Golden Eagle

Golden Eagle

Aquila chrysaetos

CLASSIFICATION

Class:	Aves
Order:	Falconiformes
Family:	Accipitridae
Genus:	Aquila
Species:	chrysaetos

SIZE

Length:	Male:	29-35 inches
	Female:	32-40 inches
Weight:	Male:	5-10 pounds
	Female:	6-14 pounds
Wingspan:	Male:	5-7 feet
	Female:	6-8 feet

APPEARANCE:

Plumage is dark brown with golden feathers at the back of the head and neck. Legs are feathered to the feet which are yellow. The beak is bluish-black with a yellow cere. Wings are broad, and the tail is rounded. Eyes are brown.

The immature is similar in color but with whitish areas at the base of the flight (primary) feathers that are noticeable in flight, and the tail of an immature bird is 2/3 white with a broad black band at the end. Each year as the bird molts, the white diminishes until at maturity (by about 5 years) it disappears completely. The eyes in the immature are also a darker brown.

Golden Eagles are sometimes mistaken for the immature Bald eagle at a distance. They can be distinguished by the feathered tarsi, slightly larger wingspan, and smaller beak.

RANGE/DISTRIBUTION:

Golden Eagles are found in Europe, Asia, North Africa, Arabia, and North America. The Golden Eagle is probably the most numerous eagle of its size in the world. In North America, they are more common west of the Mississippi River. They were nearly extinct in the eastern United States until a few years ago.

HABITAT/TERRITORY SIZE:

Habitat is sea level to 10,000 feet in rugged, rocky canyon country, open desert, and grassy plain.

The territory of a pair of Golden Eagles varies, depending on the available prey. In Scotland they required 11,000-18,000 acres. In California they need from 19-59 square miles with an average of 35. In forested country such as northeast North America, the range hunted by a particular pair may be as much as 200 square miles, but then only a small portion of the total range (10-40%) may have been open enough to hunt.

MIGRATION:

A partial migrant, the northern breeding birds migrate south in winter, while those of more temperate climates remain all year round.

DIET:

Diet consists of small mammals, birds, reptiles, jack rabbits, and carrion. It shows a strong preference for mammals. In various parts of its range the percentage of mammals in their diet varies from 70-98% by weight.

When game birds are abundant, they form a considerable portion of the diet. The Golden Eagle is credited with the ability to kill adult antelope and deer, but authentic accounts are very rare. The largest normal prey taken is a deer calf weighing perhaps 15 pounds. Golden Eagles have been accused of killing domestic sheep. There is no doubt that most of the lambs taken are already dead. Very rarely live lambs may be killed; but, on balance, the eagle is beneficial on account of the number of large rodents and potential predators, like young foxes, that it kills.

HUNTING METHOD:

Golden Eagles use their great soaring ability and incredible eyesight to locate their prey. After spotting their prey, they dive at speeds up to 120 mph and grab their prey with their large feet and talons. With feet and talon strength of 750 p.s.i., their prey is usually killed instantly. Most of the prey is taken on the ground, but occasionally large birds such as goose and crane or even diving ducks may be struck in the air.

BREEDING INFORMATION:

Maturity is reached at 4-5 years. In temperate areas, Golden Eagles take an interest in its nest site for most of the year, and nuptial display may be seen in almost any month. The most unusual display is a series of dives followed by upward swoops, with a few wing flaps at the top of each swoop, ten or a dozen at a time, rising and falling 50-100 feet. Most likely, the pair will be soaring, and the male will dive towards the female who turns on her back and presents her talons to his.

Nests are constructed on rocky cliffs or in tall trees. The same nests will be used year after year, adding to it each time. Nests on ledges of cliffs can be up to 8 feet in diameter and 3-4 feet thick. Those built in trees are usually deeper and more massive with the largest recorded nest being 17 feet deep and 4 feet across. The North American eagle’s eggs, laid in March, are dull white with brown blotches. They can lay 1-4 eggs, but the most common is 2. Eggs are laid at 3-4 day intervals. Incubation is 4-6 weeks, depending on location, and is done mostly by the female. The young hatch at intervals of several days, and in about 80% of cases where two young hatch, the elder kills the younger. In the first 14 days, the young are tended by both parents, but after 21 days they are left alone most of the day. Feathers first appear through the down at 21-25 days, and by 45-50 days, the young are feathered. From 50 days onward, they can feed on prey brought to the nest by their parents on their own. They make They make their first flight at 65-70 days, but may stay in the nest for more than 80 days.

BEHAVIOR:

Generally a silent bird, occasionally it utters a loud clear yelping call “weeeo-hyo-hyo-hyo”. Mewing cries “weee-o” in display. Otherwise a thin shrill “pleek” or “tsewk”. Soliciting young at the nest have clucking calls “tsyuck-tsyuck”, and in anger emit harsh high pitched chattering.

On the wing the Golden Eagle is a splendid flyer, and the grace of its flight is eclipsed among birds of its size only by the Verreaux’s Eagle. It will soar for hours without effort, usually sailing above a ridge on the breeze with partly folded wings, or rising in spirals far into the sky.