Northern Prairie Wildlife Research Center
Federally Listed Endangered, Threatened, and Candidate Species 1995
Bald Eagle (Haliaeetus leucocephalus)
- Official Status: Endangered (North Dakota)
- Endangered species are species that are in danger of extinction throughout all or a significant portion of their range. It is unlawful to kill, harm, or harass endangered species.
- 43 Federal Register 6233; February 14, 1978 (North Dakota and 42 other states)
- Historical Status:
- Bald eagles are thought to have
historically nested in all of the lower 48 states. In North Dakota, bald eagles were apparently common along the Missouri and Red Rivers, and at Devils Lake and the Turtle Mountains. It's estimated that in the lower 48 states there were 50,000 breeding pairs of bald eagles in pre-colonial times. Due to human activities, the population in the lower 48 states reached a low of 400 breeding pairs in the early 1960's.
- Present Status:
- Bald eagles are abundant in Alaska
and Canada. In 1990, there were approximately 2,500 breeding pairs in the lower 48 states. In 1988, the first bald eagle nest in North Dakota since 1975 was documented. The nest was along the Missouri River in McLean County. A single-active nest was also reported in 1989, 1990, and 1991. Major wintering areas for bald eagles are along the lower reaches of the Mississippi, Missouri, and Illinois River systems, Florida and the Pacific coast. In recent years, an average of 45 eagles have wintered below the Garrison Dam.
- Bald eagles prefer forested habitats near bodies of water. Eagles concentrate near open water in the wintertime. The tailrace of the Garrison Dam provides this habitat. Migrating eagles are found throughout North Dakota.
- Life History:
- Sexual maturity for eagles is reached at
4 to 6 years of age. Adults mate for life and tend to use the same nest year after year. The majority of nest sites are within 1/2 mile of water. Nests are usually at the top of tall trees, although cliffs are occasionally used. Nests can become enormous, weighing more than a ton. Usually 2 eggs are laid in a clutch. The eggs hatch after 35 days of incubation. Both parents assist in feeding the young. Young leave the nest after 75 days. Bald eagles feed on fish, waterfowl and other birds, small mammals, and carrion.
- Aid to identification:
- The white head and tail of
mature bald eagles is an identifying characteristic. Immature birds are more difficult to identify. They are predominately brown with an increasing amount of white mottling as the bird matures. The wingspan of 7 feet tends to distinguish the young birds from all other birds except the golden eagle.
- Reasons for decline:
- Bald eagle populations
declined in the early 20th century due to loss of habitat, shooting, and trapping. During the 1950's and 1960's the use of pesticides, especially DDT, became a major problem. DDT residues accumulated in fish, a major food source of eagles. The residues then accumulated in the eagles that ate the fish and subsequently caused a thinning of the eggshells. DDT is now banned in the United States. Shooting, trapping, poisoning, and human disturbance continue to be a problem. Bald eagles can be electrocuted when perching on powerlines.
- Buffer areas of 1 mile from an
active nest should be created. There should be no human activity within this buffer area during the breeding season. Wounded or sick eagles should be reported immediately to a wildlife agency. There are many rehabilitation centers throughout the country that can care for eagles.
- In addition to being protected by the
Endangered Species Act of 1973, the bald eagle is also protected by the Bald Eagle Protection Act of 1940. The bald eagle is the national symbol ot the United States. The recovery goal for the bald eagle in North Dakota is to have 10 active nests by the year 2000.
- Northern States Bald Eagle Recovery Plan
by U.S. Fish and Wildlife Service, 1983.
Previous Species -- Least Tern
Return to Contents
Next Species -- Whooping Crane