Despite their feeding habits, bald eagles are graceful and fascinating creatures. At 5 years old, these birds seek a lifelong partner by performing courtship calls and aerial displays, including a cartwheel maneuver known as the death spiral. The spectacle begins at a high altitude as the eagles lock their talons while tumbling down, breaking apart just before hitting the ground. The dangerous display exhibits the fitness levels of the eagles, a factor in choosing a partner.
Once coupled, the eagles build their nests, called aeries, atop large, sturdy trees to ensure the safety of their eggs. Both males and females gather materials such as sticks, grass and cornstalks to build the nest, but the female does most of the arranging. Together they build some of the largest and heaviest bird nests — usually 6 feet in diameter and 4 feet tall — typically taking nearly three months to finalize. They live near rivers and lakes where they can find fish, a primary food source.
The female lays one to three eggs in that big nest. Eaglets hatch about 35 days later; they’re nearly full grown at 9 weeks. Their longer, darker feathers and lack of white markings distinguish them from adults. At 4 or 5 years old, they develop the characteristic bald eagle features.
Bald eagles have a wingspan of 6 to 8 feet, allowing them to dive at speeds of 75 to 100 mph and soar more than 10,000 feet high. Immature eagles will spend their first few years roaming, traveling hundreds of miles each day. They can spot prey up to a mile away and will capture it in a quick swooping motion, clasping it with their talons. Bald eagles can float and use their wings to “row” through deeper water, an advantage when catching fish.
The bald eagle was one of the first species to be declared endangered. Once thriving, the bird declined in numbers in the middle of the 20th century because of illegal shootings, habitat loss and pesticide poisoning. In 1963, only 417 nesting pairs were located throughout the lower 48 states, a significant drop compared to the estimated 100,000 pairs in the late 1700s. In an effort to save the bird, conservation laws were passed, and eagles were placed in captive breeding programs. In 1972, the Environmental Protection Agency banned the use of the chemical DDT throughout the country.
Their recovery is now a success story. Nearly 10 years ago, the bald eagle was removed from the endangered species list and is currently listed as a species of least concern on the International Union for Conservation of Nature (IUCN) Red List. Although they have made a comeback, bald eagles are still vulnerable to threats posed by environmental pollution, human disturbance and habitat loss. But with the assistance of conservation efforts, bald eagles can live to be more than 35 years old.