Eagles are the largest bird of prey in North America. When hatched, eaglets have thick, light-colored down that is replaced with dark feathers within 5 to 6 weeks. Eagles have long sharp talons by which they capture and kill prey animals. The tarsi (lower legs) are feathered to the toes on golden eagles but are bare on bald eagles.

Golden eagles weigh from 7 to 13 pounds (3 to 6 kg) as adults and have a wingspread of 6 to 7 1/2 feet (1.8 to 2.3 m); females are about one-third larger than males.

The plumage color of golden eagles changes with age. Birds in their first year are predominantly dark brown, with considerable areas of white on the underside of their wing flight feathers. The tail has a broad white band with a dark terminal band at the tip. The back of the neck may or may not appear gold or bronze, depending upon light conditions and the individual bird. This color is what gave the golden eagle its common name. Adult eagles are dark brown or bronze.

Bald eagles weigh from 9 to 15 pounds (4 to 7 kg) as adults and have a wingspread of 7 to 8 feet (2.1 to 2.4 m). As in golden eagles, females are about one-third larger than males.

Bald eagle plumage color also changes with age. Juvenile bald eagles generally are mottled brown or nearly black and resemble adult golden eagles. These juveniles have no distinct white patches. Their tail and wings are mottled brown and white on the underside in contrast to the characteristic white patches under the wings and the white-banded tail of juvenile golden eagles. Although adult bald eagles of both sexes have the white head and tail, they do not develop these characteristics until they are 4 to 5 years of age or older.

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Eagles