Thursday, February 13, 2014

Orangutans in Borneo Spending More Time on the Forest Floor

As the world's largest arboreal mammal, orangutans quite logically spend much of their time in trees. But new research on Bornean orangutans reveals that the great apes spend more time on the forest floor than previously believed.

Mark Harrison of the Orangutan Tropical Peatland Project, and his international team of collaborators spent seven years tracking the movements of Bornean orangutans with 1,409 camera traps across 16 sites in the Borneo jungle.

Their project, which took place between June 2006 and March 2013, detailed the movements of 641 individual orangutans over nearly 160,000 days.

Prior to this study, the researchers report that evidence of orangutans coming down from the trees was rare and was usually associated with habitat disturbance.

"We've known for some time that orangutans use the ground to travel and search for food, but the influence of anthropogenic disturbances in driving this behavior has been unclear. This is crucial to understand in this age of rampant forest loss and fragmentation, which is slicing up the orangutan's jungle home," Harrison said.

"We found that although the degree of forest disturbance and canopy gap size influenced terrestriality, orangutans were recorded on the ground as often in heavily degraded habitats as in primary forests," Harrison continued.