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About Bald Eagles
Johnson City EagleBald Eagle
Haliaeetus leucocephalus

The Bald Eagle is the United States' national bird and is an easily recognizable species even to the casual observer. No other bird has a bright white head and tail with a massive yellow bill. Bald Eagles belong to the family Accipitridae, which also includes hawks, kites, harriers, and Old World vultures. The scientific name roughly translates to "White-headed Sea Eagle," which is appropriate because these birds are almost always nesting around water.

At the time the cameras were erected, Our Johnson City nest had been used for 3 years and our Bluff City nest had been used for 4 years, and you can see how enormous they already are! Eggs are hatched in about a month's time, and nestlings remain in the nest for 2-3 months. Young Bald Eagles appear all dark with their dark bill and a mottled mix of brown and white plumage. It typically requires 4-5 years before the young develop the characteristic yellow bill with white head and tail of an adult.

Nidification and the Young- Bald Eagles mate for life and show high fidelity to the same nest. They build truly impressive nests, where they can lay up to three dull-white eggs per breeding season. As part of their courtship ritual, mated pairs of Bald Eagles bring nesting material in the form of twigs and branches to the same nest year after year. An adult Bald Eagle can nest once a year for more than three decades, so the nests can potentially weigh well over a ton!

Diet- You can gain information about what a bird eats by examining its bill. Bald Eagles with their strongly hooked bill are chiefly piscivorous, fish eaters, but they will not pass up an easy meal. Bald Eagles can be seen eating carrion and the occasional small mammal or bird.

Size­- As in other birds of prey, Bald Eagle females are about a third larger than their male counterparts. A large female may have a wingspan of nearly 7 feet and weigh as much as 14 pounds! Males by comparison have a wingspan 5 ½ -6 feet and weigh 10-12 pounds. Bald Eagles from northern populations are larger than those from southern populations, an ecological principle known as Bergmann's Rule.

Habits- Courtship displays in Bald Eagles are fascinating. The pair will join talons at great heights and spiral downward, only separating at the last instant before inevitable impact. Northern populations of Bald Eagles tend to be migratory to escape harsh winters, whereas our East Tennessee Bald Eagles are permanent residents. These birds can be seen soaring on thermals, rising columns of warm air, in search of their favorite meal of fish.

Longevity- Bald Eagles in the wild typically live around 20 years, with the oldest one on record being 38 years old. Captive birds can live longer. One Bald Eagle in a zoo in West Stephentown, NY lived to be 48 years old! Many factors can affect wild Bald Eagles' lifespan, including: vehicle collisions, power line and fishing line entanglements, gunshot, famine, poisoning by ingesting lead shot, and disease.

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