In 1963, officials counted just 417 nesting pairs of bald eagles as DDT drove them toward extinction. 44 years later, 9,789 pairs helped secure national symbol delisting

In 1963, the bald eagle was in serious trouble. Only 417 nesting pairs were known to exist, and the species faced a combination of habitat loss, shooting and the effects of DDT. Decades of protection and conservation changed that trajectory. By 2007, officials estimated at least 9,789 nesting pairs in the contiguous United States, helping the nation’s symbol reach a remarkable recovery, as per a report by the U.S. Fish and Wildlife Service.

Why were bald eagles disappearing?

When the bald eagle became the national symbol in 1782, anecdotal accounts suggested there may have been as many as 100,000 nesting eagles in the country. The species began experiencing a major decline during the mid-to-late 1800s as waterfowl, shorebirds and other prey became less abundant.

Bald eagles also faced persecution because they were once viewed as a threat to chickens, lambs and domestic livestock. Large numbers were shot, while the loss and degradation of nesting habitat further reduced their populations.


Congress responded in 1940 by passing the Bald Eagle Protection Act, which prohibited killing, selling or possessing bald eagles. An amendment in 1962 added golden eagles, and the law became the Bald and Golden Eagle Protection Act.

DDT then created another serious problem, as per a report by the U.S. Fish and Wildlife Service.

After World War II, the insecticide was widely used to control mosquitoes and other insects. DDT and its residues reached waterways, where aquatic plants and fish absorbed the chemical. Bald eagles were exposed when they ate contaminated fish.

The pesticide interfered with the birds’ ability to produce strong eggshells. Their eggs could become so thin that they broke during incubation or failed to hatch.

By 1963, only 417 nesting pairs of bald eagles were known to exist, putting the species in danger of extinction.

How did conservation turn things around?

The federal government took additional steps as the threats became clearer. In 1967, bald eagles south of the 40th parallel were listed under the Endangered Species Preservation Act.

In 1972, the Environmental Protection Agency banned the use of DDT and some related pesticides in the United States. The dangers of DDT had become increasingly recognized, in large part through Rachel Carson’s book Silent Spring.

The Endangered Species Act provided another important layer of protection. In 1978, bald eagles were listed as endangered throughout the lower 48 states, with the exception of Michigan, Minnesota, Oregon, Washington and Wisconsin, where they were designated as threatened. Alaska was not included because its bald eagle populations remained robust.

The listing helped accelerate recovery efforts involving captive breeding, reintroduction, law enforcement and protection of nest sites during breeding season.

These measures worked alongside conservation actions taken by the American public and habitat protection provided under federal law.

When did the bald eagle recover?

The recovery became increasingly clear during the 1990s.

In July 1995, officials announced that bald eagle populations in the lower 48 states had recovered enough for those previously classified as endangered to be reclassified as threatened.

The population continued to grow.

By 2007, officials estimated that there were at least 9,789 nesting pairs of bald eagles in the contiguous United States. On June 28, 2007, the recovery of the national symbol was announced, and bald eagles were removed from the list of threatened and endangered species.

The numbers continued rising after delisting. In 2009, the estimated population in the lower 48 states was 72,434 individuals, including 30,548 breeding pairs.

Estimates based on data from 2018 to 2019 put the lower-48 population at 316,700 individuals, including 71,467 breeding pairs.

The bald eagle’s recovery is now regarded as one of the most prominent conservation success stories. Its scientific name is Haliaeetus leucocephalus.

Delisting did not mean the species was left without legal protection. Bald eagles remain protected under the Migratory Bird Treaty Act and the Bald and Golden Eagle Protection Act. Those laws prohibit killing, selling or otherwise harming eagles, their nests or eggs.

The recovery also continues to involve state and federal agencies, tribes, nongovernmental organizations and private landowners.

From just 417 known nesting pairs in 1963 to at least 9,789 pairs in 2007, the bald eagle’s population rebound marked a dramatic reversal for a species that had once been pushed toward extinction.

FAQs

How many nesting pairs remained in 1963?
Officials knew of just 417 nesting pairs.

When were bald eagles delisted?
They were removed from the endangered and threatened species list in 2007.