BLACK VULTURES
| There are two kinds of
buzzards in the southern winter sky, Turkey Vultures and Black Vultures.
When High Plains Turkey Vultures seem to disappear, they’ve gone south
to join Black Vultures for the winter. Both range maps have an uncanny likeness to a map of the Civil War. Turkey Vultures live on one side or the other, Union states in warm weather, Confederate states in cold. Black Vultures tend to stay year-round within the borders of the former Confederacy, sharing it with their cousins when they come south. Today the ranges of both buzzards are expanding, and Black Vultures are increasingly seen in the High Plains sky. So it seems advisable to learn a bit more about them. Both are about the same size, but Turkey Vulture wings are longer, while Black Vulture bodies are heavier. What’s most obvious in the air is the Black Vulture’s short, nearly nonexistent tail, and its almost flat, black wings. The V of a Black Vulture in flight ranges from shallow to nearly horizontal, and there’s less of the rocking motion seen in Turkey Vulture flight. High in the sky, the small head and tail seem to disappear, and for this they call the Black Vulture “The Flying Wing.” The Black Vultures I’ve seen did seem less like birds than a set of two wings joined in the middle, unencumbered by rudder or brain. Occupying a somewhat higher altitude, Black Vultures often follow Turkey Vultures soaring just below them. Turkey Vultures, with a better sense of smell, are often first to discover food — when they do, Black Vultures swoop down and join in. In temperament, Black Vultures are more aggressive than their mild-mannered counterparts — when sharing a carcass, Black Vultures eat first. Black Vultures are entirely black except for some white on their wingtips. In some lights those black wings have fingertips of silver. In other lights, the primary shafts seem white as well, in the same way a Red-shafted Flicker shaft is red. A Black Vulture’s white wingtips are visible from above and below. The naked wrinkled heads and necks of Black Vultures are blackish, and the legs and feet are smudgy gray. Nakedness allows the birds to probe deeply into carrion without becoming covered in gore. Just as the eagles picked at Prometheus’s liver, so do vultures seek to eat the inner organs of their prey (which at least unlike Prometheus is already dead). The absence of feathers is also believed to aid in heat regulation. Vultures frequently perch with their wings spread wide, either facing the sun or directly away. This serves to cool down or warm up the bird by airing the feathers or increasing available surface area for absorbing heat. Both vultures have another way of cooling themselves that I almost hate to bring up, but the truth, as I’m sure you know, is sometimes gross. Buzzards cool their legs and feet, you see, by urinating on themselves and then letting it evaporate. This “urohidrosis” accounts for the fact that buzzard feet often appear to be white. It often seems that when it comes to Vultures, both Turkey and Black, repulsion is the greater part of our reaction. We naturally recoil from their choice of food, their appearance, and doubtless their smell, and by certain of their habits as well. But however they seem to us, vultures render mankind an invaluable service — without Black and Turkey Vultures, the world would be a far messier place. [I studied Black Vultures at Birds of North America Online, and in David Allen Sibley’s Sibley Guide to Bird Life and Behavior.]
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