A specialty of Texas scrub oak habitats, the Black-capped Vireo is a snazzy songbird with a gleaming black head and thick white “spectacles” around bright red eyes. They are unusual among vireos in having differing adult male, immature male, and adult female plumages. These birds tend to skulk in thick scrub and can be hard to see, even though breeding males sing their long, varied songs through the heat of the day. This species was listed as Endangered until 2018, and is still on the Partners in Flight Yellow Watch List.
Black-capped Vireos nest in very specific habitats in a small range. Try using eBird to narrow down publicly accessible locations to look for them. In spring, males sing incessantly, often even through the middle of the day. Patience is indispensable with Black-capped Vireos, which seem to move just as they are spotted and usually remain buried in thick oak scrub. “Pishing” and squeaking may bring a bird into the open. Black-capped Vireos do not use feeders but often come to water-drip features in the morning and afternoon.
The Black-capped Vireo was federally listed as Endangered in 1987. Thanks to intensive efforts to preserve habitat and reduce nest parasitism by cowbirds, populations of this vireo recovered sufficiently for it to be removed from the list in 2018.
The Black-capped Vireo is the only vireo that shows sexual dimorphism, where the male and female look different. It also is the only one in which the male takes two years to reach adult plumage.
When Black-capped Vireos sing, they draw from a repertoire of syllables about 10 times larger than those of other vireos.
In most Black-capped Vireo populations, males greatly outnumber females, but the reason is not known.
It’s rare in nature for similar species to occur in the same habitat and eat the same food, but some vireos manage it. Black-capped Vireos have sometimes been found nesting near White-eyed, Bell’s, Gray, Yellow-throated, and Red-eyed Vireos—even sharing the same nesting bush with Bell’s Vireos. White-eyed, Bell’s, and Black-capped Vireos also forage in similar habitats—low, scrubby areas.
The oldest known Black-capped Vireo was a male, at least 12 years old, when it was recaptured and rereleased during banding operations in Texas, the same state where it had been banded.