Eagles and DDT: I hope that the Pacific Legal Foundation Fixes this
A. Perhaps one of the most important reasons is the banning of DDT in the early 1970s. DDT is believed to have contributed to reproductive failure of eagles by thinning their eggshells.
Here is something to think about the next time you hear this claim:
While the AP acknowledged the fact that bald eagle populations “were considered a nuisance and routinely shot by hunters, farmers and fishermen” – spurring a 1940 federal law protecting bald eagles – the AP underplayed the significance of hunting and human encroachment and erroneously blamed DDT for the eagles’ near demise.
As early as 1921, the journal Ecology reported that bald eagles were threatened with extinction – 22 years before DDT production even began. According to a report in the National Museum Bulletin, the bald eagle reportedly had vanished from New England by 1937 – 10 years before widespread use of the pesticide.
But by 1960 – 20 years after the Bald Eagle Protection Act and at the peak of DDT use – the Audubon Society reported counting 25 percent more eagles than in its pre-1941 census. U.S. Forest Service studies reported an increase in nesting bald eagle productivity from 51 in 1964 to 107 in 1970, according to the 1970 Annual Report on Bald Eagle Status.
The U.S. Fish and Wildlife Service attributed bald eagle population reductions to a “widespread loss of suitable habitat,” but noted that “illegal shooting continues to be the leading cause of direct mortality in both adult and immature bald eagles,” according to a 1978 report in the Endangered Species Tech Bulletin.
A 1984 National Wildlife Federation publication listed hunting, power line electrocution, collisions in flight and poisoning from eating ducks containing lead shot as the leading causes of eagle deaths. . . .