It is a suitably primal noise for one of the world’s last surviving ancient wildernesses. To reach Betung Kerihun in central Borneo takes four hours by motorised canoe from the nearest settlement.

The forest is an almost untouched Eden. Orang-utans and gibbons live high in the canopy. On the forest floor clouded leopards and eight-metre pythons hunt wild boar and deer and are themselves hunted by one of the last truly nomadic forest peoples, the Penan. But this rainforest, which has survived for millions of years, may now be doomed.

A £4.2 billion plan proposed by a Chinese bank and backed by Jakarta politicians would clear 1.8 million hectares of this wilderness over the next six years to grow oil palms to feed the world’s growing appetite for margarine, ice-cream, biscuits and biodiesel fuel.

Until now Betung Kerihun, technically a protected national park, has been saved by its remoteness despite the network of roads that illegal loggers have begun to push inside its boundaries.

What survives is a biological treasure that staggers scientists newly arrived from Europe. It is home to thousands of tree frogs, bats and orchids. More than 1,000 insects have been identified in a single tree. In one ten-year period 361 new plant, animal and insect species were discovered in Borneo.

Charles Darwin, who explored the giant island before writing The Origin of Species, called it “one great untidy luxuriant hothouse made by nature for herself”.

Reaching the virgin jungle from the coast takes days by river or logging road across a landscape of tree stumps, and the most common sound is that of the chainsaw. Only half of the island is now covered with forest, compared with three quarters in the 1980s.

Conservationists believe that the real motive for the oil palm scheme is to gain access to the valuable timber along a great swath of the Indonesian-Malaysian border.

“It’s a scam,” said Stuart Chapman, of the WWF conservation group. “Palm oil is a lowland equatorial crop and not suited to steep upland soils. There are two million hectares of idle land, already cleared of forest, in lowland Borneo which is suitable for planting. But putting this plantation in the island’s centre would give logging interests the excuse they need to cut down trees.”

Conservationists say that the plantation would strip trees from Borneo’s watershed, where 14 of the island’s 20 rivers rise. It threatens ecological disaster and continual flooding in settled areas. Haze — choking smoke from forest fires — would drift across Singapore and Malaysia’s cities as it has done regularly since the late 1990s.

The plan, with finance from the China Development Bank, has powerful and enthusiastic backers. Big businessmen in Jakarta and the Economy and Agriculture ministries say that it would generate 500,000 jobs in an economically backward area.

Anton Apriyantono, the Indonesian Agriculture Minister, told The Jakarta Post: “This project will reduce the prosperity gap between our people living along the border and those in Malaysia. The end product can be exported overseas or sold on the local market for developing biodiesel fuel, which is much needed to help to reduce domestic consumption of gasoline. Therefore the plantation has huge prospects.”

Jimmy Syah, a WWF field worker, believes that there is a 50 per cent chance of the plantation going ahead.

“Enjoy the experience,” he said, halfway up a jungle-covered hillside. “The forest may not be here in ten years.”

WWF is urging the governments of Indonesia, Malaysia and Brunei to create a 22 million-hectare protected area called the Heart of Borneo. It will lobby for the scheme at next month’s Conference of Biological Diversity in Brazil.

The alternative, it argues, is a repeat of what happened in another part of Indonesia. Conservationists cautioned in the 1980s that Sumatra would lose all its rainforest unless steps were taken to protect it. Now nearly all has vanished.

In the longhouses of Borneo, the giant communal homes on stilts where up to 50 families of the indigenous Dayak people live together, the proposals have brought conflict.

Some want the televisionss and karaoke machines that they could buy with palm oil jobs. Others want to keep their ancestral forests.

Pius Ongyang, a 67-year-old leader of the Tumugung tribe, is an opponent. He has seen many changes in a long life, including the coming of Christianity and the end of slavery, head-hunting and human sacrifice in the 1950s. He does not want to see the arrival of oil palm.

“It has happened in other parts of Borneo,” he said. “The profit only goes to the Government and to big companies. There will be floods if the trees go, and where will we hunt and get our building materials?

“The people are divided over this, perhaps 50-50. If oil palm comes, we will see real conflict. Perhaps we will see the end of the life we know.”

PALM OIL BOOM

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