The American bald eagle (Haliaeetus leucocephalus) is the national bird of the United States and is the only eagle unique to North America. Its distinctive brown body and white head and tail make it easy to identify even from a distance. Bald eagles are not actually bald; the name derives from an older meaning of "white headed". A sea eagle, it has two known sub-species and forms a species pair with the white-tailed eagle (Haliaeetus albicilla). Its range includes most of Canada and Alaska, all of the contiguous United States, and northern Mexico. It is found near large bodies of open water with an abundant food supply and old-growth trees for nesting.