Bald Eagle
COMMON NAME: Bald Eagle
SCIENTIFIC NAME: Haliaeetus leucocephalus
TYPE: Birds
DIET: Carnivore
AVERAGE LIFE SPAN IN THE WILD: Up to 28 years
SIZE: Body: 34 to 43 inches; wingspan: 6 to 8 feet
WEIGHT: 6.5 to 14 pounds
SIZE RELATIVE TO A 6-FT MAN:
The bald eagle, with its snowy-feathered (not bald) head and white tail, is the proud national bird symbol of the United States—yet the bird was nearly wiped out there. For many decades, bald eagles were hunted for sport and for the "protection" of fishing grounds. Pesticides like DDT also wreaked havoc on eagles and other birds. These chemicals collect in fish, which make up most of the eagle's diet. They weaken the bird's eggshells and severely limited their ability to reproduce. Since DDT use was heavily restricted in 1972, eagle numbers have rebounded significantly and have been aided by reintroduction programs. The result is a wildlife success story—the U.S. Fish and Wildlife Service has upgraded the birds from endangered to least concern.
Habitat and Diet
Though their numbers have grown in much of their range, bald eagles remain most abundant in Alaska and Canada. These powerful birds of prey use their talons to fish, but they get many of their meals by scavenging carrion or stealing the kills of other animals. (Such thievery famously prompted Ben Franklin to argue against the bird's nomination as the United State's national symbol.) They live near water and favor coasts and lakes where fish are plentiful, though they will also snare and eat small mammals.
Breeding
Bald eagles are believed to mate for life. A pair constructs an enormous stick nest—one of the bird-world's biggest—high above the ground and tends to a pair of eggs each year. Immature eagles are dark, and until they are about five years old, they lack the distinctive white markings that make their parents so easy to identify. Young eagles roam great distances. Florida birds have been spotted in Michigan, and California eagles have traveled all the way to Alas
Two eaglets recently hatched at the U.S. National Arboretum in Washington, D.C. from a nesting pair named “Mr. President” and “First Lady.” The bald eagle chicks have been enjoying their first meals of fish, which the parents have been taking turns collecting.
Clearly recognized by its white head, brown body, and hooked yellow beak, the bald eagle has been the national emblem of the United States of America since 1782.
Yet starting in the 1950s, this symbol of American patriotism began to dramatically decline in numbers due to the use of the chemical DDT. After rigorous conservation efforts by the United States government, the bald eagle successfully rejuvenated its population and can comfortably continue its role as the national bird of the US.
With a 2 m (7 ft.) wing span, a weight of 3-7 kg (7-15 lb.), and an overall size of 71-96 cm (28-38 in.), the bald eagle is one of the largest raptors in the world.
Living near a constant source of water, bald eagles feast on fish, ducks, snakes and turtles. They will also eat rabbits, muskrats, and dead animals. Utilizing their acute sense of sight and powerful talons, bald eagles attack their prey by swooping down on them at an angle.
They can reach speeds of up to 160 km/hr (100 mph) when diving. Once they capture their prey, they use their hooked beak to pull flesh out before eating it.
Bald eagles can reach great heights when flying. Using thermal convention currents, they can climb to up to 3000 m (10,000 ft.) in the air. They can soar for hours using these currents. When cruising, they can fly about 65 km/hr (40 mph). In addition, if their water source freezes, bald eagles may use thermal convention currents to migrate in the winter.
Family Life
At around 4-5 years old, bald eagles will choose a mating partner through a courtship procedure. The courtship includes numerous calls and aerial displays. Once coupled, the two birds will mate for life. Only in the case where one eagle dies or disappears will the other one find a new mate.
Preferring to make their homes in large trees near bodies of water (both fresh and salt), bald eagles build enormous nests, called eyries, out of sticks. Generally, their eyries are at least half a meter (2 ft.) deep and 1.5 m (5 ft.) across but can be bigger. These substantial nests have been known to weigh up to 900 kg (1 ton).
A mating pair produces up to three eggs a year, though it is not likely that all three will survive. Both parents take turns incubating the eggs. While one is incubating, the other searches for food or more nesting materials.
After a little over a month of incubation, the eggs hatch. Bald eagles are not born with their distinctive brown and white look. When baby eaglets hatch, their entire bodies are covered with light gray feathers. Around 3 weeks, their plumage takes on a brown coloration. Finally, at 4-5 years old, they acquire the distinctive brown and white color pattern.
Conservation Status
In 2007, the bald eagle was removed from endangered and threatened species list kept by the United States Fish and Wildlife Service. In addition, IUCN’s Red List currently considers the bald eagle as a species of least concern of extinction. Their successful recovery is due to years concerted conservation efforts along with the ban on the pesticide DDT in 1972.
While bald eagles have few natural enemies and are no longer considered endangered, threats still exist to the bald eagle, including habitat loss. As people move to the shores, they are cutting down trees and forcing eagles to make their homes elsewhere. Illegal hunting is another threat.
What You Can Do to Help
A good way to help bald eagles is to educate the public about the birds’ habitat requirements. Encourage shore property owners to limit the clearing of trees near the water, and advocate for less development in eagle habitat. You can also donate to the American Eagle Foundation.
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