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Meet the AnimalsPeregrine falcon These remarkable birds make a strong comeback.
But beginning in the late '40s, peregrine populations suffered a quick and steep decline, and by the 1960s there were virtually no peregrines alive along the east coast of North America. Other raptors (predatory birds) also had a sharp decline in numbers at that time, and eventually scientists discovered that the pesticide DDT, which was in widespread agricultural use at the time, was concentrating in the bird's bodies, and especially in the minerals that became eggshells. The DDT made the eggshells so weak that any disturbance cracked them open. Although the pesticide didn't kill the grown birds, no new peregrine falcons were being born. In 1972, DDT use was banned in the United States, though the pesticide is still legal in some other countries. Since then the chemical has slowly disappeared from our environment. Peregrine falcons, and other raptors, have made a remarkable recovery. That recovery didn't happen by chance. The U.S. Fish and Wildlife Service, along with state wildlife agencies and private foundations such as The Peregrine Fund, released over 6000 captive-bred peregrine chicks into the wild. Some populations, such as the peregrine falcons found in the Arctic, were strong enough that they began to recover on their own. But in many places the reintroduced birds were the only way that populations of peregrine falcons could recover. Today scientists estimate that there are at least 6,000 breeding pairs of peregrines in the United States and Canada. In 1995 the peregrine falcon was taken off the endangered species list, as the government declared the bird was no longer in danger of extinction. The survival of these beautiful birds is a tribute to the commitment and dedication of all those who worked for so many years to keep them alive. These people carried the tiny chicks to tall mountains, released them there, and then watched over them until they grew large and strong enough to survive on their own. Of course, it's not always easy to know when a species is finally out of danger. Some scientists still believe that this bird is in danger. They point to the fact of continuing DDT use in some countries, and other pesticides such as DDE which continue to concentrate in the bodies of predator birds. In addition, the cliffs and mountains which are the birds' natural home have changed in many places, as forests have overgrown such historic falcon habitat as the Appalachian mountains. Other defenders of the peregrine believe that the species is truly recovered, and will continue to survive and even thrive. They counter that there are many other species in far more danger than the peregrines, and that our limited resources should now be spent helping other birds get reestablished. If you are lucky enough to see one of these lovely birds, with their sharp wings and dark brown hood, flashing over a mountain cliff or along the edge of a modern skyscraper, take a moment to appreciate not only its beauty, but the years of effort that went into ensuring that the peregrine falcon would survive. Related links: Peregrine Falcons: Fastest Birds in the Air Pennsylvania's Peregrine Falcon Page U.S. Fish and Wildlife Service: Peregrine Falcons Photo © Corel Corp. Return to Meet the Animals |
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Peregrine falcons were never really common in North America. Like all predators, these sleek birds occupy a particular niche in the food web — at the top. Unlike prey animals such as mice or deer, which reproduce in large numbers in order to keep their species alive, predators such as falcons exist in smaller numbers and reproduce slowly, usually staying in some balance with the amount of food available to them. In the 1930s and 1940s, studies estimated there were about 1500 breeding pairs of peregrines in the United States and Mexico.
