A fierce demeanor, a distinctive white head and tail, and a wingspan of up to 8 feet endow the bald eagle with a majesty that few wild animals can equal. Add to this a range restricted to North America, and it is fitting that, in 1782, this bird was adopted as the national symbol of the United States. Yet from that time forward the bald eagle has been buffeted by ill winds.
"He is a bird of bad moral character," Benjamin Franklin said in a 1784 letter to his daughter, referring to the eagle's occasional practice of stealing fish from the osprey. Because even the small kingbird seemed to attack the eagle without fear of reprisal, Franklin branded the national bird "a rank coward."
Franklin betrayed a common prejudice against raptors, one that would persist for 150 years. Through the 1800s, the bald eagle's symbolic status did little to protect it from persecution by farmers, ranchers and hunters. They viewed the eagle as a threat to their livestock, as a competitor for fish and game, and as a tempting target. Sure, they might have stopped to admire a soaring eagle. But then they reached for their guns.
Meanwhile, the march of human progress was encroaching on the eagle's territory. Bald eagles thrive in remote settings, where they use towering trees for nesting and pristine waters for catching or scavenging fish. Fish are their main food, but they also eat waterfowl, carrion and small mammals. Developing towns and cities, often situated along rivers and estuaries, drove eagles away from what had been prime habitat. Eagles also suffered because of declines in prey species, attributable to pollution and other human activities.
By 1940, bald eagle numbers had decreased to the point where Congress feared the species was in danger of extinction. The Bald Eagle Protection Act made it a crime to kill, disturb or trade in the national bird. (Federal and many state laws now protect other raptors.) In 1952, after studies proved eagle predation did not threaten salmon populations, this law would end a longstanding bounty system in Alaska that had provoked the killing of more than 100,000 bald eagles.
Elsewhere, however, any gains resulting from this law evaporated soon after World War II. DDT, a widely used insecticide, had entered the eagle's food chain.
DDT accumulates in female birds and blocks calcium formation. Bald eagles and other species were failing to reproduce because the shells of the eggs they laid were too thin. Wildlife experts estimate that as many as half a million bald eagles ranged across North America when European settlers arrived here. A survey in 1963 of bald eagles nesting in the lower 48 states found only 417 pairs.
Largely because of Rachel Carson and her landmark book, "Silent Spring," DDT was banned in the United States in 1972. The following year, Congress passed the Endangered Species Act, which in 1978 listed the bald eagle as endangered in 43 of the lower 48 states and as threatened in the remaining five.
Aided by conservation groups and a concerned public, federal and state wildlife agencies enforced the act and developed recovery programs. By 1994, there were some 4,450 pairs of bald eagles nesting in the lower 48 states, an increase of more than tenfold from 20 years earlier.
The eagle's comeback prompted the U.S. Fish and Wildlife Service to reclassify the species in the 1995 as threatened rather than endangered in the lower 48 states (the nearly 50,000 bald eagles in Alaska are not protected under the act because they are not at risk). Although this change meant eagles were no longer in danger of extirpation, it did not weaken measures in place to protect the bird and its habitat.
As their numbers grow, bald eagles can be expected to expand their breeding range in the Northeast, within limits imposed by habitat destruction, human disturbance and environmental contamination.
Pub Date: 5/03/98