Ecology of Bald Eagles in the Greater Yellowstone Ecosystem
Swenson JE, Alt KL, Eng RL. 1986. Ecology of Bald Eagles in the Greater Yellowstone Ecosystem. Wildlife Monographs. 95:3 - 46
The ecology of the bald eagle (Haliaeetus leucocephalus ) was studied from 1972 to 1982 in the Greater Yellowstone Ecosystem in northwestern Wyoming and adjacent Idaho and Montana. This population consisted of 3 ecologically, but not genetically, distinct units: the Yellowstone Unit (YU), the Continental Unit (CU), and the Snake Unit (SU). The population probably was stable at 30-31 breeding pairs from 1960 to 1970, but increased exponentially to 50 known breeding pairs from 1971 to 1982. Breeding bald eagles were adaptable in selecting breeding areas. A stable food source, which was available from early spring, appeared to be the most important factor in breeding area selection. There were 50-58 breeding pairs and a total of 180-210 bald eagle in this population in autumn 1982. Spraying of DDT for forest insect control between 1955 and 1963 apparently depressed reproduction, recruitment and population levels in sprayed areas.
- Type
- Journal Article
- Authors
- Swenson, Jon; Alt, Kurt; Eng, Robert
- Units
- GRTE , YELL
- Keywords
- Animal Studies, Bald Eagle (Haliaeetus leucocephalus), Birds, Breeding, Distribution, Ecology, Ecosystems, Feeding, Food, Greater Yellowstone Ecosystem, Nests and Nesting, Population, Raptors, Reproduction