Golden eagles are more likely to prey on livestock than bald eagles are. Both species readily feed on livestock carrion and carcasses left by foxes and coyotes, although some individuals prefer live prey to carrion. So do not assume that an eagle feeding on a carcass has necessarily been responsible for killing that animal. Eagles are efficient predators and can cause severe losses of young livestock, particularly where concentrations of eagles exist. Generally, they prey on young animals, primarily lambs and kids, although they are capable of killing adults. Eagles also take young deer and pronghorns, as well as some adults.
Eagles have three front toes opposing the hind toe, or hallux, on each foot. The front talons normally leave wounds 1 to 3 inches (2.5 to 7.5 cm) apart, with the wound from the hallux 4 to 6 inches (10 to 15 cm) from the wound made by the middle front talon. On animals the size of small lambs and kids, fewer than four talon wounds may be found, one made by the hallux and one or two by the opposing talons. Talon punctures typically are deeper than those caused by canine teeth and somewhat triangular or oblong. Crushing between the wounds usually is not found, although compression fractures of the skulls of small animals may occur from an eagle’s grip. Bruises from their grip are relatively common.
Eagles seize small lambs and kids anywhere on the head, neck, or body, frequently grasping from the front or side. They usually kill adult animals, or lambs and kids weighing 25 pounds (11 kg) or more, by multiple talon stabs into the upper ribs and back. Their feet and talons are well adapted to closing around the backbone, with the talons puncturing large internal arteries, frequently the aorta in front of the kidneys. The major cause of death is shock produced by massive internal hemorrhage from punctured arteries or collapse of the lungs when the rib cage is punctured. Eagles also may simply seize young lambs, kids, or fawns and begin feeding, causing the prey to die from shock and loss of blood as it is eviscerated.
Eagles skin out carcasses, turning the hide inside out while leaving much of the skeleton intact, with the lower legs and skull still joined to the hide. On very young animals, however, the ribs often are neatly clipped off close to the backbone and eaten. Eagles frequently do not eat the breastbone, but some clip off and eat the lower jaw, nose, and ears. Quite often, they remove the palate and floor pan of the skull and eat the brain. They may clean all major hemorrhages off the skin, leaving very little evidence of the cause of death, even though there may be many talon punctures in the skin. Ears, tendons, and other tissues are sheared off cleanly by the eagle’s beak.
Larger carcasses heavily fed on by eagles may have the skin turned inside out with the skull, backbone, ribs, and leg bones left intact, but with nearly all flesh and viscera missing. The rumen normally is not eaten. Eagles may defecate around a carcass, leaving characteristic white streaks of feces on the soil. Their tracks may be visible in soft or dusty soil. Small downy feathers often are evident on vegetation where eagles have fed.
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