Animals Wildlife 15 Majestic Facts About the Bald Eagle Did you know eagles can swim and see prey two miles away? By Melissa Breyer Melissa Breyer Twitter Editorial Director Hunter College F.I.T., State University of New York Cornell University Melissa Breyer is Treehugger’s editorial director. She is a sustainability expert and author whose work has been published by the New York Times and National Geographic, among others. Learn about our editorial process Updated August 5, 2022 Share Twitter Pinterest Email KenCanning / Getty Images Animals Wildlife Pets Animal Rights Endangered Species Bald eagles are iconic American birds and the only eagle species unique to and found throughout North America. Vagrant eagles appear on islands in Eastern Russia, Belize, Puerto Rico, and the U.S. Virgin Islands, usually after storms send them off course. The birds and their feathers were sacred to many Indigenous populations long before the bald eagle became the symbol of the newly formed United States in 1782. The eagle is protected under multiple state, federal, and international laws. Due to these protections, eagles are now a species of least concern. From their lazy food gathering habits to their surprising swims, discover more about the bald eagle. 1. Bald Eagles Are Really Large Todd Ryburn Photography / Getty Images Bald eagles are sizable birds, with females reaching 43 inches long with an eight-foot wingspan and weighing about 14 pounds. Males are roughly 25 percent smaller and top out at about 10 pounds. This makes it easy to determine which bird is the female in a couple. Because females are so much larger, they don't maneuver as well in flight. Bald eagles vary in size depending on the region, but Alaskan bald eagles are consistently the largest. Young eagles can appear slightly larger than their parents when they still have their fledgling feathers. These somewhat larger feathers act as training wheels of sorts while the eagle is learning to fly. 2. They Live for a Long Time Up to 80% of eagles die of accidents or starvation before they reach adulthood, but those that do mature—at around 5 years old—typically live for 15 to 25 years. Some have even lived for longer than 30 years in the wild and nearly 50 years in captivity. Despite the often-circulated myth, eagles don't break their beaks and talons off and pluck their old feathers to experience a "rebirth," allowing them to reach 70 years old. This is, in fact, biologically impossible. 3. They Have Complex Relationships With Their Mates Bald eagles that reach adulthood usually mate for life. There are several caveats to that, though. Some have triad partnerships with two males and one female or, more commonly, two females and one male. In these cases, one nest holds the combined eggs, and the birds take care of the eggs and young. Sometimes a territorial dispute results in an eagle breaking up a formed couple. Other times, a couple splits up after failed nesting attempts. If an eagle that is part of a couple dies, the other eagle will take a new mate. 4. They Build Huge Nests LagunaticPhoto / Getty Images Because bald eagles often use the same nest for years, continuously adding to them, their dwellings can get up to nine feet wide and 20 feet deep and weigh two tons, though most reach only about half that size. A couple will start compiling their nest out of large sticks a month or two before mating. These massive wonders can be found at the top of trees with sturdy forked branches near water. 5. They Are Excellent Swimmers Michael-Tatman / Getty Images Eagles are excellent swimmers, though if you see one, you might find them awkward-looking. They use their wings to perform what is essentially a breaststroke. They usually do this when bringing a large fish to the shore. Bald eagles may also swim with their talons clamped around small birds such as geese, though larger fish and waterfowl are their meals of choice. That eagles' talons "lock" on their prey is a myth. 6. They Steal Food Photography is my passion and love / Getty Images Eagles will steal kills from hawks, ospreys, and other eagles, which makes them "kleptoparasitic." This tendency becomes more pronounced when food is scarce. Usually the eagle will chase another bird, such as a gull or another eagle from a lower hierarchy, such as a juvenile one, until it drops its prey and the eagle can snatch it away. 7. They Weren't Benjamin Franklin's Favorite Bird The tendency toward theft is one complaint that U.S. founding father Benjamin Franklin had about the bald eagle. He felt it was a lazy bird because it stole food. But contrary to the popular myth, Franklin didn't suggest the turkey for the Great Seal of the United States and lose out to the bald eagle. He just sent his daughter a letter two years later telling her that it was a disappointing choice. 8. They Are a Conservation Triumph The bald eagle was once nearly extinct, with 487 breeding pairs of birds in 1963. In 2016, researchers estimated there were around 143,000 bald eagles in the United States. A variety of protections, including the Endangered Species Act, created conditions that helped the species rebound. Rachel Carson's book "Silent Spring" inspired changes that reversed the fate of bald eagles. In it, she discussed the damage DDT was doing to bird species, including eagles. DDT was a pesticide that entered the environment when used to prevent mosquitos. Eagles and other birds that ingested the pesticide through water or eating prey species laid thin-shelled eggs that broke in the nest. 9. Wintering Eagles Are Disturbed by Humans Jeff R Clow / Getty Images Wintering eagles find sheltered places to roost, usually in the company of other eagles. While they might attract humans, it's best to give them a wide berth. Human activity alarms them and leads to them looking for new roosts that are not necessarily as safe. They also avoid hunting near humans. The energy expended finding a new place to roost or feed leads to less fit birds in the breeding season. If eagles on the nest are disturbed by activity in the area, the eggs and any young are at risk because they can't maintain a safe temperature. Consult with fish and wildlife officials in the area to learn about safe distances for viewing and other activities. 10. They Have Underwhelming Calls Eagle calls don't match their visual majesty. Their call sounds more like a high-pitched tweet and chatter than the loud scream people imagine. The hungry eaglet cry gets louder as a parent comes closer with food. In general, they have a call that sounds like a much smaller bird, so moviemakers dub in the sound of red-tailed hawks when they are showing a "screaming eagle" on the screen. 11. They Have Excellent Eyesight Eagles do have "eagle eyes." They can see four to five times better than humans. This 20/4 or 20/5 vision gives them the ability to see small prey like rabbits as far as two miles away. Not only can they see great distances, but their vision also stays in focus during rapidly changing depths. When you consider the eagle's flight and hunting style, this vision is necessary to safely fly at 30 to 40 mph and dive at 100 mph. 12. They Hunt a Range of Prey Eagles live near water and primarily eat fish and waterfowl. Fish comprises between 25% and 65% of their diet, but this can vary based on where they live and what is available. When fish is not available, they eat small mammals, like prairie dogs, rats, raccoons, rabbits, domestic kittens, and carrion, as well as livestock, including young pigs, goats, sheep, and free-ranging chickens. 13. Eagles Turn Their Eggs Every Few Hours It takes approximately 35 days for an eaglet to hatch from an egg. During that incubation period, one of the parents will turn the egg every 2 to 4 hours. This prevents the yolk from rising to the surface and causing its delicate blood vessels to stick to the inside of the shell, which could kill the chick. 14. Hatching Is an Exhausting Process Breaking out of an egg is a laborious process for eaglets. It can take them as long as 2 days to emerge, as they need to rest between their bouts of effort. The babies have an egg tooth that they use to scrape and scratch at the shell to weaken it. When the first crack or hole appears, it's called a pip. 15. 'Bald' Actually Means White Their name comes from the Old English word "balde", which means white-headed. It refers to the colors of the feathers on an eagle's head, not the fact that it's hairless. A golden eagle, as you might expect, is named for its golden-yellow head feathers. View Article Sources "Bald Eagle Fact Sheet." United States Fish and Wildlife Service. Watts, Bryan. "Gender Divide in Bald Eagles." The Center for Conservation Biology. 2018. "Learn About Eagles." National Eagle Center. "Haliaeetus leucocephalus: Bald Eagle." Animal Diversity Web. "My two dads: Eagle trio sees parenting success in Illinois." U.S. Fish & Wildlife Service. 2021. "A Rare Bald Eagle Trio—Two Dads and a Mom—Captivates Webcam Fans." National Audubon Society. 2019. "Eagle Diet & Feeding." National Eagle Center. "Let's talk Turkey...and Bald Eagle!" The Peregrine Fund. 2020. "Eagle Management Program" United States Fish and Wildlife Service. Millsap, Brian, et al. 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