Vultures: What's Killing the Cleaners

That was in the vulture nesting season of 1996-97. Dr. Prakash had been studying the impact of contaminants, such as pesticides, on raptors in and around Keoladeo National Park (KNP). This wetland of international importance (under the Ramsar Convention on Wetlands) and World Heritage Site (under UNESCO's World Heritage Convention) is an enchanting waterfowl refuge, located about 180 km south of New Delhi, in Bharatpur town, Rajasthan state. Before the nesting season was over, Dr. Prakash had personally witnessed the same unusual mortality of white-backed vultures on five occasions and, by May 1997, 40 similar cases had been recorded. Some birds dropped dead from trees; a few remained on perches and nests, or suspended in branches; and even fledglings had been found dead in nests.

Word was sent around and soon it became evident that the phenomenon was neither restricted to just the KNP and its surroundings, nor to only a single raptor specie. Vulture populations over the whole country were crashing dramatically; and two species, the white-backed vulture Gyps bengalensis and long-billed vulture Gyps indicus were heading towards extinction. The BNHS sent out its first 'vulture alert' in November 1998. A second one followed in August 1999.

Although brought to the fore in 1997, the population decline seems to have started much earlier. In 1987-88, some 353 white-backeds' nests had been recorded in KNP. A decade later, in 1996-97, these had dropped by over 50 % to 150. Then they plummeted - 25 the following year, 20 the next and now there are none.

By 1998 it had also became apparent that populations not only of the white-backed but also the long-billed vulture were in rapid decline. That year, the maximum count of this Gyps species in KNP was 25, a 97 % reduction from a count of 816 birds in 1985-86. Since the end of the monsoon in September 1999, just a single long-billed vulture has been encountered in the Park.

Dr. Asad R. Rahmani, director, BNHS, who was in Abu Dhabi in January this year, recounts the shocking reports of vulture

Vultures near Dholkand, Rajaji National Park, in the northern Indian state of Uttar Pradesh... fast dying (click on the picture for a larger view)

disappearance that he is receiving from all parts of India. At one of the finest vulture areas (in the northern Indian state of Uttar Pradesh) where, till just a couple of years ago, vulture species were seen in thousands, as few as10-12 long-billeds and white-backeds have been noted in recent months. A researcher working in Pench National Park, Madhya Pradesh (central India) found dead vultures on waterholes during the summer of 1999; birds that appeared sick before they died. From southern India, an avid bird watcher wrote in to say that he had not spotted one long-billed vulture across south Karnataka since 1996, and his encounters with even the white-backeds had decreased. A carcass processing plant, 60 km away from Mumbai city, does not support a single vulture today; Dr. Rahmani had counted more than 300 at the site in 1988. Similar reports have come in from other parts of India - Gujarat (western India), Punjab (north), and Delhi.

Investigations are on to interpret the cause of decline. Food supply, it seems, is not a limiting factor. Plenty of carcasses are seen in KNP, but very few or no vultures have been observed feeding on them. Likewise, the loss of nesting and perching sites is ruled out because most of the large trees used by the species are still there; but unoccupied. Chemical pesticides and insecticides may be responsible for breeding failure due to organo-chlorine contamination in the tissue, but cannot account for large-scale adult vulture deaths. Deliberate carcass poisoning and calcium deficiency have also been considered and rejected.

A most plausible cause of the widespread mortality in adult and juvenile birds is a deadly viral disease.

Since first reports of the vulture die off in KNP came in, the BNHS and U.S. Fish and Wildlife Service Office of International Affairs have been closely monitoring the situation. Birds that become sick and die are being sent for autopsy and tissue samples to whatever laboratory in the world capable of identifying the disease. Autopsies conducted on a few revealed their livers and internal organs coated with whitish crystals assumed to be uric acid, deposits of which cause gout in humans. In KNP, captive vultures are being housed in a specially constructed facility for observation; and the BNHS is establishing an Indian Vulture Study Group.

It is feared that that the extinction process under way with the two vulture species may also be affecting other Gyps vultures found

Bad news... a mysterious disease is killing vultures

in India - Himalayan griffon Gyps himalayensis and Indian griffon Gyps Fulvus - besides eventually spreading to the Gyps species of the Middle East, Europe and Africa.

What are the ecological implications of vulture extinction? "They are manifold," says Dr. Rahmani. " First of all, vultures are an integral part of the ecological system as they help in cleaning up the carcasses of large mammals. Without this, chances of diseases spreading are high in rural areas. Secondly, the absence of vultures has resulted in an increase in numbers of stray dogs and crows (because of less competition for food from vultures). This will put more pressure on other birds and small mammals because stray dogs and crows also prey upon birds and small mammals. Wherever crows increase, as in Bombay, small songbirds decrease due to heavy crow predation on eggs and chicks. We suspect that the dog population is also increasing but no data is available. I have seen that large numbers of dogs prevent the remaining few vultures from eating carcasses. Earlier, when vultures were present in huge numbers, by their sheer numbers they would prevent dogs coming to a carcass; but now the case is quite the opposite."

In the prevailing circumstances, any Gyps vultures in captivity and apparently healthy should be considered invaluable.

WILDLIFE - DOING WELL IN CAPTIVITY; NOT SO IN THE WILDERNESS The year 2000 brought heartening news for rare and endangered wildlife species under protection in the UAE. Dubai Zoo's millenium baby was a male pygmy hippopotamus, the first male hippo at the zoo. Another breeding success followed - that of the African spoonbill. Dubai Zoo now has 10 of these spoonbills residing together with 11 other species of rare bird in a single enclosure. Next, Sharjah's Breeding Centre for Endangered Arabian Wildlife announced the birth of two Arabian leopard cubs, the third successful litter in two years. Happy news indeed, because the animal is highly endangered in its natural habitat. Meanwhile, efforts to save the Arabian oryx continue, with the UAE, which holds the largest captive population (over 1000) of the endangered species in its range countries, now poised to house the secretariat of the international Coordinating Committee for Conservation of Arabian Oryx. There are some 500 oryx on Sir Bani Yas Island (Abu Dhabi) itself, with the remainder in private groups on other islands and the mainland, including Al Ain Zoo. But while wildlife protection policies are being reviewed, management plans for the conservation of endangered species are being drawn up, and research on their reproduction is ongoing, out in the wild animals are dying. In February this year came the disturbing report that 'the last known' Arabian wolf and some Arabian tahrs had been killed in Ras Al Khaimah, apparently shot by hunters. Before this, 10 caracals had been slaughtered. Again, in Ras Al Khaimah, fishermen are still using banned nylon nets to the detriment of marine life because large quantities of non-targeted fish species get caught and also destroy corals. Further disquieting news followed - marauding feral cats are devastating colonies of birds breeding on Abu Dhabi's offshore islands. Among the vulnerable bird species is the ground-nesting red-billed tropicbird, while development on islands is threatening the socotra cormorant, which is endemic to the Gulf region. PLASTIC NUISANCE IN NEPAL CITIES Nepal is all set to ban the use of plastic carrier bags because huge quantities of discarded plastic are littering the cities, clogging drains and polluting cultivated lands. Besides, incineration of plastic releases toxic fumes into the atmosphere posing a health hazard to the public and, more so, to workers in plastic units. Of all the garbage that accumulates in a Nepalese city, more that 5 per cent comprises plastic bags, most made up of such thin plastic material that they are uneconomical to recycle. Rather than pass an order increasing the thickness of plastic bags in use, the Nepal ministry of environment is inclined to ban them all together, irrespective of size, shape and colour. Environmentalists are delighted at the prospect of the return of jute, cloth and paper bags in place of plastic.

WHAT ON EARTH CAN WE DO? Adhere to the rules in Protected Areas (Wildlife Sanctuaries). Dubai Municipality's rules prohibit, particularly the following: Hunting, transporting, killing or disturbing marine or wildlife or carrying out any work which may destroy them. Hunting, removing or transporting any creature or organic materials such as mollusks, coral reefs, rocks or sand for any purpose. Destroying or transporting plants from protected areas. Damaging or disfiguring geological or geographical formations of the habitat or breeding place of flora, fauna and birds. Introducing non-indigenous species to the protected areas. Polluting the land, water, or atmosphere of the protected area by any means. Constructing buildings, structures, roads or use motorised vehicles, or undertake any agricultural, industrial or trade activities in the conservation area…or areas surrounding it, unless by a permit from the competent authority.

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