"The 20-year scenario is rather alarmist and not realistic. The lifespan of one orang-utan is 20 years and there are babies born every year," said Geoffrey Davison, the Malaysian Borneo program director for WWF.

The British chapter of the World Wide Fund for Nature (WWF-UK) said in a statement that 91 percent of the orang-utan population in Borneo and Sumatra islands had disappeared over the past century.

The red-haired apes, close kin to humans, are found only on Borneo, which is shared by Malaysia, Indonesia and Brunei, and on the neighbouring Indonesian island of Sumatra.

"There are now fewer than 30,000 orang-utans left and it is likely that they will become extinct in the wild in as little as 20 years time if this decline continues," the WWF-UK statement said.

It blamed commercial logging, clearance for oil palm plantations and agriculture, hunting and poaching for the bush meat and pet trades as well as forest fires for the shrinking population.

The statement echoed concerns voiced by Harvard University researcher Cheryl Knott, who wrote in the October issue of National Geographic magazine that orang-utans could disappear within the next 10 to 20 years if the illegal logging that is destroying their habitat is not stopped.

But Davison told AFP that the 20-year forecast was unrealistic because it failed to take into account local conditions and ongoing conservation projects.

For instance, he said, hunting and poaching were not a problem in Malaysia's Sabah state, which is home to some 13,000 of the apes.

"Over the next 20 years, the population will face real challenges and there is no doubt that there will be some local spots in which orang-utans will disappear but there will still be orang-utans in Sabah and Borneo in 20 years."

However, he agreed that it was necessary to increase conservation efforts given the long-term decline in the population due to the depletion of forests.

The WWF-UK said only 33 percent of the Sabah orang-utan population were found in protected areas such as parks or wildlife sanctuaries, leaving the rest vulnerable.

It noted that orang-utans have the slowest reproductive cycle of all the great apes, with an average of eight years between births.

The WWF-UK statement coincides with a two-week television program hosted by actor Brian Capron to raise awareness of the plight of the orang-utans.

TERRA.WIRE