HABITAT: Bodies of water with large trees nearby and some freedom from disturbances while nesting.

SIZE: LENGTH: 34-43 inches
WINGSPAN: 6-7.5 feet
WEIGHT: 4.4-13.6 pounds

LIFE EXPECTANCY:
WILD: 50-60 years
CAPTIVITY: Unknown

REPRODUCTION: Pick largest tree in a stand of trees near water, with an open view of area. Nest trees are usually less than 1 km from water. Require freedom from human disturbance in order to nest. Nest are built on average 25 m (82 ft) from ground. Nest on sea stacks, peninsular ridges, islets, or hillsides which provide height and isolation in coastal Alaska and Aleutian Islands where there are no trees. Lay eggs between October (southern parts of range) and May. Lay 2 eggs 2-4 days apart. Northern populations have laid 3 or 4 eggs in a nest rarely. Incubation period of 35 days. Both sexes incubate, with female doing more of the work. Young stay in nest 10-12 weeks and are brooded closely at first, then are increasingly left alone while parents hunt for food. Successful fledging of 2 chicks occurs only 3-35% of time.

DIET:
WILD: Fish primarily; birds such as ducks and gulls; mammals such as rabbits, hares, rats, and sea otter pups; carrion

BEHAVIOR: Prolonged period of immaturity. They mature at around 5 years of age though 4 year olds have been known to breed. A large number of adults are non-breeders, probably due to competition within the species and variable annual food supply. Southern population is sedentary and probably maintains pair bonds throughout the year. Northern population is migratory and pairs probably separate during winter. Aerial displays include talon locking and spinning descents, pursuit flight, and gyrating sky dancing. Copulation occurs on tree branches or some sort of support.

POINTS OF INTEREST: Bald eagles hunt cooperatively, usually when hunting mammals such as rabbits. Distinctive white head and tail in adults. They have 4 methods of catching fish: 1) swooping from perch, 2) swooping from flight, 3) wading from shore and catching prey with talons or beak, 4) and standing at edge of ice catching prey with talons or beak. Can catch fish up to 3 kg (6.6 lbs). The largest fish may be brought to shore by alternating periods of towing or flying with prey for short distances and resting half submerged on water. Juvenile birds have slightly longer wings and tails than adults. When gliding or soaring, wings are held horizontally, unlike golden eagle or turkey vulture which hold wings at an uptilted angle (dihedral).

STATUS: Bald eagles declined sharply in southern populations during 1950's due to effects of DDT on reproduction and loss of habitat. With ban on DDT in 1972 and help from humans, bald eagle numbers have risen to a point where they have been taken off the endangered species list.

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