The Ecology of Bald Eagles in Arizona

Perhaps no bird spurs the imagination and admiration of the public like the bald eagle. The national bird of the United States, the bird has a massive wingspan of almost 80 inches and sports a pure white head with age. In 2011, the mighty birds remain protected under the federal Endangered Species Act; within the state 104 breeding adults reside, according to the Arizona Republic.

  1. Breeding Areas

    • Within the state of Arizona, 50 bald eagle breeding areas exist. The eagles usually locate their nest within one mile of a water source, such as a creek, lake or river, according to the Southwestern Bald Eagle Management Committee. The birds usually prefer to construct their nest on a rock crevice, outcropping or on rock pinnacles. They will also utilize a cottonwood tree. On rare occasions, the nests may occur in ponderosa pines, pinyon pines, willows and sycamores.

    Human Disturbance

    • Human activity within the state can disturb the bird's breeding site. The Arizona Department of Transportation states that low flying airplanes can seriously disrupt the nesting eagles. The plane's noise can cause the eagle to evacuate its nest hastily, which often results in broken eggs. Air flight advisories exist over bald eagle breeding locations within the state. If an aircraft pilot fails to obey the advisory, the pilot could face serious fines or prison time.

    Migration

    • In Arizona, breeding can occur from December to March, but most eagles breed in January and February. The eggs incubate for 35 days before hatching. Both male and female take care of the eggs and the hatchlings. The young eagles fledge at approximately 12 weeks. Approximately 45 days after the young eagle leaves its nest, it will migrate from Arizona to northern California, North Dakota, South Dakota, Oregon, Wyoming, Montana, Idaho, Washington or Canada. The young will return to Arizona from September and October. The young will often migrate annually, until three or four years old. Resident adults usually remain in the nesting regions. During the winter months, bald eagles will migrate from northern states into Arizona. According to Arizona Leisure, approximately 300 migrating bald eagles winter in Arizona each year.

    Survival in the State

    • Bald eagles consume a diet that consists primarily of fish. In Arizona, the eagle eats large quantities of largemouth bass, smallmouth bass, yellow bass, white bass, black crappie, Sonora suckers, desert suckers, flathead catfish and channel catfish. The Arizona bald eagle may also consume bluegill, tilapia, rainbow trout, green sunfish and roundtail chub. The bald eagle can thrive in Arizona if human disturbances are controlled and limited. A long-term resident of the state, eagle bones have been discovered along the Little Colorado River near Grand Falls that date from 700 to 1300 AD. The bird's long term residency within Arizona indicates that it has developed an ecological niche in the region.