Diclofenac, a commonly used pain killer, could be responsible for the vanishing vulture population in India. Experts say other birds too can be harmed by this drug.
Diclofenac is prescribed to cattle to prevent joint pains. Vultures die after eating dead cattle which has been administered with the chemical.
The pain killer does not require a prescription and comes cheap. Doctors say, “Approximately 65 per cent of the drug is excreted via the kidneys in the form of metabolites and less than 1 per cent in unchanged form. About 35 per cent of the dose is excreted in metabolised form.”
Dr Nagaraj, a veterinarian with the Forest Department, says, “The amount of Diclofenac that is leached through sewage into water bodies is very low. All birds are definitely harmed by it, but the process may be slow because of the low amount of Diclofenac. The fact remains that it is harmful to all birds.”
A paper by Dr S K Mukhopadhyay of West Bengal University of Animal and Fishery Sciences, Kolkata, says, “During the 1980s, there were nearly 40 million vultures in India. The alarming population decline was recorded in the late 1990s by the Bombay Natural History Society (BNHS). Three Gyps species are on the verge of extinction due to use of Diclofenac in livestock in India, Nepal and Pakistan. Due to this, 95 per cent of vulture population has declined and only 60,000 of these scavengers are left.”
International Species Recovery Officer for Royal Society for the Protection of Birds and Asian Vulture Programme Director Chris Bowden spoke at a conference in the city on conservation challenges recently. He said, “Around 20 years ago, vultures were found in plenty in India, but all the three species are getting extinct. I was roped in from the UK to be a part of Saving Asia’s Vultures from Extinction. We have succeeded in identifying the cause of death as the chemical Diclofenac.”
He said, “Veterinary formulations are almost gone but human formulations are still around. We got the first bird fledged in captivity in 2008 and we have 92 of them now.”