Haliaeetus leucocephalus
(Bald Eagle)

Physical Description:
30-43" (76-109 cm). Distinct white head and neck with a yellow bill. White tail, but otherwise dark brown to black; yellow feet and eyes, which adults take up to 4 years to achieve. The juveniles are dark brown with blotchy white patches under wings and tail, and with huge bill.

Similar Species- Golden Eagle

Song:
Fairly soft pwip-pwip and a faster chitter.

Distribution:
Breeds from central Alaska, east to northern Saskatchewan, Labrador, and Newfoundland, and south, locally, to northern Mexico, New Mexico, Arizona, Texas Gulf Coast, and Florida;very local breeder in interior North America. Winters generally throughout breeding range except in far north.

Diet:

Catches fish (or steals from osprey); also eats various mammals and carrion. Idaho diet includes fish, big game carrion, waterfowl, and jackrabbits.

Ecology
Forages from high altitudes; often forages from perch. Builds stick nest in fork of tall tree, or occasionally on cliff. In winter, adults often roost communally at night, in trees used in successive years. In winter in some areas, adults preferentially roost in conifers, or other sheltered sites, and may associate with waterfowl concentrations, or congregate in areas with abundant dead fish (in Idaho, individuals congregate in numbers on watercourses in northern, eastern, and southwestern parts of state). Montana study determined introduction of shrimp (Mysis relicta) had cascading effect through food chain, ultimately causing displacement of Bald Eagles. North-central Arizona study found February-April home ranges of immatures averaged 400 km2; birds moved frequently and roosted singly or in small groups. Home ranges of Bald Eagles nesting along Cascade Reservoir in west-central Idaho have ranged from 15-60 km2 during breeding season, and have typically been half that size at other times (management recommendations suggest 400 m buffer zone around nest sites to protect key habitat features such as nests, perch trees and food resources). From 1979- 1995, Idaho's nesting Bald Eagle population increased from 11 to 77 occupied territories. In 1995, 51 pairs from occupied territories successfully fledged an average of 1.2 young/pr.

Reproduction:
Both sexes incubate 1- 3 eggs (usually 2) for about 5 wk. Second-hatched young sometimes dies. Young first fly at 10-12.5 wk, remain around nest for several more weeks, and generally do not breed until about 5-6 yr. Adults may not lay every year.

Conservation:

Element Code:	ABNKC10010
U.S. ESA Status:	LTNL
Status:	Protected nongame species
Global Rank:	G4
State Rank:	S3
National Rank:	N4B,N4N

Important State References:
Beals, J., and W. Melquist. 1995. Idaho bald eagle nesting report, 1995. Idaho Dept. Fish & Game, Boise. 23pp.