinguishable in the field. Juveniles mirror the adults in their feathering, ensuring a consistent appearance throughout the year.

Identification Tips

To identify the Blue-headed Vireo, look for the following characteristics:

• Length: 126–148 mm (5.0–5.8 in)
• Wingspan: 200–240 mm (7.9–9.4 in)
• Weight: 13–19 g (0.46–0.67 oz)
• Olive green upperparts
• Blue-grey crown and nape
• White underparts with light grey streaking
• Two bold yellow wing bars
• White throat and supercilium
• Dark eye-line

Habitat

The Blue-headed Vireo thrives in large temperate forests, favoring a mix of evergreen trees and deciduous undergrowth. During the breeding season, they are found in cool, higher elevation forests, while in winter, they reside in mixed woods, coastal swamps, and shrubby thickets.

Distribution

This vireo's breeding range spans across Canada and the eastern United States, with two recognized subspecies differing slightly in size and distribution. The V.s. solitarius subspecies breeds from northeastern British Columbia to southern Pennsylvania and New Jersey, while V.s. alticola is found in the Appalachian Mountains to northern Georgia. In winter, they migrate to eastern and southern Mexico and parts of Central America.

Behaviour

During migration, Blue-headed Vireos may flock with various sparrow species but seldom with their own kind. They exhibit a low population density year-round, which is influenced by the forest type they inhabit.

Song & Calls

The male's primary song is a simple, slow, and monotonous melody, reaching peak frequency before mating. Both sexes communicate with high-pitched chirps while foraging, especially during the breeding season.

Breeding

Males establish large territories to attract females, with the size of the territory being a key factor in mate selection. After pairing, the couple builds a nest in mid-level tree branches, where the female lays 3–5 eggs. The male participates in incubation and chick rearing, displaying an unusually high level of paternal care for the species.

Similar Species

The Cassin's Vireo (Vireo cassinii) is similar in appearance but can be distinguished by its lighter yellow patches, smaller bill, and brownish-grey crown.

Diet and Feeding

Primarily insectivorous, the Blue-headed Vireo also consumes berries and fruit. They forage in mid-level tree branches, hopping and flying to capture prey like caterpillars, moths, beetles, and various other insects.

Conservation status

Since the 1970s, the population of the Blue-headed Vireo has been on the rise. As of 2004, it is classified as "Least Concern" by the IUCN, indicating a stable population status.