Conservationists hope the vulture chick will be the first of many

The bird belongs to one of three species of Asian vulture that are listed as critically endangered.

Populations in the wild have crashed because they eat carcasses containing traces of the drug diclofenac.

The use of the anti-inflammatory drug in the region is being phased out but it could take 10 years, scientists say.

Dr Vibhu Prakash, principal scientist for the vulture breeding programme, said: "This is the most precious new year gift from nature to vulture conservation."

The egg was laid in November and the centre's staff had been waiting and hoping ever since, he added.

"This success shows that we have got the conditions right, so we can plan ahead with confidence."

Soaring death toll

We have to measure all of our successes against the backdrop that we are still talking about the extinction of the vultures

Nick Lindsay,

Zoological Society of London

Nick Lindsay, ZSL's head of international zoo programmes, said the society had been heavily involved in the centre since the late 1990s.

"It was established with a UK government Darwin Initiative grant, when the cause of the decline in vultures was still being investigated," he said.

The centre shifted its focus from research to breeding once it was discovered that diclofenac, a drug widely used by vets in the region to treat cattle, was the main reason for the vultures' deaths.

The link was firmly established in 2004 when tests on captive vultures fed carcass flesh traced with the drug produced symptoms that were strikingly similar to those witnessed in sick birds in the wild.

Mr Lindsay said the centre's work concentrated on the three species most seriously affected by diclofenac: the oriental white-backed vulture (Gyps bengalensis), the long-billed vulture (Gyps indicus) and the slender-billed vulture (Gyps tenuirostris).

In the past 15 years, population losses of more than 95% have been reported in these birds.

'Worrying scenario'

Although India, Pakistan and Nepal were taking steps to phase out the use of the drug, Mr Lindsay said the birds' battle for survival was far from over.

Vultures used to be a more common sight in the skies

"The communities that use this drug can be remote; cattle are literally found in their millions and people care very much for their well-being, so the drug is still being widely used because it is a very effective treatment for the cattle.

"If you take all those different factors, it creates quite a worrying scenario."

But he added that there were some projects on the ground that were helping to take the drug out of circulation.

In Nepal, conservation groups were visiting pharmacies and clinics located within areas used by vultures and swapping supplies of diclofenac with a bird-friendly replacement, meloxicam.

"This sort of thing might be possible in Nepal because it is a much smaller country than India and the problem is not as extensive," he suggested.

"But even then it is going to be a struggle because the range of these birds is so vast."