Adult bald eagles (at 4 to 5 years) are identified by their white head and tail, solid brown body, and large, curved, yellow bill. Juveniles have blotchy patches of white on their underside and tail. Adults are about1 m (3 ft.) in height and have a 2.3 m (7 ft.) wing span. Male eagles weight 3.5 to 4 kg (8-9 lb.) while females range from 4.5 to 6 kg (10-14 lb.).
The bald eagle is not really bald; it actually has white feathers on its head, neck, and tail. Bald is a derivation of balde, an Old English word meaning white. The eagle was named for its white feathers instead for a lack of feathers.
Bald eagles in Alberta live and nest near rivers, lakes, and wet prairies. Eagles will take fish swimming close to the water's surface, small mammals, waterfowl, wading birds, or carrion.
Bald eagles can live up to 30 years in the wild and longer in captivity. The bald eagle can fly 20 to 40 mph in normal flight and can dive at speeds over 100 mph. These eagles can also actually swim, and will use an overhand movement of the wings that is very much like the butterfly stroke.
Bald eagles reach sexual maturity at the age of 4 to 5 years and may use the same nest year after year, adding more twigs and branches each time. One nest was found that had been used for 34 years and weighed over two tons! The female will lay 2 or 3 white eggs and incubation will last 30 to 45 days.
© 2001 University of Alberta Museum of Zoology