Wildfires threaten Borneo's rare primates and critical peatland habitats

Peatland fires ignited by an El Niño-related dry spell have ravaged Kalimantan's rainforests since early August, producing toxic haze across Indonesia. In Sebangau National Park, home to up to 9,000 critically endangered Bornean orangutans, a blaze crossed the park boundary in early September but was largely contained to open peat and sedge areas. Dr. Susan Cheyne of the Borneo Nature Foundation says protecting the forest is essential for safeguarding every orangutan and the park's rare primates, including the largest population of Bornean white-bearded gibbons.

Smoke has reduced gibbon song frequency and shortened their calls, a pattern also observed in orangutans, while ground-dwelling primates face food shortages in fragmented patches. Decades-old illegal canals have dried the peat, turning it into a tinderbox that fuels underground “zombie” fires. The foundation has responded by constructing more than 1,000 drainage dams, planting almost a million trees, and supporting up to eight fire teams, each costing about $100 per day. Nevertheless, rains are not expected until late October or November, leaving the wildlife vulnerable.