What happened to the circling vultures?
From ANIMAL PEOPLE, September 2004:
NEW DELHI–“The government is taking its own sweet time in
phasing out a veterinary drug blamed for bringing vultures to the
verge of extinction,” Chandrika Mago of the Times of India news
network charged on September 8, 2004.
Washington State University microbiologist Lindsay Oaks in
January 2003 identified the anti-inflammatory drug diclofenac as the
cause of the loss over the past decade of more than 95% of the once
common Oriental white-backed vulture. Also fast declining are
long-billed and slender-billed vultures.
“Vultures have an important ecological role in Asia, where
they have been relied upon for millennia to clean up and remove dead
livestock and even human corpses,” explained Peregrine Fund
biologist Munir Virani when the diclofenac link was disclosed.
“Their loss,” Virani continued, “has important economic,
cultural, and human health consequences,” especially for millions
of Parsees, about 1% of the Indian population, for whom exposing
corpses to consumption by vultures is a religious mandate.
The Bombay Natural History Society warned in February that
continued sale of diclofenac could cause the extinction of Indian
vultures. A similar warning came in June from Samar Singh,
president of the Tourism & Wildlife Society of India. Yet diclofenac
is still in unrestricted over-the-counter veterinary use.
The form of diclofenac used by humans is not at issue.
Except in consuming arthritic Parsees, vultures rarely come into
contact with residual diclofenac in human remains, and if that was
the vultures’ only source of risk, the vulture population probably
would not have fallen.
By far the greater risk comes from Indian and Pakistani
farmers who use diclofenac to keep lame oxen, buffalo, and equines
on the job pulling carts and plows. When the animals die, their
carcasses are left for scavengers. Residual diclofenac does not seem
to harm dogs or jackals, but cumulative exposure causes kidney
falure in vultures.
“There can be a population fall of 30% a year if less than
one in 200 carcasses available to vultures contain lethal amounts of
diclofenac,” Ornithological Society of Pakistan expert Aleem Khan
told Agence France-Presse. “Two hundred vultures can feed on the
carcass of a single big buffalo.”
Taking diclofenac off the market will require replacing it with
something equally effective and inexpensive.
To help vulture recovery, once diclofenac is banned from use
in animals, the British-based Royal Society for the Protection of
Birds in July 2004 agreed to fund captive breeding centers for
vultures in Haryana, Himachal Pradesh, and West Bengal. The
centers are to be managed by the Bombay Natural History Society.