Turkey Vultures

Kali is a Turkey Vulture at Cascades Raptor Center in Eugene, Oregon.

Photos and text by Dan Gleason, © 2011

The Turkey Vulture is one of our most misunderstood birds and while it may only pass over your yard, it is a bird that we really do not want to be without. Vultures are scavengers, feeding only on carrion. They are our “clean-up committee” and we owe them many thanks. They belong to the genus, Cathartes, from the Greek meaning one who cleans or purifies. Because vultures only eat dead animals, we might feel repulsed by their diet, but try to imagine how awful it would be if all of those carcasses they normally consume were simply left untouched. In fact, no imagination is needed: just look to India.

In much of India, 95% of their vultures (3 species) have disappeared; from 40 million birds in the 1980s to about 60,000 today. Why this massive decline? Cattle are sacred in India, so are not eaten and carcasses are left in fields for vultures to consume. But, when an anti-inflammatory drug, diclofenac, was given to cattle, and those dead cattle were eaten by vultures, the drug caused fatal kidney failure in the birds, even in small doses. Thus, vulture populations were decimated. They were replaced by packs of roaming dogs, and an increase in rats and other pests. Vultures can completely clean up a carcass in a matter of hours, but dogs leave much of it to rot and become disease-ridden. Dogs can also spread disease, especially rabies, and as the vultures disappeared, disease increased. India now has the highest human death rate from rabies—25,000–30,000 people annually.

Turkey Vultures have powerful digestive systems and even organisms causing such diseases as anthrax, salmonella and botulism are destroyed. reducing the potential spread of these diseases. Vultures prefer a fresh carcass, but often have no choice and must eat whatever they find. Contrary to popular belief, vultures do not circle overhead waiting for something to die. They also cannot catch or carry prey; even a small carcass, like a squirrel. Their foot structure and weak talons make that impossible, so a vulture must feed wherever it finds food. Road-kill provides a food source, but they risk being hit by on-coming vehicles. Slow to take wing, they may be heavy if they have just gorged themselves. Once airborne, however, a vulture is a master of the air and glides long distances, seeking its next meal.

Notice the large nostrils associated with the Turkey Vultures keen sense of smell.

Turkey Vultures’ sense of smell is very keen and they find their food by smell, whereas most other birds (including other vultures) have a very limited sense of smell. Turkey Vultures can smell chemicals called mercaptans which occur naturally in the brain and abdomen of animals and are released at death. We know this smell because it is put into natural gas, giving it the tell-tale scent of rotten eggs. Natural gas has no odor and by adding mercaptans, humans are able to easily detect a leak by smell. Turkey Vultures are even better at detecting this smell and follow air-borne scent trails to seek food.

The featherless head of a vulture is very important. Turkey Vultures are typically the first to open a large carcass and other scavengers stand aside and wait for the vultures to do their work. In doing so, feathers could become matted with the flesh of the carcass. Birds preen and clean their feathers by using their beak, but they can’t use their beak to clean their head. Thus, a head without feathers ensures that there are no feathers to clean, and any debris can be scraped off with the foot, or baked off by the sun. This is a very efficient adaptation, but some people find a featherless head unattractive. Knowing the reason for a bald head, I would suggest a visit to Cascades Raptor Center in south Eugene. Here you can see these birds up close to observe them and their behavior to better appreciate them, as they are very intelligent and inquisitive birds.

Despite feeding on dead carcasses, vultures are very clean, having fewer lice and other parasites than do most songbirds. They are devoted parents and life-long mates, seeking another mate only if their original mate dies.

Here, in the western United States, Turkey Vultures tend to migrate longer distances than vultures in the east or the Southwest. Some of our area’s vultures migrate only to California, but many travel all the way to Central and South America for the winter, often not feeding as they pass through Central America. They are among the first migrants to return to western Oregon, often arriving by the end of February and they are among the last to leave, sometimes staying until late October or mid-November. A few birds are usually now found wintering in the southern Willamette Valley, but it is unknown if these are birds from further north or if they bred here during spring and summer.

Turkey Vultures are sometime called “buzzards”, but that is incorrect because buzzard is the European name for a particular hawk, in the same genus as our Red-tailed Hawk. But whatever you call our vultures, do so respectfully. Vultures are wonderful, highly intelligent animals and through their actions, our world is a cleaner and safer place to live.

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