When the Endangered Species Act was passed in 1973, peregrine falcons were one of the first species to receive protection. By the time DDT was finally banned in 1972, there was not a single peregrine falcon left east of the Mississippi. The eggs shattered before fledglings could hatch. Through a process known as biomagnification, DDT accumulated in the peregrines, causing their eggs to become too weak to even support the weight of the mother incubating her eggs. The sparrows, pigeons, and other small birds that peregrines hunted fed on insects contaminated with DDT. Capable of flying at speeds of up to 60 miles per hour in level flight, the peregrine is one of the world’s fastest birds.īut in the 1950s and ‘60s, the chemical dichlorodiphenyltrichloroethane (DDT), used widely in agricultural pesticides, found its way up the food chain. One of nature’s most skilled hunters, the peregrine falcon dive-bombs its prey at speeds of up to 200 miles per hour. Until the middle of the 20th century, the crow-sized, dark-capped, blue-gray peregrines ruled the skies and rocky mountaintops from Alaska all the way to Georgia, preying on smaller birds such as sparrows and pigeons. The reemergence of the peregrine falcon ( Falco peregrinus) in North America is one of the environmental movement’s greatest success stories. Pairs of peregrine falcons have been found nesting on the window ledges of such buildings as the Metropolitan Life Building, adjacent to this parkland.
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