For several decades they have been among the world’s rarest birds, with tens of thousands of pounds spent on breeding programmes and round-the-clock guarding in a special protected zone.

But conservationists believe that the Bali Starling has become extinct in the wild.

The Indonesian Government, sensitive to international criticism, insists that there are still two flying free in Bali Barat National Park at the island’s western end.

With their beautiful snowy-white plumage and lavish crest of white feathers, they have made popular cage and aviary birds — so popular that bird hunters are believed to have wiped them out in the wild.

Sukianto Lusli, Executive Director of BirdLife Indonesia, said: "This is such a beautiful bird. Its charm made it extinct. Everybody wants one in his cage at home."

The starling was once abundant on Bali, breeding in coconut groves. Trapping for the caged bird market in Europe and North America in the 1960s caused a massive population decline to only 14 wild birds by 1991. The population hovered at about a dozen for the rest of the decade as frantic but unsuccessful efforts were made to return numbers to the minimum viable population of 500.

Birds are a national obsession in Indonesia and no home is complete without a caged song bird, the more exotic-looking the better. Fears over bird flu have spurred many families to open their cage doors in recent months to give their pets an unexpected taste of freedom.

Small armies of bird catchers using nets or birdlime trawl the islands of the archipelago snaring finches, larks and warblers to be sold in huge sprawling bird markets such as Jalan Pramuka, in Jakarta.

Migrating waterbirds from Siberia and China are trapped in their thousands in the marshes of Java to be fried and sold as roadside snacks.

Conservationists say that trapping wild birds for sale is a bigger threat than habitat loss to Indonesia’s 1,539 species, 17 per cent of all the birds recorded on the planet.

The business generates millions of dollars in revenue annually, rivalling even the illegal logging trade for profitability.

Rare parrots, hornbills and cockatoos are especially sought after. Jakarta’s rich pay high prices for them as pets. The birds are also smuggled abroad in an illegal export trade focused on the Netherlands and Germany. Many more die struggling in nets or in transit to markets.

Several of Indonesia’s most spectacular species are threatened, including the magnificent yellow-crested cockatoo, seram cockatoo, and goffin cockatoo. So far none has become extinct.

Bali starlings are now bought for several thousand pounds each by Indonesians who are not deterred by the unlikely possibility of a five-year prison sentence for owning one.

BirdLife International believes that it may be possible to restock the island with the birds through a controversial breeding programme. But to stop them being immediately poached it would also be necessary to reduce their rarity value by flooding Indonesia’s bird markets with captive-bred Bali starlings.

Mr Lusli said: "It could be done. We think there are about 500 captive birds in Indonesia and if there was an amnesty where people could hand them in, they could become stock for a massive captive breeding programme. We would also ask for the return of caged birds held abroad.

"But we must admit that it is extinct in the wild and start thinking of a radical way to rebuild its population on Bali."

He said that corruption would also have to be countered. On Bali, poachers are believed to have paid bribes to officials to allow them to hunt birds, and corruption lubricates the workings of the bird trade everywhere.

In the Indonesian part of New Guinea, famous for its multicoloured birds of paradise, the military is said to be heavily involved.

Mr Lusli said: "When a navy ship comes back from Papua with an army detachment returning from a tour of duty it is full of birds and animals — like a floating zoo. We have to stop that kind of thing."

AT RISK

• Amsterdam Island albatross Nests only in French Antarctic. 80 known birds, 17 nesting pairs
• Slender-billed curlew No nests found since early 1900s. Last confirmed sighting in Northumberland several years ago
• Californian condor Last remaining wild example captured in 1987. Now around 100 in captivity
• Hawaiian crow Critically endangered by disease. None in the wild
• Amami Thrush Japanese native threatened by deforestation. Only 60 birds left in the world
• The last Bali starlings flying free were probably bred in captivity

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