Still Threatened, Bald Eagles Making A Comeback

More than 4,000 nesting bald eagle pairs exist in the lower 48 states, the U.S. Fish and Wildlife Department says. In 1963 a national survey found only 417 nesting pairs.

Historically, bald eagles nested throughout most of North America, including 45 of the lower 48 states. One estimate suggested that there were 250,000 bald eagles in North America before 1800; by 1900 the birds were already in decline.

By 1940, habitat loss and unrestricted shooting prompted Congress to pass the Eagle Protection Act, prohibiting the killing and selling of bald eagles. Their population, however, continued to decline as widespread use of DDT after World War II caused the contaminant to build up in the birds’ food chain, resulting in reproductive failure.

The bald eagle was declared an endangered species first in the southeastern United States in 1967, then in most of the lower 48 states in 1978. In Alaska, the bald eagle population has stabilized at about 30,000 birds.

The most significant event in the bald eagles’ recovery came on Jan. 1, 1973, when DDT was banned in the United States. It wasn’t until 1986, however, that eagle numbers began to increase.

Despite major gains, there remain significant problems blocking further recovery.

In the Great Lakes, the Columbia River estuary and Maine, concentrations of DDT/DDE, dieldrin, dioxin and PCBs are still being found in the tissues of both young and adult bald eagles.

These contaminants are causing low reproduction rates and fetal deformities among the bald eagles in those areas.

In addition, habitat loss is still a major deterrent to the continuing recovery of eagle populations. That is why bald eagles in Arizona, New Mexico, western Texas and a small portion of southeastern California will continue to be classified as endangered, even though the bald eagles were moved to the less serious threatened list last summer.

Bald eagles may live for 25 to 30 years in a healthy environment, migrating in winter to communal gathering places where food - consisting mostly of fish - is plentiful, and to breeding grounds in summer to produce future generations.

MEMO: This sidebar appeared with the story: THE BALD TRUTH Bald eagles have steadily gained numbers in the Idaho Panhandle since the Idaho Fish and Game Department recorded the region’s first nest in 1978. Last year, the department monitored 22 active nests in the Panhandle and discovered four new nests. Those 26 nests produced 26 bald eagle chicks. In January the department counted 174 eagles flying in from the north to winter in the area. For the past 20 years, an average of 3 percent more eagles have wintered in the Panhandle each year. -Idaho Fish and Game