Bald eagle's successful comeback from near extinction

Tuesday, March 30, 2010

On a clear, cool fall morning, a bald eagle swoops in from its perch on a cliff overlooking Trinity Lake in Northern California. With grace and speed, the eagle flies low over the water and snatches a bass any fisherman would be happy to catch. Chased by three crows, the eagle settles atop a tree, high on the cliff overlooking the water.

This beautiful scene is the result of an amazing comeback story. The majestic bald eagle was adopted as a national symbol in 1782, when there were 100,000 eagles in this country. But 40 years ago, the species had plummeted to near extinction, with just 417 nesting pairs of the birds known in the United States.

After decades of conservation work and successful protection efforts, there are nearly 10,000 nesting pairs nationwide and the birds have been removed from the threatened and endangered species list. If you're lucky, you can sometimes spot a bald eagle around the Chesapeake Bay and local waterways -- sometimes even in the city.

Hunting and loss of habitat were blamed for a decline in the number of bald eagles in the early part of the 20th century, and the federal government responded by creating the Bald Eagle Protection Act of 1940. The possession, selling and killing of eagles were prohibited, but the population continued to decline into the 1960s.

Researchers figured out that a commonly used pesticide, called DDT, was a big part of the problem. Chemical runoff contaminated the fish eaten by the eagles, and the chemicals weakened the eagles' eggshells. Many eggs were damaged before the young could hatch.

That's when a serious effort began to save the bald eagle. The Environmental Protection Agency banned DDT in 1972, and under the Endangered Species Act, it became a crime to disturb the roosting, feeding and nesting sites of a bald eagle.

The other major effort that has brought the eagle back is the reintroduction of the bird to states where it had disappeared. Over 22 years, 103 eagle chicks were hatched and released through a breeding program.

After such a dramatic swing in population, though, no one is taking the eagle population for granted. Wildlife officials will monitor the eagles' numbers for up to 20 years to see if at any point the bird needs to be put back on the endangered list.

-- Staff and wire reports

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