Bald Eagle

Both male and female adult bald eagles have a blackish-brown back and breast; a white head, neck, and tail; and yellow feet and beak.
Juvenile bald eagles are a mixture of brown and white; with a black beak in young birds. The adult plumage develops when they are sexually mature. It takes about five years for their head and tail feathers to gradually turn white.
Some bald eagles have leucism, a genetic mutation that affects feather pigment. A leucistic bald eagle can have patches of white feathers on its body and wings; have overall faded or pale feathers; or have overall white feathers. Examples: patches of white feathers and pale feathers
The bald eagle is the only eagle confined to North America. There are no other large blackish-brown birds with a white head and tail in North American.

http://www.baldeagleinfo.com/