Eagle Recovery - Status
The Bald Eagle's Status from 1620 to 1967
It is impossible to know exactly how many bald eagles inhabited North America at the time of the first European settlers. However, the U.S. Fish and Wildlife Service stated in a news release of 1999, "When America adopted the bird as its national symbol in 1782, as many as 100,000 nesting bald eagles lived in the continental United States, excluding Alaska."
Revered by native Americans, the bald eagle was sometimes killed for its feathers used in ceremonial headdresses. However, the deep respect native Americans had for the eagle limited the number killed.
When the early settlers arrived, they viewed the bald eagle as vermin and shot them on sight. This wanton killing, in addition to the decline of suitable natural habitat and loss of the food supply (fish, waterfowl, etc.) along shorelines where settlers continued to build and expand, greatly reduced the number of bald eagles.
By 1782, the bald eagle population had already declined substantially from when the first European settlers arrived. Further reductions occurred in the mid-to-late 1800s, starting in the east and progressing westward, coinciding with the movements of the early pioneers. However, as late as the mid-1800s bald eagles were frequently seen by those living on the tiny island of Manhattan in New York and were "extremely abundant on the floating ice of the [Hudson] river" (Gerrard & Bortolotti, 1989)."
The decline of the bald eagle throughout the late 1800s was noted on the western plains and experts speculate that this drop in population could have been due to the decimation of the bison and the complete extinction of the passenger pigeon. Both herds of bisons and flocks of pigeons must have supplied a plentiful food source for the bald eagle at one time.
Further decline resulted from man's deliberate attacks on the bald eagle. Not only did eagles suffer from direct shootings, but the poisoning and trapping of wolves are known to have contributed to the death of many bald eagles.
Due to the killings, loss of food supply, and changes in habitat and suitable nesting sites, bald eagle populations remained low until the 1940s. In 1940, the Bald Eagle Act was passed to provide some protection for the eagle. Increased public awareness of the plight of the eagle and the building of dams and reservoirs throughout the United States allowed the bald eagle population to slowly begin to rebound.
At the height of this recovery, the bald eagle faced its most serious threat to survival: the pesticide DDT. Used safely as a powder disinfectant for U.S. troops in World War II, DDT became a deadly killer when transformed into a spray pesticide. This spray was first used in the south to fight mosquito infestations, but its use became widespread across the country within a short time (Carson, 1962).
From its slow recovery in the 1940s, the bald eagle suddenly plunged into a desperate decline. By 1963, the bald eagle population of the lower 48 states of the union had fallen to a mere 417 nesting pairs of eagles.
In 1962, a former marine biologist and lifelong naturalist, Rachel Carson, chronicled the lethal effects of DDT on bird populations in her landmark book Silent Spring. In the case of bald eagles, the effects of the use of this pesticide took at least a generation to be felt. Since bald eagles live fairly long lives (from 30 to 40 years in the wild and up to 50 years in captivity), small amounts of DDT continued to accumulate in the fatty tissues of the eagle over a long period of time. This process of accumulation, called biological amplification, allowed many eagles to survive for years before dying. However, immediate effects were found on the reproductive capacity of bald eagles that had accumulated significant amounts of the chemical. Calcium production became inhibited in affected eagles which resulted in thin, fragile egg shells which would crack under the weight of the adult eagles (the parents take turns sitting on the eggs to hatch them). Several generations of eagles were lost before the truth of Rachel Carson's words hit home
The Bald Eagle's Status Since 1967
In 1967, the southern bald eagle was listed as endangered under the Endangered Species Preservation Act of 1966. The Southern Bald Eagle was defined as located south of the 40th parallel. The major cause of decline was environmental contamination by the insecticide DDT. Other factors included: habitat loss, disturbance of nest sites, and illegal shooting.
Finally, Carson's long public crusade to eradicate the use of DDT in the United States met with success. In 1972, DDT was banned from use in the United States and in 1973 Congress passed the Endangered Species Act which provided special protection for the bald eagle and many other threatened and endangered species.
The bald eagle has made a significant comeback. In 1995, the bald eagle was downlisted
from Endangered to Threatened in the 43 states where the bald eagle had been
listed as endangered. It was delisted from Threatened status in all 48 continental states in June, 2007, except for the Sonoran Desert Region of central Arizona. It was delisted from Threatened status in all 48 continental states in June, 2007, except for the Sonoran Desert Region of central Arizona. Bald eagle populations will need to
be monitored closely for at least five years after delisting in order that any
needed corrective actions can be taken
Excellent graphics depicting the decline and recovery of the Bald Eagle
have been provided by the US Fish and Wildlife Website and can be found here: http://www.fws.gov/midwest/eagle/population/index.html
Carson, Rachel (1962) Silent Spring. New York: Houghton Mifflin Company.
Gerrard, Jon M. & Bortolotti, Gary R. (1989) The Bald Eagle: Haunts and Habits of a Wilderness Monarch. Washington, D. C.: Smithsonian Institution Press.
The Bald Eagle's Status Since 1967
The nation's symbol, the bald eagle (Haliaeetus leucocephalus), has received a great deal of attention since it was listed as one of the nation's first Endangered Species in 1967. The decline of this magnificent bird was traced to many factors, including habitat loss, disturbance of nest sites, and illegal shooting, but the greatest problem was environmental contamination by the organochlorine pesticide DDT.
With the banning of DDT in 1972 and the efforts of federal, state, and private agencies to protect eagles and their habitat, the species' numbers have increased from an estimated 417 nesting pairs in 1963 to over 2,660 nesting pairs in 1989. Currently, the eagle is listed as "threatened" in the lower 48 states.
In four of the five bald eagle recovery regions in the United States (i.e., Pacific Northwest, Southwest, Northern States, and Chesapeake Bay), the eagle has reached the goals in the respective recovery plans for reclassification from endangered to threatened. Eagle populations also have increased in the fifth recovery region, the Southeast, although the distribution of eagles over the 12 States involved is not yet satisfactory.
With the dramatic increase in bald eagle numbers, the Fish & Wildlife Service believes it is time to conduct a comprehensive review of the species' status and determine whether or not it should be proposed for reclassification from endangered, to the less critical threatened category throughout its range. Before proposing such a change, however, the Service wants to be sure that it has the most up-to-date information available. Consequently, a notice of intent was published in the February 7, 1990, Federal Register to solicit additional information. The Service will review comments on this notice and the 1990 bald eagle breeding data before deciding on a reclassification proposal.
It is important to emphasize that the Service is not considering removing the bald eagle from the Endangered and Threatened Species List. Even if the species is reclassified to Threatened, bald eagles and their habitat would continue to receive protection under the Endangered Species Act, as well as two other Federal laws, the Eagle Protection Act and the Migratory Bird Treaty Act. Anyone taking, attempting to take, or otherwise illegally possessing a bald eagle or eagle products without a permit would be subject to the same penalties now in force. Section 7 of the Act also would continue to protect this species from Federal actions that could jeopardize its survival. The Service will continue to work with Federal and State agencies and private groups to seek full recovery of the bald eagle.
Bald eagles in Alaska and Canada, where the species is considered relatively plentiful, are not listed as endangered or threatened. They are protected, however, by the Migratory Bird Treaty Act and, in Alaska, also by the Eagle Protection Act.
Decline of the Eagle
One of the first naturalists to record the dramatic decline of the bald eagle after the introduction of DDT as a pesticide spray was a Florida naturalist named Charles Broley. Broley had been observing and banding bald eagles for years when in 1947 he voiced concern about the reproductive rate of the bald eagle. At that time, few records on bald eagle populations were kept. Therefore, Broley's records tracing the number of nesting bald eagles in Florida provided some of the first evidence that the bald eagle population was declining at an alarming rate.
The chart above illustrates Broley's findings regarding the bald eagle population in Florida. The trend in this chart was verified around the country and in 1963 the Fish & Wildlife Service recorded the dismal figure of only 417 nesting pairs of bald eagles in the entire lower 48 states of the United States of America. Our national symbol reached the verge of extinction before the country took notice and attempted to determine what was happening to the bald eagle. The culprit turned out to be a combination of factors, the most serious being the chemical pesticide DDT.
Bald Eagle Recovery
The most accurate data on the recovery of the bald eagle population in the United States are taken from sightings of nesting pairs. Based on figures from the U. S. Fish & Wildlife Service, the table below illustrates the increase in the number of bald eagle nesting pairs in the continental U. S. from 1963 through 2006.
Between the early 1980s and 2000, most States conducted annual bald eagle surveys. Since then, many states recognized that annual surveys were no longer necessary. That is why you will not see annual data after 2000.
In 1963, only 417 nesting pairs could be found in the lower 48 states. As noted in the above table, the U.S. eagle population has steadily increased since that time to approximately 9,789 nesting pairs in 2006.
Current Status of the Bald Eagle
On August 11, 1995 the Fish & Wildlife Service reclassified the bald eagle
(Haliaeetus leucocephalus) from endangered to threatened in the lower 48
states under the Endangered Species Act of 1973 (Act). The bald eagle remained
classified as threatened in Michigan, Minnesota, Wisconsin, Oregon, and Washington.
This action did not change those conservation measures already in force to
protect the species and its habitats. The bald eagle also occurs in Alaska
and Canada where it is not a risk and is not protected by the Act.
Laws affecting Bald Eagle protection were changed after the bald eagle
was delisted from Threatened status on June 28, 2007. After no longer being
protected by the Endangered Species Act, protection of Bald Eagle and its
habitat is enforced under the provisions of the Bald and Golden Eagle Protection
Act (BGEPA). The penalties under either Act can be as high as $100,000
for individuals and $200,000 for organizations. Eagles are not allowed
to be "disturbed" under the BGEPA. However, since "disturb" was previously
not defined in the Act, the new definition of disturb is:
Disturb means to agitate or bother a bald or golden eagle to a degree that
causes, or is likely to cause, based on the best scientific information
available, 1) injury to an eagle, 2) a decrease in its productivity, by
substantially interfering with normal breeding, feeding, or sheltering
behavior, 3) nest abandonment, by substantially interfering with normal
breeding, feeding, or sheltering behavior.
The U.S. Fish and Wildlife Service (USFWS) has developed the, "National
Bald Eagle Management Guidelines". They are not the law in themselves,
but are designed to help everyone judge what would constitute eagle "disturbance", under the provisions of the BGEPA. These guidelines can be found by accessing the USFWS web site: http://www.fws.gov/midwest/eagle/guidelines/index.html.