Bald Eagle
The bald eagle (Haliaeetus leucocephalus), one of North America's largest birds of prey with a wingspan of up to 7.5 ft (2.3 m), is a member of the family Accipitridae. Adult bald eagles are dark brown to black with a white head and tail; immature birds are dark brown with mottled white wings and are often mistaken for golden eagles (Aquila chrysaetos). Bald eagles feed primarily on fish, but also eat rodents, other small mammals and carrion. The bald eagle is the national emblem for the United States, adopted as such in 1782 because of its fierce, independent appearance. This characterization is unfounded, however, as this species is usually rather timid.
Formerly occurring over most of North America, the bald eagle's range—particularly in the lower 48 states—had been drastically reduced by a variety of reasons. One being its exposure to DDT and related pesticides, which are magnified in the food chain/web. This led to reproductive problems, in particular, thin-shelled eggs that were crushed during incubation. The banning of DDT use in the United States in 1972 may have been a turning point in the recovery of the bald eagle. Eagle populations also were depleted due to lead poisoning. Estimates are that for every bird that hunters shot and carried out with them, they left behind about a half pound of lead shot, which affects the wildlife in that ecosystem long after the hunters are gone. Since 1980, more than 60 bald eagles have died from lead poisoning. Other threats facing their populations include habitat loss or destruction, human encroachment, collisions with high power lines, and shooting.
In 1982 the population in the lower 48 states had fallen to less than 1,500 pairs, but by 1988 their numbers had risen to about 2,400 pairs. Due to strict conservation laws, the numbers have continued to rise and there are now 6,000 pairs. On July 4, 2000, the bald eagle was removed from the Endangered listing and is now listed as Threatened in the lower 48 states. The bald eagle is not endangered in the state of Alaska, since a large, healthy population of about 35,000 birds exists there. During the annual salmon run, up to 4,000 bald eagles congregate along the Chilkat River in Alaska to feed on dead and dying salmon.
Bald eagles, which typically mate for life and build huge platform nests in tall trees or cliff ledges, have been aided by several recovery programs, including the construction of artificial nesting platforms. They will reuse, add to, or repair the same nest annually, and some pairs have been known to use the same nest for over 35 years. Because the bald eagle is listed as either endangered or threatened throughout most of the United States, the federal government provides some funding for its conservation and recovery projects. In 1989, the federal government spent $44 million on the conservation of threatened and endangered species. Of the 554 species listed, $22 million, half of the total allotment, was spent on the top 12 species on a prioritizedlist. The bald eagle was at the top of that list and received $3 million of those funds.
Bald eagle (Haliaeetus leucocephalus). (Photograph by Robert J. Huffman. Field Mark Publications. Reproduced by permission.)Resources
Books
Ehrlich, P., D. Dobkin, and D. Wheye. Birds in Jeopardy. Stanford, CA: Stanford University Press, 1992.
Temple, S., ed. Endangered Birds: Management Techniques for Preserving Threatened Species. Madison: University of Wisconsin Press, 1977.
Periodicals
Dunstan, T. C. "Our Bald Eagle: Freedom's Symbol Survives." National Geographic 153 (1978): 186–99.
Organizations
American Eagle Foundation, P.O. Box 333, Pigeon Forge, TN USA 37868 (865) 429-0157, Fax: (865) 429-4743, Toll Free: (800) 2EAGLES, Email: EagleMail@Eagles.Org., <http://www.eagles.org>
This is the complete article, containing 601 words
(approx. 2 pages at 300 words per page).
