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Size and Weight: Length is about 78-109 cm (33-43 inches). Wingspan is 178-229 cm (70-90 inches). Northern subspecies wingspan may reach up to 7.5 feet making it North America's largest predatory raptor. Weight ranges for males averages 4100 gms (just over 9 lbs) and for females averages 5200 gms (11.5 lbs) although females can weigh up to 14 lbs.
Diet: The bald eagle's diet includes mostly fish, also waterfowl, small to mid-size mammals, and carrion. Studies of nesting bald eagles indicate a diet of 56% fish, 28% birds (mostly aquatic), 14% mammals (seasonally-seem to be least favored) and 2% other but diet varies according to region. Bald eagles often eat carrion when conditions necessitate and will steal food from osprey or other eagles if given the opportunity.
Habitat and Distribution: Bald eagles live near lakes, rivers, and in coastal regions. In winter and while migrating they follow and tend to congregate near open water. They range throughout the 48 contiguous states, Alaska, and Canada. Bald eagles are not considered to be truly migratory although they display considerable seasonal movement with some northern birds moving southward in search of open water and food supplies.
Status in the Wild: On June 28, 2007 the Interior Department took the American bald eagle off the Endangered Species List. This momentus occasion occurs 40 years after the bald eagle was first declared endangered. The bald eagle will still be protected by the Migratory Bird Treaty Act and the Bald and Golden Eagle Protection Act. There are an estimated 4,000 nesting pairs in the lower 48 states (500 in Minnesota and 750 in Florida) for a total of about 13,000 Bald Eagles in that range. An additional 45,000 Bald Eagles are estimated living in Alaska. The world population of Bald Eagles is estimated at about 100,000.
Habits and Adaptations: A powerful and agile flier, the bald eagle flies with its broad wings flat instead of tilted upwards as in vultures. They hunt by perching near water and catching fish with their feet as they surface.
Breeding and Maturation: The bald eagle builds one of the largest nests of any bird species, averaging 5 feet across, 3 feet deep and weighing hundreds of pounds. Large, old trees are most often chosen for nesting for their support and for a commanding view of the surrounding territory. Courtship flights are elaborate and impressive and often include dramatic dives and locking of talons. One to three eggs are laid with most incubation is done by the female for 35 days. If more than one chick hatches, the weaker one(s) often starves or is killed by the other chicks, especially if food is in short supply. Divergence in weight between sexes begins to appear at about 2 months. The young fly at about 11 weeks. White head and tail are acquired over the first five years.
Lifespan: In the wild bald eagles are probably capable of living 20-30 years. The longevity record for a wild bald eagle is 21 years (Weidensaul, 1996) and 48 years for a captive individual (Stalmaster, 1990) They are thought to have a reproductive lifespan of 20-30 years.
Noteworthy: Twelve states include the bald eagle on their official emblems
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