Voice: Males: song can be rendered as “here I am, where are you, over here.” It is a bit slower than a Red-eyed Vireo.
Blue–headed vireos are the only vireo that makes use of mixed forests, where conifers and deciduous trees grow together. They prefer forests composed of large mature trees with closed canopy and rich but not dense shrub layer. They are common breeders across boreal Canada, New England and along the spine of the Appalachian Mountains. In Ohio, they are rare breeders confined to extensive hemlock ravines.
In the summer, Blue-headed vireos forage in canopies of mature forests. They search slow and methodical, tilting their head back and forth, searching for prey along sturdier tree branches. They rarely venture out onto the springy tree tips but will fly out to catch a prey in mid-air. Blue-headed vireos feed primarily on insects, including caterpillars, stinkbugs, beetles, weevils, wood borers, moths, butterflies, grasshoppers, bees, ants, and crickets. They will eat other invertebrates such as spiders and snails. During migration and in winter, Blue-headed vireos frequently join mixed-species flocks when foraging. One fourth of their diet is made up of small fruits including sumac, wild grape, dogwood, elder, and wax myrtle.
Males arrive in early spring to select nest sites primarily in conifer trees. They choose conifer trees partly due to early arrival of available foliage to conceal nests. When courtship begins, male blue-headed vireos sing, quiver their wings, and hop or fly toward females showing off their white spectacles. Pairs build nests together usually six to fifteen feet up in a fork of a branch, most often a sapling conifer including hemlock, fir or spruce. They may also build nests in deciduous saplings and shrubs, including birch, oak, maple, hickory, beech, rhododendron, and chokecherry. The hanging cup nest measures three inches across by six inches tall. The nest is held together with spiderweb and comprised of bark, lichens, various plant fibers, twigs, moss, leaves, fur, and feathers. Females line the nests with grasses, rootlets, vines, and pine needles.
Females lay three to five lightly brown and black spotted whitish eggs. Incubation by both parents is twelve to fourteen days. Both parents also feed the young after hatching. Young leave the nest about two weeks after hatching.
According to Partners in Flight, Blue-headed vireos estimated global breeding population is 13 million individuals. Their distribution may be sensitive to habitat changes, especially clearcutting, forest fragmentation and global climate change. In addition, Blue-headed vireos dependence upon Eastern Hemlocks could cause local population to decline with the growth of an invasive species, the hemlock wooly adelgid. Introduced from East Asia, this insect sucks sap from trees and kills the tree within 4-10 years. Blue-headed vireos may not be able to find adequate nesting sites to reproduce in Ohio without hemlock trees.
Photo Credit: Melissa McMasters, CC BY 2.0 , via Wikimedia Commons