Food.--The inability of the vulture to kill its prey has forced it to play the part of a scavenger, and the struggle for existence has driven it further. Where the bird is abundant, it cannot, like other Raptores, select its victim; it has to accept what chance presents.
When death comes to any animal, its body becomes food for the vultures. As soon as the animal can no longer move, the meal is ready, and if a vulture finds a dead body, although it be warm from the life just flown, the bird begins at once to feed. But a large animal--a horse or a cow--cannot be finished, even by a company of voracious vultures, while the body is fresh. Putrefaction works fast and overtakes the birds, and the end of the meal becomes far advanced in decomposition. Also it often happens, owing to the position of the body, or because it is submerged, or because the hide is too tough for the vulture's beak to tear, that little or none of it is accessible to the birds. Then the vultures gather about the carcass in large numbers, if it be a big one, and wait patiently near at hand until time and decay, making it soft and ripe, shall fit it to their needs. Then they descend and strip it to the bone.
Thus evolution has led the vulture in its search for food away from the other Raptores and has compelled it to develop feeding habits that it shares with few companions among birds and mammals.
The vulture shows apparently little preference in its choice of food. It is a useful bird in the Southern States, where it disposes of the dead animals about the farms, and, as Dr. Pearson (1919) says, "in many a southern city the Vultures constitute a most effective street-cleaning department, and the garbage piles on the city's dump-heaps are swept and purified by them. When the rancher of the West dresses cattle for home consumption or the market, his dusky friends in feathers gladly save him the trouble of burying the offal."
Wright and Harper (1913), writing of the Okefinokee Swamp, remark that "it is astonishing how soon the buzzards appear over a spot where an alligator has been shot, and how quickly they transform its carcass into a bare skeleton."
Florence A. Merriam (1896) reports from California that Mr. W. W. Merriam watched two of the buzzards eating skunks. They began by pulling the skin from the head and ate till they came to the scent gland, which they left on the ground."