How large of an animal will an eagle attack?

Although regional and seasonal differences in food habits exist, golden eagle prey consists mostly of small mammals such as jackrabbits, cottontails, prairie dogs, and ground squirrels. A variety of birds and reptiles also have been recorded as prey. Nesting pairs or concentrations of juvenile birds can be a major cause of predation on local game bird populations. Golden eagles also readily eat carrion.

Golden eagles sometimes attack large mammals; deer and pronghorns of all ages have been observed being attacked or killed by eagles. Records also exist of bighorn sheep, coyotes, bobcats, and foxes being killed. Occasionally, golden eagles kill calves, sheep, or goats. However, attacks on animals that weigh more than 30 to 40 pounds (14 to 18 kg) are uncommon. Where golden eagles prey on domestic animals, they usually take lambs and kids, but some become persistent predators of domestic livestock as large as 500 pounds (227 kg).

Bald eagles rely heavily on fish and carrion where available. They readily adapt, however, to preying on waterfowl, other birds, rabbits, and other small mammals. They also occasionally kill adult deer, pronghorns, and calves. At times, some may prey repeatedly on domestic sheep and goats, primarily young lambs and kids.

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