International Vulture Awareness Day was celebrated worldwide earlier this month, with organizations representing more than 25 countries from Argentina to Zimbabwe holding special festivals and public programs. What is it about these ungainly and generally under-appreciated birds that is worth talking about and celebrating?
There are 23 species of vultures in the world: seven species found in the Americas (including the two very large vulture species we call condors) belong to the "New World" vultures; 16 species found throughout Eurasia and Africa comprise the "Old World" vultures. Although New World and Old World vultures are not closely related, they share many adaptations to a scavenging lifestyle. For example, all vultures have a mostly featherless head. This prevents bacteria in the dead animals they eat from ruining feathers that would quickly become covered in blood and rotten meat, and it exposes the vulture's skin directly to the sterilizing effects of the sun.
All vultures have very large wings that enable them to soar effortlessly on updrafts and thermals for hours as they search the ground below for carrion (dead animals). They also have excellent vision for locating animal carcasses on the ground, sometimes hundreds of feet below, but only a few species of New World vultures have an adaptation that is very rare in birds--a well-developed sense of smell. One of these is the familiar turkey vulture, a large dark bird commonly seen gliding on up-tilted wings over the hills of Pittsburgh. This species can detect the odor of a decaying animal carcass hidden from view below the cover of trees.
Vultures are uniquely adapted for finding, removing and recycling carrion that otherwise might promote the growth of disease-causing bacteria and other germs capable of polluting local food and water supplies and causing serious illnesses. The fact that nearly half of the world's vulture species is threatened with extinction is potentially a serious problem for people, too. Fortunately, conservation biologists have been successful in rescuing vultures from this threat. A heroic effort launched in the U.S. in the 1980s prevented the extinction of California condors, whose population had dropped to fewer than 25 birds due to persecution and habitat loss. Biologists captured all of the remaining condors and brought them into a successful captive breeding program. Today, more than 200 condors are again living and nesting in the wilds of Arizona (the Grand Canyon), northern California and Baja, Mexico.
The National Aviary is home to three species of vultures: six hooded vultures that have had starring roles in our "Wings!" show; a black vulture named Sarabi, who has appeared on our Skydeck and in our education outreach programs, including appearances on national television this spring; and a 28-year-old female Andean condor named Lianni, who has fledged two chicks at the National Aviary. One chick was released into the wild near Bogota, Colombia; the other was sent to the Cincinnati Zoo where, like its mother, it serves as a conservation ambassador for its species.