- Common Name:
- Bald eagle
- Scientific Name:
- Haliaeetus leucocephalus
- Group Name:
- Average Life Span In The Wild:
- 20 to 30 years
- Body: 28 to 38 inches; Wingspan: 80 inches
- 6 to 14 pounds
- IUCN Red List Status:
- Least concern
- Current Population Trend:
What is a bald eagle?
The bald eagle is a large, powerful bird that has been the national symbol of the United States since 1782, when it was first placed with outspread wings on the country’s Great Seal as a sign of strength. Bald eagles don’t actually have bare heads. Their name is derived from the old English word “Balde,” which means white—a nod to the snowy-white feathers that cover their heads and tails. Most of these majestic, brown-bodied creatures live in Alaska and Canada, but they also inhabit Mexico and every U.S. state except for Hawaii.
Despite their national fame, bald eagles were almost wiped out in the U.S. in the mid-1900s due to decades of sport hunting and habitat destruction. DDT, a pesticide that became popular after World War II, also wreaked havoc on bald eagles that ate contaminated fish, weakening their eggshells so much they’d crack during incubation. In 1972, the U.S. banned DDT use and began intensive population management strategies that led to eagle recovery in the wild and their eventual removal from the Endangered Species Act list in 2007. (Most U.S. eagles suffer from lead poisoning, study suggests.)
Today bald eagle numbers continue to soar despite threats like illegal hunting and electrocution from power lines. A 2019 survey found that the population in the lower 48 states quadrupled since 2009.
Habitat and diet
While bald eagles occasionally live in arid areas, most reside in woods by rivers, lakes, and other bodies of water rich with fish, their main food source. Their diets also include birds, turtles, and small mammals such as squirrels and rabbits.
To conserve energy, these opportunistic creatures sometimes scavenge on dead animals or steal prey from birds and other animals despite being gifted hunters themselves. Like hawks, falcons, and other predatory birds, bald eagles are considered raptors and have a number of adaptations that make them built for the chase: razor-like talons for puncturing and carrying up to eight-pound victims, a large wingspan for conserving energy by soaring, and a dense coating of light-detecting cells on their retinas that helps them spot prey from up to a mile away. (Winter is prime time for watching bald eagles—here's where to spot them.)
Once an eagle has secured a meal, it uses the sharp edges of its curved beak to slice through flesh or scales.
Breeding and family life
Most bald eagles reach sexual maturity at age four or five and breed in early spring. Males and females bond by performing dance-like air displays like the “cartwheel courtship flight,” in which a pair flies high into the sky, locks talons, does a cartwheel-like spin downward, and then breaks off right before hitting the ground.
Those teamwork skills come in handy when it’s time to build nests, stick structures lined with grass and other materials that can take several months to construct. Most couples build them at the tops of tall trees strong enough to support the enormous structure—the largest nest of any bird in North America at about six feet wide and four feet deep. Pairs living in treeless areas build nests on cliffs or, on rare occasions, the ground. (See photographs depicting the everyday lives of this national symbol.)
Most bald eagle couples return to these sturdy homes each year to mate and care for a new pair of eaglets. Both parents play an active role in rearing; they deliver prey, place torn-up food into eaglet beaks, and fiercely guard little ones from predators like raccoons and ravens. The all-brown juveniles (which won’t have the distinctive white markings of their parents until age five) begin to fly at about 10 to 12 weeks and permanently leave the nest a month later.
Untethered to a breeding site, young eagles tend to roam far from their nests in directions that appear random. Adult birds are more intentional, migrating only as far as necessary to find sustenance. When lakes and rivers freeze, for example, Northern bald eagles fly to the coast or south to open water.
Although these highly territorial birds typically travel alone, they often roost together during non-breeding times in groups ranging from several birds to hundreds of them. Scientists think they congregate to socialize or pick up on information about the location and availability of prey. To communicate, they emit a variety of whiny, high-pitched vocalizations that may sound surprising coming from such brawny bodies.
Did you know?
— Audubon Center for Birds of Prey
Bald eagles swim by moving their wings in a rowing motion that looks similar to the butterfly stroke.
Bald eagles store excess food in a crop, a muscular pouch below their throat that looks like a bulge from the outside.
— American Eagle Foundation
In 1784, Benjamin Franklin wrote a letter to his daughter saying the bald eagle was a poor choice for the U.S. national symbol because of its thieving tendencies.
— The Franklin Institute