Animals Wildlife 10 Majestic Facts About the Beautiful Bald Eagle By Melissa Breyer 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. our editorial process Melissa Breyer Updated December 28, 2020 KenCanning / Getty Images Share Twitter Pinterest Email 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 U.S. Virgin Island, 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 Andy Morffew / Flickr / CC BY 2.0 Bald eagles are sizeable birds, with females reaching 43 inches long with an 8-foot wingspan. Males are about 25 percent smaller and top out at about 10 pounds. Females can weigh up to 14 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. There are regional differences in bald eagle sizes, with Alaskan bald eagles consistently the largest birds. 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 Bald eagles sometimes live for more than 30 years in the wild. A more typical lifespan for an eagle that reaches adulthood is 15-25 years, which is still a lot for a bird. Unfortunately, up to 80 percent of eagles don't reach adulthood. Despite the often-circulated myth, eagles don't break their beaks and talons off and pluck their old feathers to experience a "rebirth," so they may live to age 70. This is biologically impossible. In captivity, they have reached 47 years with proper nutrition and veterinary care. 3. They Mate for Life Bald eagles that reach adulthood usually mate for life. There are several caveats to that, though. Some bald eagles 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 Bald eagles often use the same nest for years, sometimes expanding to 9 feet wide and 20 feet deep and weigh two tons. It generally is half that size, and the parents start building the nest out of sticks one to two months before mating. Look for eagle nests at the top of trees with sturdy forked branches near water. If you spot a bald eagle nest, check with your state fish and wildlife commission to let them know the location. Stay far away from any nesting eagles to avoid disturbing them. 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 they have grabbed a large fish and are close to shore. Swimming with birds such as arctic loons and geese in tow also occurs if lifting back off is difficult. Even though this is generally done with larger fish and waterfowl, it is a myth that the talons "lock" on the prey, and it is a literal sink or swim situation. 6. They Steal Food Photography is my passion and love / Getty Images Eagles live near water and primarily eat fish and waterfowl. They also eat small mammals like prairie dogs, rats, raccoons, rabbits, and carrion. They will steal kills from other animals, like hawks, ospreys, and other eagles. This theft is one complaint 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. 7. 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. 8. Wintering Birds 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 about their recommendations for safe distances for viewing and other activities. 9. 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. 10. They Have Excellent Eyesight Eagles do have "eagle eyes." They can see 4 to 5 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.