Black vultures, shown basking in
the sun to warm up on a recent chilly morning,
are smaller than turkey vultures, which can weigh up
to 6 pounds. Photo by Jerry Lower
By Joanne Davis
They start migrating in October, and by early to mid-November they are here.
They come from everywhere east of the Mississippi River and from as far away as Canada.
Their endless, effortless soaring sends large shadows gliding across the ground, across us, and makes us squint to glance skyward. They are dark, ominous against the blue, but their grace and mastery of the thermals brings us pause and a wonder to understand them; to get past their soiled reputation.
They are the carrion eaters, the vultures, mysterious beings of the sky.
In South Florida we have two vulture species. Turkey vultures, which are both resident and migratory, and black vultures, which are smaller and mostly resident. Both have large populations here in winter.
An adult turkey vulture weighs approximately 6 pounds, with a wingspan of about 6 feet. They have a bare, red head. Black vultures are about 4 to 5 pounds with a wingspan of about 4½ to 5 feet. The head is dark gray to black and bare.
Brian Smith, coordinator of the American Bird Conservancy in the Appalachian Mountains, says, “Vultures get a pretty bad rap because of what they do.”
What they do is eat carrion. When they are frightened they regurgitate. This is sufficient to repel any would-be predators, just from the smell alone.
And if that isn’t repelling enough, the turkey vulture often directs its urine right onto its legs. This serves two very important purposes: In the summertime, wetting the legs cools the vulture, as the urine evaporates (the vulture cannot sweat like us). And the urine contains strong acids from the vulture’s digestive system that kills any bacteria that may remain on the bird’s legs from stepping in its meal.
When the vulture is eating carrion, it must often stick its head inside the carcass to reach the meat — which explains the vulture’s bald head. A feathery head would capture unwanted pieces of the vulture’s meal, along with all the bacteria it hosts. After mealtime, the turkey vulture perches in the heat of the sun to bake off whatever leftover has managed to cling to the few bits of fuzz on their head.
Neither vulture species builds nests. They lay eggs in a small depression on the ground, among rocks in caves or old buildings.
Vulture populations are increasing near human habitation. They like our landfills, our roadkill, and they like roosting on our cell towers. They have benefited from our waste and our activities.
“People look down on vultures as not very elegant in the bird world, but they play an important role in nature,” said Craig Watson, wildlife biologist with the U.S. Fish and Wildlife Service.
Vultures have a tough job — not one many of us would care to do. And they do it for free — a perk in the service that nature provides that we rarely consider.
So, next time that shadow runs across the ground, look up at the grizzly looking bird that is looking for a mess to clean up, and give a thank you — from a distance.
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