Bald Eagle

 

 

Common Name: Bald Eagle

Class:  Aves

Order: Accipitriformes

Family: Accipitridae

Genus: Haliaeetus

Species: Haliaeetus leucocephalus

Photo: Ivan Andrijevic

 

TAXONOMY

 

The Bald Eagle is a member of the Accipitridae Family, under the Order Accipitriformes, meaning that it is a diurnal bird of prey.  Its name is derived from “Haliaeetus,” meaning “sea eagle,” and “leucocephalus,” meaning “white head.”  The common name, “Bald Eagle” comes from the English word “piebald,” which usually refers to a black and white pattern referring to the Bald Eagle’s white head and tail. Immature Eagles do not reach adult coloration until around five years old. Until that time they are a molted brown color.

 

      
Photos: Ivan Andrijevic & M. Noonan

Bald Eagles have a body length of around 27-40 in (68 to 100 cm).  Females are 25% larger, showing a clear example of sexual dimorphism.  The female wingspan is 7 ft (2.1 m), while the male wingspan is 6 ft 6 in (2 m).  The average weight of a female is 12.9 lbs (5.8 kg) and the male weighs 9 lbs (4.1 kg). In the wild Bald Eagles typically live 20 to 30 years, but they have been known to live up to 50 years.  Bald Eagles that live in captivity typically live up to 60 years.

 

HABITAT/DIET

Bald Eagles are usually found in habitats that provide plenty of warm-water fishes.  These areas include seacoasts, rivers, and large lakes. They seem to prefer water bodies with a circumference of at least 7 mi (11 km). 

Their diet consists mostly of fish, but they also eat other birds such as grebes, ducks, geese and mammals such as rabbits, raccoons, muskrats, and even deer fawn.  Bald Eagles also rely on carrion and will often live off of carcasses throughout the winter.

 

      

Photos: M. Noonan

 

BEHAVIOR

 

Bald Eagles display the same behaviors as other birds including preening and brooding.  They are not known to be aggressive birds, but when a confrontation occurs, it is usually fatal.  Bald Eagles will also steal prey from other birds of prey, such as Ospreys, who often share habitats with Bald Eagles.  Many believe that Bald Eagles mate for life, however, if one member dies, they will be replaced. 

For courtship, Bald Eagles display a “cartwheel” where they lock talons and freefall until right before hitting the ground.  Bald Eagles return to the same nest each year and these nests can reach 8 feet across, weigh a ton, and usually are found in trees.  However, if no trees can be found, they have been known to nest on the ground.  Each year, the eagles lay one to three eggs and both the male and female take turns brooding.  Incubation lasts 35 days and the fledglings are cared for for 8 to 14 weeks.

 

Photo: M. Noonan

WHERE TO FIND THEM

 

Although Bald Eagles were declared and Endangered Species in 1967, due to conservation and knowledge, their population has made a comeback and on June 28, 2007, the Department of Interior took the Bald Eagle off of the Endangered Species list.  They are still protected by the Migratory Bird Treaty Act and Bald and Golden Eagle Protection Act.

Bald Eagles are found year found in New York State, where they once were almost extirpated. Their resurgence is thanks to the Endangered Species Act and the NYS Department of Environmental Conservation’s hacking program, which was carried out in the 1980’s at Iroquois NWR. There are four active Bald Eagle nests in the Iroquois Wetlands Complex including one each at Oak Orchard State Wildlife Management Area and Tonawanda State Wildlife Management Area and two at Iroquois NWR. One of the latter nests is located at the back at Cayuga Pool and is visible from the overlook parking lot.

 

Photo: M. Noonan

 

Birds of Western New York is brought to you by the Institute for the Study of Human-Animal Relations at Canisius College in Buffalo, NY.