“Only a decade ago, millions of Asian vultures lived in Pakistan, India, and Nepal. These enormous raptors provided an effective method of removing dead livestock, preventing the spread of diseases. They played a similar role with human corpses, ritualized in the “sky burials” of the Parsi religion.
…
“Then huge numbers of these birds began dying mysteriously starting about a decade ago.”
Not necessarily unusual by itself, the case of the three Asian vultures (long-billed, oriental white-backed, and slender-billed) follows an unusual path, providing yet another case study for us to to file away under the heading of “unintended consequences.”
One prominent theory—now supplanted—cast the blame on some fearsome ‘mystery virus’:
“Vultures were almost as common as sparrows in India. But the arrival of a mystery virus a decade ago has wiped out 95% of the species, and some scientists believe the gawky birds are on the brink of extinction.” (Reuters)
Which was maybe reasonable-sounding, however wrong it was. Now we find out that the cause has to do with humans:
“[The vultures are] now teetering on the edge of extinction. No one knew why until last May, when a veterinarian with the Peregrine Fund discovered the culprit: a pain-relief medication routinely administered to cattle. Birds that ate dead cattle treated with the drug were dying in massive numbers. ” (CSMonitor)
What wonders, these cattle-drugs.
links:
- Christian Science Monitor: “In divided area, a drive to save vultures” by Rachel Dickinson (March 4, 2004)
- ABC [Australian Broadcasting Corporation] Online: “Mystery virus pushing Indian vultures to extinction” (May 21, 2003)
further information:
- Peregrine Fund Asian Vulture Population Project
- Peregrine Fund: “Veterinary Use of the Drug diclofenac Found to Cause the Collapse of Vulture Populations in South Asia” by Rick Watson, Ph.D. (Jan 28, 2004)