Vulture numbers rise up for first time in 20 years, study shows

CHENNAI: The country’s vulture population has increased for the first time in two decades, after a catastrophic decline in their numbers by more than 99%. A research paper by scientists from the Bombay Natural History Society (BHNS) shows that the number of vultures, once found across the country, increased marginally between 2011 and 2012.

The vulture population in India started to fall dramatically in the early ’90s. Around 95% of the big scavenging birds were wiped out by 2003 and more than 99% by 2008, and their numbers decreased from 4 crore in the early ’80s to less than 1 lakh in 2011. The study also warned that while the stabilization in vulture numbers is encouraging, only a small number of the birds remain and they are still extremely vulnerable.

Diclofenac, a painkilling drug administered to cattle, was the culprit. Vultures, which have a digestive system robust enough to even digest disease-causing pathogens found in rotting meat of dead, do not have a critical enzyme that breaks down diclofenac and die of renal failure after eating carcasses of cattle administered the drug.

“It’s lethal for vultures if they eat an animal within 72 hours of it being given diclofenac,” said Vibhu Prakash, lead researcher of the study and the deputy director of BNHS.

'Numbers offer hope'

Environmentalists said the increase in vulture numbers offered signs of hope for the critically endangered species once believed to be close to extinction.

A ban on the use of diclofenac across South Asia in 2006 led to a drop-off, between 2007 and 2011, in the numbers of birds being killed by the use of the drug on livestock. Ornithologists said the vulture population had stabilized by 2011, when the numbers remained roughly the same as the previous year.

“Between 2011 and 2012, there has been a slight increase in the population,” said Vibhu Prakash, deputy director of Bombay Natural History Society and lead researcher of a recent study on the subject.

He said getting a fix on the actual numbers was not immediately possible but the numbers are slightly higher than in 2011, when there were only 1,000 slender-billed vultures (Gyps tenuirostris), 11,000 white-backed vultures (Gyps africanus) and 44,000 Long-billed vultures (Gyps indicus) remaining in the country.

The decline prompted the International Union for Conservation of Nature (IUCN) to put vultures on its list of ‘critically endangered’ species.

The three most common species of vultures in the country are the long-billed vulture (Gyps indicus), also known as the Indian vulture, the white-backed vulture (Gyps africanus) and the slender-billed vulture (Gyps tenuirostris).