Introduction

The White-eyed Vireo is a migratory songbird more frequently detected by ear than by eye. Although this species is cryptic in both plumage and behavior, male White-eyed Vireos compensate with explosive and complex singing. Individuals have repertoires of a dozen or more distinct songs, each comprising six to ten highly variable elements. Because of its complex song delivery, this species is a compelling subject for studies of vocal communication.

The White-eyed Vireo is common in its preferred habitat of dense secondary deciduous scrub, wood margins, and overgrown pastures. On its wintering grounds it is sympatric with several closely related vireos but avoids interspecific competition by use of habitat shift, niche partitioning, and interspecific territoriality. In the breeding season, White-eyed Vireo males defend territories for the monogamous breeding pair. Nests are pendulous cups and usually well hidden in dense growth. Both parents participate in nest-building and care for young. Nearly half of all White-eyed Vireo nests are parasitized by Brown-headed Cowbirds (Molothrus ater), in which case vireo offspring do not survive.

A principal restriction on the White-eyed Vireo appears to be the availability of suitable habitat. Since the dense scrub this species prefers has little economic value, it is rarely protected. The White-eyed Vireo is more variable in habitat use on its wintering grounds, however, and probably has not been seriously harmed by habitat changes in the subtropics. Although its numbers have shown a slight decline, the species has expanded the northern edge of its range. As long as secondary deciduous scrub is available, the White-eyed Vireo most likely will continue to thrive.