Laura Erickson's For the Birds

Tuesday, February 14, 2012

White-eyed Vireo

(Transcript of Wednesday's For the Birds)
White-eyed Vireo

A sputtery little bird of the Southeast, the White-eyed Vireo, produces a dozen or more distinctive songs, each with six to ten highly variable elements, learned by imitating his father and neighbors. But because the notes are delivered so quickly and the songs share the same sputtering quality, many birders who easily identify vireos don’t appreciate the complexity of their songs.

White-eyed Vireo

White-eyed Vireo songs may be wondrously complex for aficionados, but these tiny, secretive songbirds are so active, and so good at keeping hidden within dense foliage, that many people tune out their incessant singing. That’s a real shame, because even a quick peek at a White-eyed Vireo can be exciting. The soft grays and yellows of their cryptic plumage are pleasing, and the white iris of their eyes is arresting. When the sky or nearby foliage is intensely colored, the iris may take on a soft milky bluish or greenish hue, but even with a slight reflection of color the white eye is strikingly beautiful.

White-eyed Vireo

How do you get a glimpse of such a secretive bird? During the breeding season, they sometimes scold nearby people, making themselves quite easy to see, but most of the year they don’t seem to pay much attention to us, unless we’re disrupting their normal behaviors by playing recordings. They may not actively avoid us, but as they flit about, they are more likely to be working their way away from rather than toward us. But once we start searching the leaves for their tiny flitting movements and learn to follow their song, our patience may be rewarded with a clear, albeit brief, look.

Russ and I spent one morning this January at Lake Kissimmee State Park in Florida. Our target was the Florida Scrub-Jay, one of my most beloved species, but right after a family of scrub jays appeared, a White-eyed Vireo started singing nearby, managing to divert my attention from the jays to himself. It took a full minute, which can feel like an eternity when you’re searching for a hidden bird while one of your favorites is right there in the open, but I finally found the little squirt. He stayed in view on and off for 22 seconds—not long, indeed, but I was watching through my camera and ended up with 18 photos, several of which turned out quite nicely.

White-eyed Vireo

If White-eyed Vireos are tricky for us to locate, cowbirds find tracking them far easier. Indeed, about 50 percent of all White-eyed Vireo nests are parasitized by cowbirds, and in these cases usually every one of the vireo chicks dies, if it managed to hatch in the first place. Cowbird eggs hatch 10-12 days after being laid. Meanwhile, it takes White-eyed Vireo eggs 13-15 days of incubation to hatch, and that time can be lengthened if the larger egg of a cowbird is present, holding the incubating adult vireo’s body further from her own eggs.

During winter, White-eyed Vireos usually keep their distance from other small birds of their own and other species by partitioning their habitat and sometimes driving other birds away, but sometimes they join mixed flocks with other species, especially during migration while they’re passing through unfamiliar areas. Most populations have a lull in singing in fall and winter, but the resident Florida subspecies does n’t, which is how I was able to so easily enjoy the one I had so much fun with in January. The spring singing period for a White-eyed Vireo wintering along the Gulf Coast begins as early as February. Being alert to their brief but oft-repeated song may provide you, too, with a quality experience with this tiny sprite.
White-eyed Vireo

Production of today’s For the Birds was made possible in part by a generous grant from Vickie and Barry Wyatt.