Monday, August 30, 2010

Meet the Vultures

In the United States, turkey vultures are often seen along the side of the road eating roadkill or soaring high in the sky looking for carrion.  The only other vulture you may see in the U.S. is the black vulture.  These are two of the seven species of New World vultures (family Cathartidae) that inhabit North and South America.  California Condors and Andean Condors are also of the seven in this grouping.  At the World Bird Sanctuary, turkey vultures can be seen on our display line and you may also see our newest education turkey vulture, Kinsey, at our Nature Center.
Me (Sara Oliver) with our young Turkey Vulture, Kinsey
Dorothy our Andean Condor will make her debut appearance on International Vulture Awareness Day on Saturday September 4th at the sanctuary!
Dorothy, our young Andean Condor
There are sixteen species of Old World vultures (family Accipitridae) that inhabit Africa, Europe, and Asia.  This family also includes eagles, kites, and hawks.  Old World vultures find carrion exclusively by sight, whereas several species of New World vultures, especially turkey vultures, are able to find the dead with a sense of smell, which is unusual for birds of prey. 

Vultures are scavengers.  They are Mother Nature’s garbage crew.  They consume dead, rotting animals which are often infected with bacteria that could kill most other animals.   Thus, vultures prevent disease from spreading to other animals.  They do not become sick from the carrion they consume because vultures have a very acidic stomach, with a pH of around 1.  (On the pH scale 7 is considered neutral – 0 to 1 is the range for battery acid).  This allows them to safely digest putrid meat infected with botulism, hog cholera, and anthrax bacteria.  Vultures keep our forests, grass plains, and savannas healthy.  Without them we could be deep in an accumulation of rancid carcasses.
Fred, our Hooded Vulture
Unfortunately, vulture populations have been dwindling, to the extent that some are termed nearly extinct, endangered or vulnerable.  For example, the Cape Griffon Vulture is listed as a species vulnerable to extinction.  Native to a small range in south and southwest Africa, these vultures face dangers such as electrocution on power lines.  Of more concern, mass amounts of vultures are killed at one time through accidental poisonings.  It is common for farmers and ranchers in parts of Africa to poison the bodies of dead livestock in order to kill predators like leopards and jackals which also prey on their live animals.  The vultures gather in large groups to feast on this free banquet.  One carcass can attract 50 to 500 birds leading to high death toll all at once.  Researchers have begun applying satellite telemetry collars to these birds to track their movements and give information on the sources of contaminants in their range.

In India, Pakistan and Nepal, vultures are dying when they consume dead livestock that had been treated with a pain relieving drug called diclofenac.  The drug is harmless to humans, but it causes kidney failure in vultures.  They are in steep decline in south Asia, and as a result more carcasses are piling up and feral dogs and rats are increasing in numbers, feeding on the waste the vultures would have eaten.  As the number of feral dogs increase, so do rabies and the number of people bitten by a rabid dog.  The only thing that can stop this slippery slope is the ban of diclofenac.

The California condor is labeled as critically endangered.  The threats they face include lead poisoning from eating animals containing lead bullets, collisions with electric power lines, habitat destruction, and poaching.  In some parts of the western United States, this species was driven to the brink of extinction by cattle ranchers who observed condors feeding on dead calves and assumed the birds had killed them.  Conservation efforts for this species include a captive breeding program and release of captive-reared adolescents.

Another conservation effort being done to help these birds is “vulture restaurants” where fresh and poison-free carcasses of livestock or wild mammals are put out for vultures to enjoy. 

Efforts to protect vultures require cooperation and support at international, national, regional and individual levels.  You can help in this cause.  Support conservation organizations and breeding programs for endangered vulture species.  Do not use poison to kill wildlife.  Eliminate pesticide use.  Do not use lead bullets when hunting.  Recycle forest products to decrease the need to cut down trees in which vultures roost.  And, lastly, report roadkill so it can be removed to protect vultures from being hit by cars. 

Join us for International Vulture Awareness Day at the World Bird Sanctuary on Saturday, September 4th from 10 am to 3 pm!  As always, admission and parking are free.  International Vulture Awareness Day is sponsored by AmerenUE.

Submitted by Sara Oliver, World Bird Sanctuary Naturalist


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