Wild gibbons are severely threatened by habitat loss

Wild gibbons are some of the most endangered primates on Earth, which is primarily due to habitat loss. A new study suggests that gibbons in southern Borneo are even more vulnerable to habitat loss than what was previously realized. 

The research, led by Dr. Susan Cheyne at the Borneo Nature Foundation, has revealed that wild gibbons living in the peat swamps of Borneo require between 20 and 50 hectares of forest territory for each group.

While it is known that the natural habitats of gibbons are threatened by deforestation and wildfires, relatively little has been studied about the size of their territories or how they use certain spaces for feeding and social activities. 

The researchers monitored four groups of wild Bornean southern gibbons in the Sebangau National Park between 2010 and 2018. The team tracked the GPS location of each group, and recorded observations of the creatures at five-minute intervals from dawn till dusk.

The experts determined that the Gibbons’ territory spanned somewhere between 21 and 52 hectares, including where they sleep, socialize, and sing “duets” together with their mates. The apes were also found to forage over a larger home range of up to 148 hectares that they share with neighboring groups.

For three of the groups, the territories remained approximately the same throughout the nine-year study period. The other group, however, was forced to shift their range west when part of their habitat was damaged by forest fires in 2015.

The gibbons are highly territorial, and this behavior combined with the vast size of their ranges will make these animals extremely vulnerable to future habitat loss. They could ultimately be confined to areas of forest that are too small to accommodate multiple competing groups.

“Gibbons show high site fidelity for specific areas of forest and maintain these territories over many years. Understanding how Gibbons use the forest is critical to their conservation,” said Dr. Cheyne. “These data can feed into creating protected areas of suitable size and habitat quality to maintain viable populations of the singing, swinging small apes.”

The study is published in the journal PLOS ONE.

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By Chrissy Sexton, Earth.com Staff Writer

Image Credit: Borneo Nature Foundation