Dying away

Print edition : May 21, 2010

A White-rumped vulture, previously known as the Oriental White-backed vulture, photographed near Kolkata.-SUVRASHIS SARKAR

FOR the three endangered species of Gyps vultures in India, 2009 was a year of mild optimism. Hornbill, the magazine of The Bombay Natural History Society (BNHS), reported that the first-ever captive-bred nestlings of the Slender-billed vulture (Gyps tenuirostris) had fledged successfully; that three pairs of Oriental White-rumped vultures (Gyps bengalensis) had bred successfully; and that two White-rumped vulture nestlings born in 2007-08 were also doing well. Apart from all this heartening activity at the Societys Vulture Conservation Breeding Centres in Pinjore, Haryana, and Rajabhatkhawa, West Bengal, there was the good news that another centre would soon become operational in Rani, Assam, and that land for a fourth centre had been acquired in Madhya Pradesh.

India is home to nine species of vultures, of which five belong to the genus Gyps. Three Gyps vultures Gyps tenuirostris, Gyps bengalensis and the Long-billed Gyps indicus are resident species and face the threat of extinction. The Himalayan griffon, Gyps himalayensis, and the Eurasian griffon, Gyps fulvus, are winter visitors.


Until two decades ago, there were about 40 million vultures in India and the bird was said to be as common as the crow. Now it is believed that there are around 60,000 of them. Ironically, the very density of the birds population disguised its decline. The loss was noticed only in 1997 when a BNHS team noticed fewer birds in a colony of White-rumped vultures in the Keoladeo Ghana National Park in Bharatpur in Rajasthan.

The urgency of the situation can be assessed by a simple statistic. In the 1990s, the White-rumped vulture was considered the worlds commonest large bird of prey. By 2000 there were no breeding pairs of the White-rumped left in the colony in Bharatpur. Between 1996 and 2006 there was a 97 per cent decline in the vulture population. Considered to be the fastest fall in numbers of any one species, the phenomenon came to be called the Asian vulture population crash. From being among the commonest birds of prey, all three resident species of Indian Gyps vultures were put on the International Union for the Conservation of Natures (IUCN) Red List of Threatened Species a status given to critically endangered species or species marked for extinction unless drastic measures are taken to save them.

Slender-billed vultures at the Pinjore vulture conservation centre in Haryana.-VIBHU PRAKASH

The last published survey on the status of vultures was carried out between March and June 2007 by Dr Vibhu Prakash and his team. Prakash is principal scientist at the BNHS and heads the vulture breeding programme. The survey, which was published as a paper, Recent Changes in Populations of Resident Gyps Vultures in India, revealed that the population of the three species of vultures continues to decline at an alarming rate.

It said: Numbers of Oriental White-rumped Vulture declined by 99.9 per cent between 1992 and 2007 on the transects surveyed each year during that period. The equivalent decline in the combined total of G. indicus and G. tenuirostris was 96.8 per cent. The population of Oriental White-rumped Vulture has an average annual rate of decline of 43.9 per cent between 2000-2007, whereas the combined average annual rate of decline of G. indicus and G. tenuirostris is over 16 per cent. A complete ban on the use of diclofenac in livestock and the establishment of conservation breeding centres are suggested to prevent the extinction of these three species of vultures.

In essence, this meant the numbers of White-rumped vultures were falling at the alarming rate of more than 40 per cent a year. From several lakhs in 1992, the White-rumped had, in 11 years, plummeted to about 11,000 birds. Equally worrisome were the cases of the Long-billed, whose population fell from about 15 lakh to 45,000, and the Slender-billed, which numbered about 33,000 and dropped to a mere 1,000 in 2009. The populations of the two species saw a crash of about 97 per cent. In 2007, there were believed to be about 200 breeding pairs of the White-rumped and the Slender-billed in the wild.

A nesting white-rumped vulture. The drooping neck is a typical sign of diclofenac poisioning.-MUNIR VIRANI

Chris Bowden, who heads the Asian Vulture Programme of the Royal Society for the Protection of Birds (RSPB), assumes, realistically, that dramatic declines have undoubtedly continued since then.

Though the discovery that vultures were dying at a catastrophic rate was realised first in Bharatpur, the reason for the deaths was discovered in Pakistan by a team of the United States-based Peregrine Fund. The team recovered more than 1,600 dead vultures from field sites in Pakistan and carried out post-mortem inspections on carcasses in good condition. The results showed that 85 per cent of the deaths were because of renal failure followed by visceral gout. The gout was identifiable by a white paste-like substance that clung to the internal organs.

Further scientific studies by the BNHS, the RSPB and the Zoological Society of London narrowed down the cause to the use of an anti-inflammatory veterinary drug called diclofenac. When a vulture ingested the carcass of an animal treated with diclofenac it had a disastrous effect on the viscera of the birds. Uric acid accumulated rapidly within tissues and on the surfaces of internal organs, causing visceral gout and rapid death from renal failure. Birds have been known to die within 72 hours of eating carcasses that had the remains of diclofenac.

In the laboratory at the Pinjore centre.-COURTESY: BOMBAY NATURAL HISTORY SOCIETY

The Slender-billed, the Long-billed and the White-rumped are voracious organ and muscle eaters unlike other vultures, which tend to eat tendons and other fleshy bits. Organs and muscles are the areas where drugs accumulate in the body and this explains why only these three Gyps species have been affected by diclofenac. Statistically, even if 1 per cent of the carcasses contain the drug the effect can be drastic on the vulture population. But the use of diclofenac was so widespread that it was present in 10 per cent of carcasses.

A campaign launched by the BNHS to ban the veterinary formulation of diclofenac led to the Union Ministry of Health and Family Welfare issuing a notification in May 2006 banning the production, sale and use of veterinary diclofenac and ordering a phasing out of the drug over a three-month period. Bowden believes the ban is generally fairly well implemented even though there was a recent contravention to this in Bihar. There is also a major loophole that is preventing the removal of diclofenac from the environment, and [this] urgently needs addressing.

A sub-adult white-rumped vulture feeding on a carcass.-SUVRASHIS SARKAR

The loophole, says Dr Vibhu Prakash, is that the human formulation of diclofenac is freely used by veterinarians despite there being at least eight other anti-inflammatory drug options for vets. To counter this, in 2008 it was made mandatory for the human formation of diclofenac to be marked as not for veterinary use. But, as Dr Nita Shah, who heads the vulture advocacy programme at the BNHS, said, this was a practice followed only by the mega pharmaceutical companies. The smaller companies do not bother with the marking.

Nita Shah said the BNHS and the Drug Controller General of India (DCGI) were working on a policy to prevent the use of the human formulation of diclofenac in animals. She said it was mainly the quack vets who used the drug. Explaining why the other options of anti-inflammatory drugs were not used by vets, she said: Essentially this is about demand and availability and budgets. The Animal Husbandry Department of every State has to order products by name. Right now there is a high demand for such medicine at the tehsil level, but this is not reflected in the States list of demands to the Drug Controller because the State is restricted by a quota.

She said that in districts that averaged around nine lakh livestock, the use of veterinary diclofenac used to average between 8,000 and 12,000 vials. These same areas now use about 3,000 vials of the human formulation on livestock. An ongoing study has shown that human diclofenac continues to be in the ecosystem, leaving vultures at risk. It also shows that reduced quantities of diclofenac were being used, indicating that vets were using the other recommended anti-inflammatory drugs as well.

With support from the Ministry of Environment and Forests, Nita Shah and her team are monitoring the use of painkillers in vulture landscapes in Madhya Pradesh, Gujarat and Rajasthan to see the extent to which diclofenac and other painkillers are being used. Once identified, the top three painkillers in use will be put through toxicity tests to study their impact on the environment. The ongoing study involves interacting with vets and chemists associations, understanding supply chains and looking at the flow of the human formulation of diclofenac. With the information that is being gathered, the BNHS will work with the DCGI to formulate a policy that prevents the use of the human formulation of diclofenac in animals.

A White-rumped vulture at the Rajabhatkhawa vulture conservation centre in West Bengal.-VIBHU PRAKASH

An interesting development in Shahs work is that she and the BNHS plan to involve the pharmaceutical industry in conservation work. Livestock and humans are the only groups that pharma companies test for, she said, referring to the processes prior to a new drug entering the market.

We are going to ask the Drug Controller to ask pharma companies to look beyond these two groups when they carry out their R&D, she said, emphasising that the idea was to make the pharmaceutical industry see its responsibility towards wildlife as well.

With the three endangered Gyps species continuing to decline by 12-40 per cent a year according to Bowden, there seemed little alternative to a captive breeding programme to stabilise the population. Three BNHS-run vulture rescue centres were set up, in Pinjore, Rajabhatkhawa, and Rani. The Pinjore centre is the most advanced, with three large colony aviaries. Rajabhatkhawa has two and Rani one. All the centres are run with the State government as a partner and are supported by the RSPB, the Zoological Society of London and the Darwin Initiative.

At the pinjore centre, a White-rumped chick.-VIBHU PRAKASH

Captive breeding involves trapping wild birds and rearing them in captivity. However, BNHS scientists have been accused of taking chicks from their nests and placing them in the vulture rescue centres. Nita Shah explained that chicks that grew up in captivity were more likely to breed in captivity because the surroundings would not be alien to them, unlike captured adults.

Though it offers a safe alternative to the poisoned surroundings, captive breeding is not a quick-fix solution. It is a slow process. Vultures are known to be difficult to breed and raise in captivity. They are monogamous and produce only one chick every year. The chick takes four years to attain sexual maturity. Even when fully grown, releasing the birds will be possible only if there is a poison-free landscape, said Nita Shah. Otherwise it will be dangerous and counterproductive to release them into the wild.

There were particular tensions about the breeding of the Slender-billed because of the birds rarity. So when two Slender-billed chicks were born last year, at Rajabhatkhawa and Pinjore, they signalled hope. BirdLife International, a global alliance of conservation organisations, describes the Slender-billed as a species rarer and more threatened than the tiger in India. Bowden said: Its known breeding population is largely confined to Assam now, with a very small number being seen regularly in Cambodia and Nepal. BirdLife estimates about 1,000 Slender-billed vultures in the wild with its population decreasing dramatically every year.

Owing to its rarity the Slender-billed is also the least known and least studied species of Gyps. The three centres have 280 birds and the breeding activity among all three critical species of Gyps vultures has vindicated the stand of those who promoted captive breeding as a means of conservation. Captive breeding takes on special significance in the light of the continuing use of the human formulation of diclofenac. If the vulture rescue centres had not been set up in 2006, it would be correct to assume that the birds would have been closer to extinction on the subcontinent than they now are.

Captive-bred Slender-billed nestlings that are about 100 days old.-VIBHU PRAKASH

The future is critically dependant on the captive breeding programme and a complete ban on vets using any formulation of diclofenac.

Bowden summed it up, saying: The breeding programme has managed to get over half the target of breeding stock envisaged, and breeding has begun for two of the three species so far. There is a long way to go, but releasing birds to a diclofenac- and poison-free environment is the realistic objective over the coming 10-15 years.

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