Turkey VulturesVultures are large birds of prey closely related to hawks and eagles. They are divided into New World vultures and Old World vultures, both belongingto the order Falconiformes. The New World vultures, in the family Cathartidae,consist of seven species in five genera.
Among the New World vultures includethe Cathartes aura, also known as the Turkey Vulture. Scientists say that turkey vultures are shy, inoffensive birds. Someresearchers have discovered that the bird is very helpful to the environment. Its habit of cleaning up decaying and diseased carcasses makes it a sanitaryengineer par excellence, while its keen sense of smell has been pressed intoservice to find wasteful and dangerous gas leaks. And the vulture’s uniqueknack for conserving energy has intrigued scientists for years. Although the turkey vulture has a large, turkeylike body and sporty redhead, it is not even distantly related to the turkey.
Instead, turkey vultures-along with their cousins in the United States, the black vulture of the Southand East, and the nearly extinct California condor-belong to a group of raptorscalled New World vultures. Chromosome analysis shows that the New Worldvultures are actually more closely related to storks than to the vultures ofEurope, Asia, and Africa. Turkey vultures are remarkably successful birds. They range everywherefrom parts of Canada and much of the United States to South America. At home indeserts, prairies and woodlands, they have even settled close to people in anumber of urban and suburban areas. Observed in flight, the turkey vulture appears black with the undersideof its wings grayish or silvery, giving the birds a two-toned appearance.
Theycharacteristically hold their wings in a slight V, or dihedral, thus aidingidentification. On rare occasions, they hold their wings flat and eagle-likewhich, if seen at a great distance, may cause the birds to resemble eagles. Inflight, the turkey vulture holds it’s naked head, crimson-red as adults andgrayish-black as immatures, downward in contrast to eagles, which hold theirheads forward. The tail of the turkey vulture extends far beyond the rear edge of itswings. They typically rock or tilt from side to side while gliding or soaringon updrafts or circling overhead.
Their occasional wingbeats are powerful andlabored. Turkey vultures are large birds with wingspreads of about six feet. Their wings are long, moderatly wide, and have strongly slotted tips. Typically,the wings are held slightly above a horizontal plane when the bird is aloft. This forms a characteristic dihedral which is very useful in making correctfield identification. Although turkey vultures use thermals, they are moredependant upon updrafts when migrating along mountains.
The birds use the aircurrents skillfully and seldom exert much energy by flapping their wings. Much of the credit for the bird’s success, scientists say, belongs toits efficient use of energy. Turkey vultures are marvels of energy conservation. It seems a turkey vulture’s whole life is spent trying to conserve every littlecalorie it gets. If there’s some small way it can save burning its own body fatand tissue, it will. Like an energy-conscious homeowner, a vulture turns downits thermostat at night.
During the night, a turkey vulture’s body temperaturedrops a few degrees. The result is a savings in the vulture’s energy bank. Towarm up again in the morning without burning much fuel, the prehistoric-lookingbird spreads its wings and soaks up all the sun it can. Another trick performed by the turkey vulture is a behavior calledurohidrosis.
Like all birds, the turkey vulture has no sweat glands. To coolitself during hot spells, it frequently defecates on its own legs. The slurryof white uric acid in the feces contains mositure that cools by evaporating. The behavior, shared by other vultures and storks, is more efficient thatsweating since it requires no boost in metabolism. The turkey vulture’s most basic ploy for saving energy is simply stayingput.
If the weather is bad for flying, they can and will sit at their roost fordays. Since their metabolism is low compared to many other birds, fasting seemsto bother them little, if at all. This ability to go without food comes inhandy for another reason. The animal’s food supply is extremely unpredictable. They don’t know where their next meal is coming from. The birds are well-equipped to get that next meal though.
Compared withthe heavier, chunkier black vultures, turkey vultures have light bodies and long,broad wings which provide excellent lift. They don’t use or lose a lot ofenergy landing and taking off, so they’re able to exploit small food itemsefficiently. As a result, you’ll often see a turkey vulture at a road-killedmouse, something the black vulture wouldn’t consider doing. Turkey vultures are also masters of effortless flight.
By ridingthermals, they can search for carcasses over dozens of square miles with only afew flaps of their wings. From a vulture’s point of view, finding a carcass isa race against time. Not only do vultures have to beat mammalian scavengers,already on the ground ready to follow a scent trail to the prize, but they alsohave to find the body before insects render it an inedible, maggot-ridden soup. The turkey vulture’s total dependence on its sense of smell to find foodin the forest can be easily demonstrated by putting out carcasses, some leftuncovered and some hidden completely by a pile of leaves. The birds find thehidden carcasses just as quickly as those in the open. Turkey vultures hunt byflying just above the level of the tree canopy, sniffing the air all the time.
As soon as they get a whiff of rotting meat, they start to circle to determinewhere the aroma is strongest. They then fly down into the forest, following thescent trail from tree to tree, until they are led to their reward on the forestfloor. Because an airborne bird on the scent is usually within sight of manyothers that are quick to follow, good numbers of vultures of various species cancongregate at a carcass within minutes. Turkey vultures could not detect carrion less than about twelve hoursold. A carcass twenty-four hours old, however, emits a sufficient stench toattract vultures readily.
These birds have a reputation for savoring stinking,rotting meat, but when offered a choice of relatively fresh or rotting meat,they strongly preferred the fresh. Badly decayed meaat contains unpleasantbacterial compounds that either impede digestion or are actively toxic. Vultures will eat rotten meat if they are extremely hungry, but if they are notshort of food, they will give bad meat a miss and wait for the scent ofsomething more palatable. Turkey vultures can tell from the smell comingthrough the tree canopy how long an animal has been dead, probably because thesmells given out by the bacteria that develop in meat change with the age of thecarcass. Thus, vultures do not even bother to fly down to old carcasses asoften as they do to day-old carrion. Only turkey vultures can locate food bysmell; black and king vultures lack this ability completely.
Once the scavenging birds find something dead in the wild, another setof unique abilities comes into play. Since decaying meat is not the mosthealthful of foods, turkey vultures have evolved into veritable detoxificationplants. Not only can they eat food so rotten that it could kill most othercreatures, they benefit people and the environment by preventing the spread ofdiseases. Among these is botulism, a deadly sickness caused by a bacterialpoison that attacks nerve-muscle junctions and leads to death by suffocation. Biologists have found that turkey vultures have both botulism-resistant nervoussystems and heavy duty immune systems that ward off the bacterial toxin.
In oneexperiment, a scientist injected one turkey vulture with a dose of botulinustoxin lethal enough to kill 300,000 guinea pigs. The bird never showed a moment’s illness. But while turkey vultures are formidable foes of bacteria, they are shy,cautious and docile when confronted by virtually any creature larger than amicrobe. This shyness is often carried to an extreme. When the birds aretrapped and handled, they are totally docile. Being submissive is only one waya turkey vulture acts when stressed.
When frightened, they tend to regurgitate. Whether the act is intentional or not, it provides the dual benefit oflightening the load for a quick getaway and repelling any would-be antagonistwith the stomach content’s foul odor. The turkey vultures’ foul and sinister reputation, however, finallyseems to be changing. In fact, the infamous scavengers are actually findingthemselves appreciated by some people.
Each year, for example, thousands ofpeople jam the town of Hinckley, Ohio, on one Sunday in March. The occasion iscalled Buzzard Day. This is the day that the vultures are scheduled to drift infrom their southern wintering grounds. People from all over the area gather towatch their beloved birds reappear.
Vultures are large birds of prey closely related to hawks and eagles. They are divided into New World vultures and Old World vultures, both belongingto the order Falconiformes. The New World vultures, in the family Cathartidae,consist of seven species in five genera. Among the New World vultures includethe Cathartes aura, also known as the Turkey Vulture. Scientists say that turkey vultures are shy, inoffensive birds. Someresearchers have discovered that the bird is very helpful to the environment.
Its habit of cleaning up decaying and diseased carcasses makes it a sanitaryengineer par excellence, while its keen sense of smell has been pressed intoservice to find wasteful and dangerous gas leaks. And the vulture’s uniqueknack for conserving energy has intrigued scientists for years. Although the turkey vulture has a large, turkeylike body and sporty redhead, it is not even distantly related to the turkey. Instead, turkey vultures–along with their cousins in the United States, the black vulture of the Southand East, and the nearly extinct California condor-belong to a group of raptorscalled New World vultures. Chromosome analysis shows that the New Worldvultures are actually more closely related to storks than to the vultures ofEurope, Asia, and Africa. Turkey vultures are remarkably successful birds.
They range everywherefrom parts of Canada and much of the United States to South America. At home indeserts, prairies and woodlands, they have even settled close to people in anumber of urban and suburban areas. Observed in flight, the turkey vulture appears black with the undersideof its wings grayish or silvery, giving the birds a two-toned appearance. Theycharacteristically hold their wings in a slight V, or dihedral, thus aidingidentification. On rare occasions, they hold their wings flat and eagle-likewhich, if seen at a great distance, may cause the birds to resemble eagles. Inflight, the turkey vulture holds it’s naked head, crimson-red as adults andgrayish-black as immatures, downward in contrast to eagles, which hold theirheads forward.
The tail of the turkey vulture extends far beyond the rear edge of itswings. They typically rock or tilt from side to side while gliding or soaringon updrafts or circling overhead. Their occasional wingbeats are powerful andlabored. Turkey vultures are large birds with wingspreads of about six feet. Their wings are long, moderatly wide, and have strongly slotted tips. Typically,the wings are held slightly above a horizontal plane when the bird is aloft.
This forms a characteristic dihedral which is very useful in making correctfield identification. Although turkey vultures use thermals, they are moredependant upon updrafts when migrating along mountains. The birds use the aircurrents skillfully and seldom exert much energy by flapping their wings. Much of the credit for the bird’s success, scientists say, belongs toits efficient use of energy. Turkey vultures are marvels of energy conservation.
It seems a turkey vulture’s whole life is spent trying to conserve every littlecalorie it gets. If there’s some small way it can save burning its own body fatand tissue, it will. Like an energy-conscious homeowner, a vulture turns downits thermostat at night. ful of foods, turkey vultures have evolved intoveritable detoxification plants. Not only can they eat food so rotten that itcould kill most other creatures, they benefit people and the environment bypreventing the spread of diseases.
Among these is botulism, a deadly sicknesscaused by a bacterial poison that attacks nerve-muscle junctions and leads todeath by suffocation. Biologists have found that turkey vultures have bothbotulism-resistant nervous systems and heavy duty immune systems that ward offthe bacterial toxin. In one experiment, a scientist injected one turkey vulturewith a dose of botulinus toxin lethal enough to kill 300,000 guinea pigs. Thebird never showed a moment’s illness. But while turkey vultures are formidable foes of bacteria, they are shy,cautious and docile when confronted by virtually any creature larger than amicrobe. This shyness is often carried to an extreme.
When the birds aretrapped and handled, they are totally docile. Being submissive is only one waya turkey vulture acts when stressed. When frightened, they tend to regurgitate. Whether the act is intentional or not, it provides the dual benefit oflightening the load for a quick getaway and repelling any would-be antagonistwith the stomach content’s foul odor.
The turkey vultures’ foul and sinister reputation, however, finallyseems to be changing. In fact, the infamous scavengers are actually findingthemselves appreciated by some people. Each year, for example, thousands ofpeople jam the town of Hinckley, Ohio, on one Sunday in March. The occasion iscalled Buzzard Day. This is the day that the vultures are scheduled to drift infrom their southern wintering grounds.
People from all over the area gather towatch their beloved birds reappear.
