BOISE, Idaho – Despite their value to humans and the environment, vultures continue to experience serious population declines that are made worse by government inaction and a lack of funding for skilled experts to address the problem, according to a paper to be published in the March issue of the Annals of the New York Academy of Sciences.
The peer-reviewed article is co-authored by Darcy Ogada and Munir Virani of The Peregrine Fund and Felicia Keesing of Bard College. It is available online at:
Currently, 61% of vulture species worldwide are threatened with extinction, the authors said. The worst population declines have occurred in South Asia and Africa, where the scavenging birds are unintentionally poisoned, shot for food or sport, and killed for superstitious reasons. Populations of some species have declined by up to 99% in a decade.
They said the vulture crisis highlights the importance of collaboration among scientists, regional governments, financial donors, and media to conserve these ecologically important birds throughout their large range. The authors urged greater support and backing from national governments and local communities, particularly in Africa.
In Asia, the vulture crisis has received widespread attention, resulting in more stable vulture populations and captive breeding programs. In Africa, however, where the vulture crisis is equally dire, little effort is being made to raise awareness and address the problem, the authors said.
Deliberate poisoning of lions and other large carnivores that occasionally prey on domestic livestock appears to be the biggest culprit in Africa. Vultures die in large numbers after eating the poisoned bait.
“In many African countries, vulture populations remain little known and even less is being done on the ground to ensure their survival,” they said. “There has been little government support to conserve vultures, despite mounting evidence of the major threats.”
The loss of vultures has potentially significant effects on humans. The scavenging birds perform a vital service by consuming dead animals that would otherwise spread disease and contaminate land and water resources. The article also cites evidence that vultures are important to other scavenging animals that don’t have the ability to soar far above the landscape to locate carrion.
“Scavenging of carcasses by vultures promotes the flow of energy through food webs, and vultures have been shown to facilitate African predators, such as lions and hyenas, in locating food sources,” the authors said.
In Asia, the problem is the result of the veterinary use of diclofenac, a drug that is toxic to some vultures species in residual amounts found in livestock that die following treatment. After The Peregrine Fund discovered the effect of diclofenac on vultures in 2003, India, Pakistan, Nepal, and Bangladesh banned the veterinary use of the substance. Although populations of some vulture species now appear to be stabilizing, much more needs to be done to educate farmers who continue to use the drug illegally to treat ailing animals that later die and are left to scavengers, the authors said.