ABSTRACT
The bald eagle, Haliaeetus leucocephalus, occurs throughout the North American continent, principally in association with undisturbed sea coasts, productive lakes, and rivers. Highest densities of breeding populations are found along the Pacific Coast from Alaska to northwestern Washington, central Canada, Great Lake states, Florida, and eastern Canada. Bald eagles attain their adult plumage of white head and tail feathers at the age of 4 or 5 years. The subadult plumage varies from dark brown to mottled white and brown. When the birds are almost adult, they have nearly white head and tail feathers, with slight mottling or streaking of brown. During incubation period and the first 3 weeks following hatching, one or both breeding adults will likely be on nest platform. Bald eagles can be counted by fixed-wing aircraft or helicopter during the period of the day when they are feeding. Fly the shoreline or riverbank at about 75-m elevation and 50 m offshore, depending on the terrain and conditions.
