Experts: Orang Utan decline began 2,000 years ago

KOTA KINABALU: The decline in Borneo’s orang utan population is not just due to recent deforestation but a phenomenon that could have started over 2,000 years ago, a research found.

A scientific paper published in the PLOS ONE journal by a team of experts found that the Borneo orang utan began experiencing a major demographic decline between 200 and 2,000 years ago based on samples collected in six different sites in Sabah and Kalimantan.

This was the main conclusion by the team, which comprised scientists from the Instituto Gulbenkian de Cincia (IGC) in Portugal, the Anthropological Institute and Museum of the University of Zurich in Switzerland, the CNRS in France, Cardiff University in Britain and the Danau Girang Field Centre in Sabah.

“The recent loss of habitat and its dramatic fragmentation have affected the patterns of genetic variability and differentiation among the remaining populations of orang utan and increased the extinction risk of the most isolated ones,” said Dr Reeta Sharma, who is from IGC, the lead author of the paper.

“We used orang utan samples collected in six different study sites in Sabah (Kinabatangan and Danum Valley) and Kalimantan, and genetic markers to identify signals of population decline,” said Dr Sharma.

Dr Benoit Goossens, who is Danau Girang director and a co-author, said the dating of the decline varied across sites but was always within the 200 and 2,000-year period.

“This suggests that in some sites at least, orang utan populations were affected by demographic events (like climate change and arrival of modern humans) that started much before the recent human impact on environment in Borneo,” he added.

The recent finding complemented those published in 2006 on the Kinabatangan population and underscored the need to expand conservation measures suggested under the Orang Utan Action Plan.

This included the protection of private lands to connect the existing protected forest lots, the establishment of corridors, wildlife monitoring and law enforcement, added Dr Goossens.

Source: The Star