Zoo Tales: Birds of Prey Quickly Becoming Birds of Peril
BY TOM GILLESPIE
Special to The Pilot
They're called birds of prey, or raptors, and their grace and beauty is legendary. They generally include hawks, falcons, owls, kites, eagles, ospreys, condors and some vultures.
High on the food chain, they have few predators - except the one who could cause their most rapid decline - man.
Birds of prey range in size from the huge, 30-pound Andean condor to the tiny, one-ounce Bornean falconet. Their weight is surprisingly light, though, due to their hollow bones and much of their body mass being feathers. A golden eagle, which can stand as tall as 40 inches, weighs only about 13 pounds.
Primarily, they feed on the flesh of other animals, grasping and killing their prey with their talons. It is a myth that the larger raptors, such as eagles, can grasp and carry off small children and larger domestic animals. A golden eagle, for example, weighs about 12 to 15 pounds. It can lift and fly away with only about one-third its own weight.
There are raptors on every continent except Antarctica. The Latin word "raptor" means "to grasp or seize," which is exactly how these magnificent birds capture their food - with the help of long claws, called talons, on the end of each toe.
The strong taloned feet are one of three characteristics that make a bird a raptor. A hooked upper beak for tearing prey into pieces and excellent eyesight are the other two. Raptors' eyesight is unequaled in the animal world.
An eagle, for example, has eyesight about nine times better than a human's. The eyes of most owls are so large, relative to their body size, that there is no room in the skull cavity for eye muscles. To compensate for this lack of eye movement, the owl is able to rotate its head about 270 degrees. To accommodate this movement, the owl has 14 vertebrae in its neck, as opposed to seven in a human. If an owl's head were the size of a human's, its eyes would be the size of softballs.
All birds of prey have a third eyelid, called the nictitating membrane, that can be closed across the eye to help protect the eyes when the bird dives into brush or plants to catch their prey. Some of the raptors, especially eagles, also have a protective brow ridge above their eyes for additional protection.
Under federal and state law, it is illegal for anyone to injure a bird of prey or to even own parts, such as feathers and talons. Federal permits are needed to own or keep them.
Birds of prey have been shot and trapped by farmers and ranchers; they have been poisoned by pesticides, and they have had their habitats destroyed and taken away by growing human populations and economic development. Only recently have humans begun to realize the value of these birds as controllers of rodent populations and as indicators of the general health of the environment.
Fortunately, it's not too late to save these birds, but it is essential that we all develop a more concerned attitude and tolerance for all the wild creatures that share the earth with us.
Visitors can see three species of raptors daily at the North Carolina Zoo: a female peregrine falcon (at the Rocky Coast exhibit), a female bateleur eagle (at the African Pavilion exhibit) and a male barred owl (at the Streamside exhibit).
Tom Gillespie works for the public affairs office of the N.C. Zoo.
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