Word: ddt
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Dates: during 1970-1979
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Native-born peregrine falcons-not plentiful even when they were thriving -had not been seen in the skies over the Eastern U.S. for some 20 years. But now this fierce, graceful bird of prey, driven to the brink of extinction by DDT,* appears to be making a comeback. Ornithologist Tom Cade and his colleagues at Cornell University have succeeded in breeding peregrines in captivity and releasing them in the wild, where they can once again be seen soaring to great heights before diving on their prey at speeds of up to 200 m.p.h...
...York, New Jersey and Maryland. This summer he hopes to set 34 free in the Eastern U.S. His goal: to release enough young birds so that the peregrine can re-establish itself in the East and breed naturally, now that there is a near-total U.S. ban on DDT...
...pesticides proved to be a mixed blessing. Beginning in the late '40s, researchers began to discover traces of DDT ?which degrades, or breaks down, very slowly?in the tissue of fish, wildlife and humans. At about the same time, scientists began to report that the chemical was causing some species of birds to lay eggs with abnormally thin shells that broke during brooding; as a result, the numbers of ospreys, peregrine falcons, bald eagles and brown pelicans were declining. These revelations were followed by the publication in 1962 of Rachel Carson's book, Silent Spring, which began to crystallize...
...DDT's demise was followed by those of other insecticides. In October 1974, the EPA halted the manufacture and restricted the sale and use of two products that are highly effective against corn pests: aldrin and dieldrin, which had also been linked to cancer in laboratory animals. Last year, for the same reason, it placed severe restrictions on the sale and use of heptachlor and chlordane, effective termite killers. The EPA has also curtailed the use of Mirex, the pesticide that is most effective against the fire ant as well as harvester and Texas leaf-cutting varieties. Tests showed that...
...away the insecticides that really do the job," says Steve Pfister, a Lexington, Neb., corn and alfalfa farmer. But entomologists and some farm experts feel that in the long run, less dependence on pesticides will be beneficial to the farmer. Many scientists believe that the introduction of pesticides like DDT, which promised easy pest control, actually intensified the problem by encouraging the abandonment of such traditional?and sound?agricultural practices as rotating and diversifying crops and adjusting times of planting to avoid insect infestations. "Insecticides have failed not because of any inherent weakness in the concept of reducing insect populations...