Conservation of Raptors
photograph of a Peregrine Falcon by Rohan Kamath
some areas populations and species of raptors are threatened
with extinction -- more so than many other kinds of birds.
There are five reasons. First, raptors are often directly
persecuted by people who believe (usually erroneously) that
these birds are a threat to livestock. The antiquated notion
that birds of prey are "varmints" remains entrenched, and
many otherwise law-abiding farmers and ranchers kill hawks
and eagles, while some "hunters" take potshots at them. This
is illegal, since raptors are federally protected against
Second, a great many hawks, falcons, and owls are taken for an illegal taxidermy trade, mainly in Europe. Reportedly thousands of Northern Goshawks are slaughtered and stuffed each year in China alone.
Third, falcons are illegally
trapped by smugglers lured by the enormous price that the
birds will bring in the Middle East, where falconry is a
high-prestige activity for the elite. The majority of
falcons used by the Arabs are migrant Sakers (Falco cherrug)
from Asia. Sakers are a species that is rather like a
slightly smaller version of the Gyrfalcon. Gyrfalcons
themselves, because of their long wings and large size, are
especially prized. Members of the Middle Eastern royal
families have reportedly paid up to $100,000 each for
healthy specimens of these arctic raptors, of which perhaps
only 4,000-5,000 live in North America. It is not clear,
however, whether hunting, trapping, or nest-robbing of
falcons has ever led to widespread permanent reductions in
falcon populations. Cornell ornithologist Tom J. Cade
suspects that birds killed by hunters or taken by falconers
are largely part of the "expendable" surplus produced by
Fourth, raptors are generally rather long-lived birds and feed high on food chains, which makes them more susceptible than short-lived or plant-eating species to poisoning by pesticides and other pollutants. Poisons accumulate in organisms over time, and poisons become concentrated as they move up food chains. There is no question that toxic substances have had catastrophic impacts on the populations of some raptors. Peregrine Falcons, for instance, were eliminated from much of North America through the large-scale use of DDT and its relatives, which began shortly after World War II. By 1964 Peregrines had been exterminated east of the Mississippi. They subsequently continued to decline sharply in the West and North.
Laws have been promulgated to limit the use of persistent pesticides that threaten raptors. The application of DDT has been largely banned in the United States since 1972, although it is a contaminant in dicofol (the main ingredient of Kelthane), a related chlorinated hydrocarbon pesticide, which is legally used. (There may also be illegal use of DDT itself.)
Finally, raptors, especially large ones, often suffer from habitat destruction, which makes areas with sufficient space for home ranges or suitable nesting sites scarce. This is the overriding problem for tropical forest eagles.
Laws now attempt to protect raptors from the depredations of hunters. Some individuals have been prosecuted under the Endangered Species Act for killing Bald Eagles. Fines as high as $5,000 and jail terms of up to six months have been dealt out to those convicted of this crime, which is being taken more seriously as time passes. And in 1984, the U.S. Fish and Wildlife Service arrested 39 people suspected of being involved in illegal commerce in falcons.
In addition to legal protection, steps can be taken to help preserve raptor populations in deteriorating habitats. For example, provision of artificial nesting sites has led to an increase in Osprey populations and shows potential for doing the same for Bald Eagles. In one ingenious program, Osprey nest poles were dropped like darts from helicopters into coastal salt marshes. Another helpful step toward protecting many large raptors, as we are often reminded through magazine and television advertisements, has been providing insulated perches on the tops of power poles carrying high voltage power lines.
Populations of the Peregrine Falcon have been reestablished in areas from which it had been exterminated. Tom Cade pioneered a program of captive breeding and releasing primarily in the eastern United States, where DDT-induced breeding failures had led to the falcon's extirpation. After the use of DDT was banned in 1972, the birds could once again survive there; with skill and persistence Cade's team started the species on the road to recovery in the wild. Recovery to the pre-DDT level of some 400 breeding pairs in the eastern United States may be rapid. In 1978 no pairs nested in the East; in 1984, 27 pairs did. In 1985 there were 38 breeding pairs, and young were fledged by at least 16 pairs. In addition, during the summer of 1985, 125 young Peregrines reared in captivity were released in the eastern United States and 135 in the West. In 1986 there were 43 territorial pairs, and 25 of them fledged 53 young. Due to efforts by the Peregrine Fund of Boise, Idaho, these numbers continue to improve. As of 1995, there were 98 breeding pair in the East, 68 in the Midwest and 829 in the West.
Legal protection against shooting, capturing and poisoning, habitat improvement, and reestablishment programs all help preserve birds of prey, but in the long run these measures alone will not be enough. Without public education about raptors' esthetic and direct economic value, laws are likely to contain too many loopholes and will likely be enforced with insufficient vigor. And as with the entire extinction problem, long-term solutions almost certainly will depend on changing attitudes toward our fellow creatures, and reduction of the appropriation of Earth's resources by Homo sapiens. Until then, habitat destruction will continue to accelerate the loss of species -- both spectacular ones that attract our interest and more obscure ones on which our favorites (and we) often depend.
Birds and the Law;
DDT and Birds;
Conservation of the California Condor.
Copyright ® 1988 by Paul R. Ehrlich, David S. Dobkin, and Darryl Wheye.