Females are larger than males, and birds of northern states and provinces tend to be larger than those from the southern portions of the breeding range.
Adults are dark brown with a pure white head and tail.
Younger birds are mostly brown, mottled with varying amounts of white. They acquire their adult plumage at 4 or 5 years of age. The range of this raptor is wholly within North America, including Alaska, Canada, the lower 48 states , and northwest Mexico. Bald eagles in winter may be found throughout most of California at lakes, reservoirs, rivers, and some rangelands and coastal wetlands. The State's breeding habitats are mainly in mountain and foothill forests and woodlands near reservoirs, lakes, and rivers.