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By Diane Dragotto Williams
At Wildhaven Ranch, we have been amused by the gross and the ugly wild creatures, as well as the attractive.
Certainly, the Turkey Vulture, Cathartes aura, with its disgusting behaviors, and peculiar face qualifies! Getting its name from the red skin on its head and dark body feathers that resemble a turkey, this carrion feeder is common to the United States and seen in habitat from woodlands and farms to the desert. Gliding over open country, looking for food which it finds by its scent, it often roosts in flocks, and many birds will converge to feed at a carcass. It prefers meat to be ripe, making it easier to strip off the bones, and for the bare head to be bacteria free after engorging on a bloody mess.
Soaring birds hold their wings above their back in a shallow V called a dihedral and rock side to side as if unsteady in the air. Circling above treetops and up to 200 feet high, they are a master at flying. Turkey vultures frequently circle and gain altitude on pockets of rising warm air, or thermals. When they reach the top of the thermal, they glide across the sky at speeds up to 60 miles per hour, gradually losing altitude all the while. When they need to gain more altitude, they locate another thermal and so begins another sequences of circling, rising, and then gliding. Turkey vultures can cover many miles going from thermal to thermal without ever needing to flap.
Twenty-five to 32 inches long, with a wingspan around 6 feet a healthy adult turkey vulture can weigh approximately 5 to 6 pounds. Nesting on the bare ground, in caves, rock outcroppings, hollow trees and even empty buildings, these avians have few predators. Except man, golden eagles and large mamals that may take adavantage of their presence on the ground, their eggs or nestlings can be taken by bald eagles, great horned owls, raccoons, opposums and foxes. Turkey vultures have weak, chicken-like feet, which are suitable for running on the ground but not for grasping and cannot lift or carry food with their feet. They can only step on their food to hold it in place while eating. Without a voice box, turkey vultures either hiss or grunt, or sometimes growl around food, which gives them their only appearance of aggression. Though the bulk of their food is carrion, they sometimes eat rotten fruit and vegetables, stranded mussels, shrimp and fish, and even coyotes and sea lion feces.
Standing in a spread wing pose, the turkey vulture warms and dries itself in the morning sun to rid itself of bacteria and bring its temperature up from its night time almost hypothermic degrees to save energy. Efficiency a standard, and unable to sweat, on warm days, urinating on its legs cools the vulture as the urine evaporates. In addition, this urine contains strong acids from the vulture’s digestive system, which may kill any bacteria that remain on the bird’s legs from stepping in its meal.
But their most disgusting behavior experienced by us at Wildhaven Ranch is vomiting at will. Usually this is done as a means for vultures to off-load some weight as predators approach when the vulture has eaten too much to fly. But they will also regurgitate under stress or to keep anything threatening at bay. Also semi-digested food can be offered up to a predator as an easy meal instead of attacking the intended vulture!