Bald Eagle Facts

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The one eagle that is native to only North America is the bald eagle. It is found mainly in Canada and Alaska, but also ranges in smaller numbers across the lower 48 states of the United States, and into Mexico. Hawaii does not have any eagles.

The bald eagle is a national symbol for the United States.

 
Scientific Name Order: Falconiformes Family: Accipitridae Genus/Species: Haliaeetus leucocephalus

With its snow white head, brown body, and large wing span, it can be recognized even from a distance. The vision of a majestic eagle soaring on the thermal winds high in the sky is iconic, a symbol recognized by most everyone in the United States and Canada.

Bald eagles can fly to an altitude of  up to 10,000 feet. It is the highest flying bird in North America, and as such is recognized by all native american tribes in the US as a sacred bird, capable of carrying prayers to the Gods. This bird of prey rarely beats his wings once it gains altitude. Instead this raptor holds his wings completely flat, conserving energy by making use of wind currents to glide through the sky. He uses the tail feathers as a rudder, and curves the tips of his wings downward to help make turns.

Physical Characteristics

The familiar hooked bill, legs and feet are yellow. Only the tops of the bald eagle’s legs have feathers. The other eagle native to North America, the golden eagle, has feathers all the way to its feet. Adult bald eagles are a dark brown (nearly black) bird with a white head, neck, and white tail feathers. Females are larger that the males, weighing about 14 pounds with a wing span up to eight feet across. Males weigh about 6 to 10 pounds and have a wing span of about six feet. Body length varies from about three to three and a half feet. Only the California Condor is larger. Newly hatched, eaglets are covered with soft, grayish-white down. Juvenile birds are a mottled brown with white blotches. Immature bald eagles don’t develop their distinctive white head and tail until they are between 4 and 5 years old, and there are different color phases in the tail feathers before they reach their full adult coloring. Bald eagles make a high-pitched squealing sound that is often described as screaming or a screech.

Bald Eagle Facts for Kids

The bald eagle’s scientific name means “white-headed sea-eagle.” Another name for the bald eagle is the sea eagle, and sub-species include the Southern Bald Eagle (Haliaeetus leucocephalus leucocephalus) and the Northern Bald Eagle (Haliaeetus leucocephalus alascanus). The northern bald eagle is significantly larger than the southern bald eagle. While the Bald Eagle only lives in North America, its closest relatives live in other parts of the world. These include the African fish-eagle (Haliaeetus vocifer) of sub-Saharan Africa and the white-tailed sea-eagle (Haliaeetus albicilla) of Eurasia. The brood of chicks in the nest of a raptor are called an eyrie. An individual eagle baby is called an eaglet. An eaglet that is about ready to fly is called a fledgling. A juvenile has flown the nest but is under one year old. Immature eagles are over one year old, but not yet adults. Adulthood is reached at about 5 years old. Several eagles soaring in a thermal together is called a kettle of eagles. The skeleton of a full grown bald eagle only weighs about half a pound because the bones are hollow. Mature bald eagles have approximately 7,000 feathers. The beak, talons, and feathers are made of keratin, like your fingernails.

Diet of the Bald Eagle

The hooked beak is designed for tearing flesh, and the feet have powerful talons up to two inches long, used to grasp its pray and pluck it from water or land. A flying bald eagle averages speeds of 30 m.p.h., and diving onto its prey it can reach speeds of up to 100 miles per hour. Bald Eagle diets consist mainly of fish, carrion, smaller birds and rodents such as mice, rabbits, and prairie dogs. They also eat occasional snakes and other small reptiles and amphibians. Eagles are also known to prey on large birds, and even the occasional larger animals, such as muskrats, or even a deer fawn on rare occasions. They also steal food from other birds, such as the osprey. The eagle is one of the few birds who have a beak strong enough to crush turtle shells. Eagles have eyesight that allows them to see forward and to the sides at the same time. They have keen eyesight, four times better than humans,  and can spot movement on the ground from a mile away. They can spot fish below the water’s surface from several hundred feet away.  An eagle flying at an altitude of 1000 feet over open country could potentially spot prey over an area of almost three square miles.

Population of Bald Eagles

In the 1700s, it is estimated there were between 300,000 to 500,000 bald eagles in the U.S. By the 1800s, this number had dropped to about 100,000, primarily due to shooting by farmers and ranchers who believed they preyed on farm animals such as chickens, piglets, and lambs. They also believed they competed with fishermen for the salmon. In 1940, Congress passed the Bald Eagle Protection Act, which prohibited killing, selling, or possessing the species. A 1962 amendment added the golden eagle, and strengthened penalties. At this time, the law became known as the Bald and Golden Eagle Protection Act. By 1963,  their numbers had plummeted to only 487 nesting pairs in the lower 48 states, primarily due to over hunting, destruction of their habitat, and a pesticide called DDT, which was used in the raising of crops and to spray mosquitos, which got into the food chain and was stored in the fat and reproductive organs of birds. This weakened the shells of some birds, nearly causing the extinction of eagles in the US. In 1967-1970, eagles were declared an endangered species in 43 states, and became protected in all of the US in 1976. The eagle was the first species to be declared an endangered species, and they were the main reason the Endanged Species Act of 1973 was passed. In 2007 they were removed from the Federal List of Endangered and Threatened Species. However, they still remain protected from hunting. Since then, Bald eagle numbers have rebounded to 9,789 nesting pairs in the US according to recent population estimates in 2015. There are a total of about 70,000 bald eagles in the whole of North America.

Eagle Habitat

About half of North America’s bald eagles live in Alaska. British Columbia and the US northwest coast also have large eagle populations. They flourish in these areas in part because of the salmon migrations to spawn. Dead or dying fish are an important food source for all sea eagles. Bald eagles live near bodies of water in Canada and Alaska, and in scattered locations all over the lower 48 states and northwestern Mexico. There are no eagles in Hawaii. They are nearly always found near water, along rivers, lakes, or the sea coast and coastal marshes, reservoirs, and large lakes.

Reproduction of bald eagles

Southern bald eagles usually mate for life, but if one of them dies, the survivor will take a new mate. In the South eagles usually remain near where they were born for their whole lives. Northern bald eagles usually migrate long distances for the winter and return to the area where they were born in the spring. It is not known whether mated pairs stay together during this migration or form new bonds when they return. Southern birds may begin courtship and nesting activity in the late fall or early winter, from late September to early April, while it is more common for northern birds to court and nest in the early spring, usually from March to May. Florida eagles may nest any time of the year, but usually from November to January. During the breeding season, both the male and female work together to build a nest of sturdy sticks, usually located at the top of a tall tree. In areas where trees are scarce, they may nest on cliff ledges or even on the ground in some Alaskan areas. With more and more destruction of suitable habitats, some urban eagles will build their nests on top of telephone or power line poles. The shape of the eagle nest or aerie is determined mainly by the branch point where it’s built. Sticks placed in tree forks result in cylindrical or conical shaped nests. Disk shaped nests are built on the ground or a tree branch which is nearly level. Bowl shaped nests occur where the tree trunk branches off into smaller upright branches. Bald eagles usually return to the same nest year after year, repairing and adding to it each year. Eventually the nests can reach up to 8 to 10 feet in diameter and weigh anywhere from a half ton up to a ton. Each year, after the stick platform is reinforced, the nest cavity is lined with fresh twigs, grasses and other soft materials for the chicks. Young eagles will usually find a mate and build their nests within 100 miles of where they were born. If a nest is abandoned, a new pair of young eagles will sometimes take over an existing nest instead of starting from scratch. Breeding occurs on branches or other secure perches and is preceded by tail pumping and wing flapping displays by the male. Other interesting behaviors include “talon clasping” or a “cartwheel display”, where two eagles clasp each other’s talons in mid air and spin down, letting go only when they’ve almost reached the ground. This is may be done during a courtship ritual as well as a territorial battle. The female lays her first egg 5-10 days after mating. Each subsequent egg is laid a few days after the last one. Clutch sizes are 1-2 eggs, and rarely 3 eggs are laid. The eggs will hatch in the order they were laid. If food supply is scarce the first born chick may kill the others, especially if it is a female, since they are larger than males, and grow rapidly. From hatching to fledging takes about 4 months. However, the parents will still offer an occasional meal to the juveniles throughout the first winter. The eggs are incubated for about 35 days by both sexes, although the mother takes over most of the care of the eaglets after the eggs hatch while the male hunts and supplies them with food. But occasionally, the male will stay with the nest while the female goes out to hunt. The young eaglets are born bald, nearly blind, and unable to stand. They grow rapidly, adding one pound to their body weight every four or five days. By 3 weeks of age, they are a foot tall and their feet and beaks are nearly adult sized. At this age, the eaglets are covered in their secondary coat of gray down. In another two weeks or so, black juvenile feathers will begin to grow, which are necessary for flight. They will take their first flight about  10 to 13 weeks after hatching, but will return to the nest periodically until they are about 20 weeks old. After that, the parents will ignore them except to help them out with an occasional meal while they are developing their hunting skills. After the first winter, they are generally completely on their own. Bald eagles that make it past their first year usually live 15 to 25 years in the wild and up to 48 years in zoos. About 30% to 40% of fledglings die in their first year due to accidents, diseases, exposure to the elements, starvation, or interference from humans. Human disturbance can have an impact on nesting bald eagles, and if you get too close, they may abandon the nest.