Bald Eagle, Haliaeetus leucocephalus

Bald Eagle, Haliaeetus leucocephalus. Bird photographed in coastal Homer, Alaska, March 2024. Photograph courtesy of Rachel Garat, Homer.

Bald Eagle, Haliaeetus leucocephalus. Photographs of birds in captivity in the Wild Wild West.

Background and Identification

The Bald Eagle, Haliaeetus leucocephalus, is a member of the Accipitridae Family of Hawks, Eagles, and Kites. A majestic bird of prey, the Bald Eagle is the national bird and symbol of the United States. It was selected as the species to stand as the national emblem in 1782 by the United States Congress. In both the past and the present, its feathers and body parts appear regularly in prehistoric settlements of Native American peoples. The Bald Eagle represents freedom and democracy in the United States. As it is said, the United States is the “land of the free, home of the brave”. Despite its name, the Bald Eagle is not bald; “bald” comes from an old English word “piebald”, which means white-headed. Bald Eagles mate for life, and are known for building large nests, called eyries, in tall trees or on cliffs, often reused and added to year after year.  In Mexico, they are known as Águila Calva.

Bald Eagles are one of the largest birds in North America, with a total length of 71 cm (2 feet 4 inches) to 96 cm (3 feet 2 inches), a wingspan of 1.68 m (5 feet 6 inches) to 2.44 m (8 feet 0 inches), and a body mass of 3.0 kg (1 lb 6 oz) to 6.3 kg (2 lbs 14 oz). The largest individuals are found in Alaska and Canada, and the smallest in the southeastern and southwestern United States. More information on the geographical range and migration of the Bald Eagle is present in the next section, “Habitat and Geographical Range”. Female individuals are usually about 25% larger than males. This raptor is easily recognized in adulthood by its striking white head and tail feathers contrasted with a dark brown body and wings. Mature adults typically have yellow eyes, beaks, and talons. Juvenile Bald Eagles have mottled brown and white plumage and do not acquire adult coloration and plumage until they are about five years old. More specifically, 25% of birds acquire adult coloration by four years six months of age, and most individuals acquire adult coloration by five years six months of age. Juveniles have mottled brown and white plumage, with no distinct color differences between their head and body. The mottled colors include dark brown, light brown, beige, and off-white.

Habitat and Geographical Range

Bald Eagles are native to North America and can be found across a wide range of habitats, from rugged coastlines to forested areas. They are most commonly associated with large bodies of open water, including rivers, lakes, and coastal estuaries, where they can find abundant food sources such as fish. Fish are Bald Eagles’ primary diet. Occasionally, Bald Eagles eat limited amounts of birds, mammals, and reptiles.

Bald eagles are native to North America and have a range that includes most of Canada and Alaska, all of the contiguous United States, and northern Mexico. They are known to winter along the coastal regions of the Atlantic Slope in Tamaulipas and within the Pacific Slope of Baja California and Sonora and several river systems of Chihuahua at elevations up to 2,000 m (6,600 feet).

Common Misidentifications

Bald Eagles are sometimes mistaken for other large birds of prey, particularly when they are juveniles. The most common misidentification is the Golden Eagle, Aquila chrysaetos. These eagles have a similar size and shape but lack the white head and tail of mature adult Bald Eagles. Golden Eagles are uniformly brown with a slight golden sheen on the back of their head and necks. Also mistaken for the Bald Eagle (juvenile) are the Osprey, Pandion haliaetus, and the Turkey Vulture, Catharhtes aura. Ospreys are smaller than Bald Eagles and have distinctive black eye stripes that extend to the sides of their heads, unlike the Bald Eagle’s all-white head. Turkey Vultures appear similar to Bald Eagles when soaring, but they have a distinctive V-shaped wing posture in flight and red, featherless heads.

Conservation Status

From a conservation perspective, the Bald Eagle is currently considered to be of Least Concern with stable, widely distributed populations. Once on the brink of extinction due to habitat destruction, illegal shooting, and the effects of DDT (a pesticide that weakens the eggshells of birds), the species was listed as endangered in the lower 48 states in the late 20th century. Conservation efforts, including legal protection under the Bald and Golden Eagle Protection Act and the banning of DDT, have led to a significant recovery. As a result, the Bald Eagle was removed from the U.S. federal list of endangered and threatened species in 2007.