The turkey vulture, Cathartyes aura, scavenges in the fields and along the roadsides for dead game or roadkill. You can see it soaring in wide circles with its wings in the shape of a broad "V" as it tilts from side to side. Its wings are two-toned, and immature turkey vultures have black heads. When a turkey vulture finds food, it swoops down on it. Other vultures flying beyond human vision quickly join in.
Turkey vultures generally eat dead animals. They do not usually kill animals but there have been a few reports of vultures feeding on weak or helpless animals. These reports are very rare and include animals like baby rats, grouse chicks or small fish. Turkey vultures will not eat any rotten meat; however, some meat is too rotten even for a vulture. It prefers fresh meat but will eat decayed meat if that is all it can find. It tends to pass by the carcasses of carnivorous animals, but will eat it if it can't find herbivore .
Unlike vultures in other parts of the world, turkey vultures' sense of smell is well-developed. Scientists have learned about this quality through the behavior of vultures around leaks in natural gas pipelines. For human safety, the chemical mercaptan, which smells like carrion, has been added to natural gas. Vultures will circle leaks where someone has added this chemical. In addition to their keen sense of smell, they have excellent eyesight during the day, though poor night vision. Scientists are not sure which sense is better-developed. They theorize that in areas such as tropical environments where much is hidden, the vultures learn to rely more on their sense of smell. Therefore, it is better developed in birds living in that environment.
Some observers think that circling vultures are an indication something on the ground is dead, but this is not necessarily true. Circling vultures may have found food below, but it is just as likely they are playing or attempting to gain altitude. Vultures soar upward on thermal belts of warm air in order to glide more effortlessly in their search for food. When vultures are circling food, they will circle longer when the game is large. They notify other vultures so that they will dispatch the carcass more quickly. If the game is small, the vulture will descend rapidly to dispose it.
