Bald eagle

Taxonomy and Description

The bald eagle belongs to the genus Haliaeetus, or sea eagles, and its scientific name, Haliaeetus leucocephalus, derives from Greek and Latin roots meaning 'white-headed sea eagle'. The common name 'bald' references an older meaning of the word denoting a white patch, not a lack of feathers. The species was first formally described by Carl Linnaeus in the 18th century. It forms a species pair with the white-tailed eagle of Eurasia, sharing a similar ecological niche. Two subspecies have been historically recognized, with the northern subspecies (H. l. washingtoniensis) generally larger than the southern nominate subspecies (H. l. leucocephalus), a pattern consistent with Bergmann's rule where animals are larger in colder climates.

The adult bald eagle's plumage is a uniform dark brown with a stark white head and tail, a colouration attained only at sexual maturity around four or five years of age. The sexes are identical in colour, but females are about 25 percent larger than males. The species exhibits significant size variation across its range, with the largest individuals found in Alaska. The bird's beak is large, hooked, and yellow, as are its powerful legs and feet, which are equipped with sharp talons for grasping prey.

Immature bald eagles are mostly dark brown mottled with white streaks and blotches, a plumage that can cause confusion with other large raptors. They can be distinguished from golden eagles by their larger heads and beaks, straighter wing edges held flat in flight, and feathers that do not completely cover their legs. The bald eagle's call is often considered surprisingly weak for its size, consisting of a series of chirping or squeaking whistles. The more dramatic 'screaming' call commonly associated with eagles in media is typically the call of a red-tailed hawk.

Range and Habitat in Canada

The bald eagle's natural range spans most of North America, including all of Canada, all of the contiguous United States, and northern Mexico. In Canada, the species is widely distributed, with significant breeding populations along the coast of British Columbia and in the forested regions of Alberta, Saskatchewan, Manitoba, and Ontario. Northern populations are often migratory, moving southward or to coastal areas when inland waters freeze, while southern populations tend to be resident year round. A major winter congregation site is in Squamish, British Columbia, where one to two thousand eagles gather from November to February to feed on spawning salmon in the Squamish and Cheakamus Rivers.

Bald eagles are highly associated with aquatic environments. For breeding, they require large bodies of open water, such as coastlines, major rivers, and large lakes, that provide an abundant supply of fish. They nest in old growth or mature stands of coniferous or hardwood trees that offer stability, good visibility, and proximity to water. Nests, known as aeries, are typically built high in the canopy, from 16 to 38 metres above the ground, though they can be lower in mangroves or other trees standing in water. The nests are the largest of any North American bird and can grow to immense sizes over years of use, with the largest on record measuring 6.1 metres deep and 2.9 metres wide.

While generally sensitive to human disturbance during nesting, bald eagles have shown adaptability. They have established nests in major urban areas, including a notable instance in Toronto in March 2024, which was the first recorded nesting pair in that city. Suitable wintering habitat can be more varied, including upland areas, open prairies, and tundra, especially in regions where unfrozen water is not accessible. In these settings, they often rely more on carrion and terrestrial mammals such as rabbits and prairie dogs.

Diet and Hunting Behaviour

The bald eagle is an opportunistic carnivore with a highly varied diet, though fish form the majority of its prey across its range. Studies indicate that fish comprise about 56 percent of the diet of nesting eagles, with birds making up 28 percent, mammals 14 percent, and other prey 2 percent. The species is known to prey upon or scavenge from more than 400 different species. To hunt fish, an eagle typically swoops low over the water and snatches the fish from the surface with its talons, rarely diving fully into the water like an osprey. It will then carry the fish to a perch, holding it with one foot while tearing flesh with the other.

Bald eagles are also skilled at pirating food from other birds, particularly ospreys. They will harass an osprey carrying a fish until the smaller raptor drops its catch, which the eagle then retrieves in mid air. They hunt bird prey, including waterfowl up to the size of Canada geese, sometimes attacking them in flight. Mammalian prey includes rabbits, squirrels, prairie dogs, and muskrats. Carrion is an important food source, especially in winter, and eagles will readily feed on dead fish and animals. Their powerful grip, estimated to be ten times stronger than a human's, is facilitated by spicules on their toes that help them grasp slippery prey.

The bald eagle's foraging strategy often involves perching for long periods in a tree with a good vantage point over open water, waiting to spot prey. It is a powerful flier, capable of reaching speeds of 56 to 70 km/h when gliding and flapping. Its dive speed is between 120 and 160 km/h, though it seldom dives vertically. Despite being morphologically less well adapted to faster flight than golden eagles, the bald eagle is considered surprisingly maneuverable in flight. Bald eagles have been recorded catching up to and then swooping under geese in flight, turning over and thrusting their talons into the other bird's breast.

Life Cycle and Reproduction

Bald eagles are generally monogamous and mate for life, reinforcing their pair bond through spectacular aerial displays that may involve locking talons and cartwheeling toward the ground. This dramatic behaviour, however, is more often an aggressive territorial dispute between rivals than a courtship ritual. Breeding territories are established near water and can vary greatly in size depending on geographic location and food availability. Courtship and mating occur on secure perches and are preceded by behaviours like tail pumping and wing flapping.

The pair builds a massive nest of sticks, lined with softer materials like grass and moss, in a large tree. The same nest is often reused and enlarged year after year. The female typically lays one to three eggs, which are incubated by both parents for about 35 days. The young eagles, called eaglets, are altricial and remain in the nest for 10 to 13 weeks, being fed by both parents. After fledging, the juveniles remain dependent on their parents for several more weeks as they learn to hunt.

Young bald eagles reach sexual maturity at four to five years of age, which is also when they finally moult into the adult plumage of a white head and tail. Prior to this, they undergo a series of mottled brown and white plumages. Juvenile eagles often disperse widely from their natal territory, with post breeding dispersal particularly noted in birds from Florida moving north in the summer. Bald eagles can be long lived, with lifespans in the wild often exceeding 20 years.

Conservation History and Status

The bald eagle's population in North America suffered a catastrophic decline through the mid 20th century. By 1963, only 417 known nesting pairs remained in the contiguous United States. The primary causes were habitat loss, deliberate killing, and, most significantly, contamination of aquatic ecosystems by the pesticide DDT. DDT caused eggshell thinning, leading to widespread reproductive failure as eggs broke during incubation. The species was listed as endangered under the U.S. Endangered Species Act in many states.

A remarkable conservation recovery began with key legislative actions. The Bald and Golden Eagle Protection Act and the Migratory Bird Treaty Act provided strong legal protections against killing, disturbance, and trade. Intensive management, including habitat protection and public education, supported the species' rebound. The population responded dramatically, leading to its reclassification from 'endangered' to 'threatened' in 1995 and its complete removal from the U.S. Endangered Species List in 2007.

As of a 2018 2019 survey, the contiguous U.S. population was estimated at approximately 316,700 individuals, demonstrating one of the greatest wildlife conservation successes in North American history. The species is classified as Least Concern on the IUCN Red List. In Canada, populations are healthy and widespread. However, the eagle remains federally protected in the United States under the Bald and Golden Eagle Protection Act, and some states, like California, still list it as endangered. Ongoing threats include lead poisoning from ingested ammunition fragments, vehicle collisions, electrocution on power lines, illegal shooting, and habitat disturbance.

Cultural Significance and Viewing

The bald eagle is the national bird and symbol of the United States, appearing on its seal and currency. In Canada, it is a widely recognized symbol of wilderness and strength, and its dramatic recovery from the brink of extinction has made it a powerful emblem for the conservation movement. This recovery demonstrates the positive impact of science based policy and public action, and institutions like the National Eagle Center in the United States use non releasable eagles to educate the public about the species and its conservation journey. For Canadians interested in viewing bald eagles, the winter congregation in Squamish, British Columbia, is one of the most spectacular sights, with many rivers and coastal areas across the country providing excellent viewing opportunities, especially during salmon runs.

In recent years, eagles have increasingly been observed in urban areas, such as the nesting pair documented in Toronto in 2024. When observing eagles, it is crucial to avoid disturbing them, particularly during the sensitive nesting season from winter through summer. Using binoculars or a spotting scope from a respectful distance ensures the birds are not stressed or driven from their nests. The species' presence across Canada, from the Pacific coast to the Great Lakes and the boreal forest, makes it an accessible part of the natural heritage for many Canadians. Its continued success depends on ongoing stewardship, including responsible fishing and hunting practices to reduce lead contamination, protection of waterfront habitats, and public awareness of the laws that protect this majestic raptor.

Questions about Bald eagle

Are bald eagles still endangered in 2026?

No, bald eagles are no longer listed as endangered or threatened under the U.S. federal Endangered Species Act. They were removed from the list in 2007 following a major population recovery. However, they remain protected under the Bald and Golden Eagle Protection Act and the Migratory Bird Treaty Act. Some individual states, such as California, still classify them as endangered, and they are considered a species of special concern in others like Massachusetts.

What do bald eagles eat?

Bald eagles are opportunistic carnivores with fish making up the majority of their diet, especially near nesting sites. They also prey on birds, including waterfowl like ducks and geese, and mammals such as rabbits, squirrels, and muskrats. They are adept at scavenging carrion and are notorious for stealing fish from other birds, particularly ospreys, by harassing them in flight until they drop their catch. Their diet includes over 400 different species across their range.

Where can I see bald eagles in Canada?

The majority of bald eagles in Canada are found along the British Columbia coast. Large populations are also found in the forests of Alberta, Saskatchewan, Manitoba and Ontario. From November until February, one to two thousand birds winter in Squamish, British Columbia, attracted by salmon spawning in the area. In March 2024, bald eagles were found nesting in Toronto for the first time.

Why are some bald eagles not white-headed?

Bald eagles do not develop their white head and tail feathers until they reach sexual maturity at four to five years of age. Juvenile eagles are mostly dark brown mottled with white streaks and blotches. This immature plumage provides camouflage and changes gradually over several annual moults. The full adult plumage is a sign the bird is ready to breed.

How big is a bald eagle's nest?

Bald eagles build the largest nests of any North American bird. These massive structures, called aeries, are constructed from sticks and lined with softer materials. They are reused and added to each year, and can grow to enormous sizes. The largest recorded nest was found in Florida in 1963 and measured 6.1 metres (20 feet) deep and 2.9 metres (9.5 feet) wide. A typical nest is about 1 to 2.5 metres wide and can weigh up to a metric ton.

Sources: Wikipedia and current public reporting, checked by the Your Space Hamilton desk. Last updated 2026-10-18.