Vail Curious Nature: Scavengers of the sky
Vail, CO Colorado
AVON, Colorado – John Wayne, wounded by a gunshot, stumbles across the desert. He glances nervously towards the sky, eyeing the vultures that circle above, seemingly waiting for him to die.
The myth of vultures circling someone about to die, like many others, is just that, only another myth about wildlife. While turkey vultures would certainly be thrilled to feast on the Duke’s corpse, these gallant but misunderstood birds would probably be too busy sailing on the wind to pay attention to a lone cowboy stumbling through the desert.
Even ardent bird lovers tend to discount the lowly turkey vulture. Avidly scanning the skies to discern a raptor’s species, they disappointedly state that it is “just a vulture.” But while common, the turkey vulture is hardly ordinary. In fact, finely tuned adaptive features have honed this unattractive bird into a master of evolutionary precision. From its nearly bald head to its keen sense of smell, almost unique in the avian world, the turkey vulture has distinct behavioral and physical features that have helped it to survive and thrive.
Named turkey vulture because of its red head, the birds are recognizable by the dark leading edge of their wings and the whitish trailing edge. Vultures on the ground are clumsy and slow to take off, resulting in unfair fights with vehicles while trying to dine on road kill.
Watch for them whenever you see dead animals. If they’re not close by, they will be soon. Their keen sense of smell quickly alerts them to meal opportunities.
With its broad wingspan of nearly 6 feet, the turkey vulture is famous for its soaring ability to fly for over six hours without flapping once. The vulture’s secret is to wait until the cool morning air has warmed. The birds then launch from a perch, searching for thermals, or pockets of rising warm air. The thermal carries the birds upward as they circle lazily until they reach the thermal top. The birds then dive at speeds of 60 mph until they find another thermal. Floating far above the land like this enables vultures to expend minimal amount of energy while carefully smelling and scanning the ground for carrion.
In addition to dining on carrion, the turkey vulture has a few additional habits that contribute to its general repulsiveness. Urinating and defecating on their own legs may help vultures cool down, but it’s sure not going to make them any friends. The vulture further ingratiates himself with a lovely habit of vomiting to repel predators. The undigested meat provides a distraction in the form of an easy, but foul-smelling meal. To combat their generally unhygienic lifestyle, vultures are (thankfully) equipped with a strong immune system, complete with stomach bacteria designed to neutralize the pathogens that come as a side dish with an entree of carrion.
Until relatively recently, all vultures were classified as raptors, or birds of prey, with their habit of feasting on dead animals thought to simply be a variation on the theme of carnivorous birds. However, in 1994, scientists analyzed DNA and found that vultures in North and South America are actually more closely related to storks and other wading birds. Vultures from Europe, Asia, and Africa are now called Old World Vultures and are related to hawks and eagles, while the seven species of vultures inhabiting North and South America are labeled New World Vultures, grouped into the same order as egrets and herons.
Author Ed Abbey contemplated the turkey vulture many times in his writing, saying that after he died, he wanted to come back and live the peaceful life of a turkey vulture, circling high in the noonday sun and feasting on the table scraps of others.
“Let us praise the noble turkey vulture: No one envies him; he harms nobody; and he contemplates our little world from a most serene and noble height.”
I hope Ed is enjoying life from that serene and noble height.
Jaymee Squires is the graduate programs director at Walking Mountains (formerly Gore Range Natural Science School) and teaches students about all species of birds and animal, even the more disgusting ones. For more information, go to http://www.walkingmountains.org.