for National Geographic News
Two hundred and twenty years agoon June 20, 1782the bald eagle became an American icon when the Second Continental Congress decided to use its image on The Great Seal.
The Congress had considered another birdnot the wild turkey championed by Benjamin Franklin, but a fanciful eagle inspired by the imperial eagle of the Eastern Hemisphere. In altering the earlier design, Charles Thomson, secretary of the Congress, substituted the native bald eagle suspended on spread wings, "to denote," he said, "that the United States of America ought to rely on their own Virtue."
Incensed by the decision, Ben Franklin would become the bald eagle's greatest detractor. Viewing the national bird through overly anthropomorphic spectacles, he judged it immoral because it pirated fish from the osprey, cowardly because it retreated from the aggressive, yet comparatively small, Eastern kingbird.
Time, of course, would prove Franklin wrong. In the minds of many Americans, North America's second largest bird of prey (after the California condor) is a fitting symbol for a republic founded on lofty democratic principles. Its image graces currency, stamps, art, architecture, and corporate logos. As the subject of more than 2,500 published papers and books, the bald eagle, moreover, is probably the most extensively studied North American bird.
Settlers Saw Bird as a Competitor
Attitudes like Franklin's, however, prevailed for the eagle's first 175 years as the national bird. To settlers, the eagle's seven-foot (two-meter) wingspan, fierce gaze, and crushing talons symbolized a competitor bent on depriving them of fish and game, and on depleting their livestock. They also killed eagles for sport. Meanwhile, Native Americans trapped and killed eagles to obtain ceremonial feathers.
While shooting, trapping, and poisoning took their toll, human population growth and land-clearing along navigable rivers and estuaries destroyed prime eagle habitat. Before European settlement, 250,000 to 500,000 bald eagles ranged across North America, and as late as the mid-1800s, wintering eagles reportedly fished the waters off New York's Manhattan Island by the hundreds, sometimes devouring their catch in Central Park.
"The relationship between human development and the absence of bald eagles has been documented in various places across the country," said David A. Buehler, author of the bald eagle monograph in the recently published Birds of North America: Life Histories for the 21st Century.
"In general," Buehler added, "eagles avoid developed areas, where their risk of mortality rises. Shooting, trapping, poisoning, collisions with man-made structures, scarcity of prey, and poor nesting and roosting habitat are among the dangers. I think it was the human persecution, however, that ultimately 'taught' eagles in an adaptive sense to avoid people."
With the westward expansion of human settlements, persecution and habitat destruction whittled away at eagle numbers. By 1940, the bird's rarity compelled Congress to pass the Bald Eagle Protection Act, which outlawed the killing and disturbing of eagles, as well as the possession of eagle parts, including feathers, eggs, and nests.
More Than 150,000 Slaughtered in Alaska
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