Geography/Habitat:

The Blue-headed Vireo, (Vireo solitarius), was formerly classified as a single species – Solitary Vireo with the Cassin’s and Plumbeous Vireo. The Solitary Vireo was split in 1997. First described by Alexander Wilson in 1810 in Philadelphia, the split is based on recent genetic studies though some hybridization occurs where there is some range overlap. Note that 2 sub species are recognized.

The Blue-headed Vireo breeds across central and Eastern Canada down into the Northeastern US. It Winters along the eastern US Seaboard down to Florida and West through to Texas and down through Eastern Mexico and into Central America as far South as Nicaragua.

Blue-headed Vireos prefer open mixed woodlands in both breeding and non-breeding seasons and nest in the medium story building a cup nest of twigs grass and bark and lined with grass and hair. Breeding season is late April to July and 3 to 5 white speckled eggs are laid. Note the male chooses several possible nest sites, leaving a gift of food at each one, and the female chooses the final site. The eggs are incubated by both parents for around 15 days. The young fledge after 10 to 12 days but are cared for by the parents for a further 2 to 4 weeks.

Food supply is primarily insectivorous including bugs, beetles and caterpillars but in winter, seeds and berries are also eaten. It gleans from trees in a very deliberate manner but will occasionally “fly catch” in mid-air.

Identification

The Blue-headed Vireo is medium-sized but appears large-headed. The upperparts are olive green with whitish underparts and yellowish flanks. The wings are darker with two distinct white wing bars. The head is blue gray with white spectacles extending to the heavy black bill. Note the spectacles are fringed with black. Note the Plumbeous and Cassin’s Vireos are very similar. Cassin’s Vireos are more greenish and show less contrast between cheeks and throat. Plumbeous Vireos show no yellow at all but are again very similar.

The Blue-headed Vireo song is slow drawn out set of phrases “cheery o wit” with call notes being a scolded rattle.

Fun Facts

• Due to an early breeding season nests are usually constructed in evergreen Hemlock trees. Note an invasive bug from Asia is decimating the Hemlock and is causing major issues for the vireos to find a suitable place to nest.
• A lack of Hemlock means that breeding season is arriving later until deciduous trees are suitable for nesting.
• A group of Vireos is known as a Call.