Fires in Indonesian Borneo leave critically endangered orangutans with nowhere to flee

Wildfires driven by an unusually strong El Niño climate pattern have torn through forests in Indonesia's West Kalimantan province, cutting off escape routes for the critically endangered Bornean orangutan (Pongo pygmaeus).

Fires have burned roughly 9,055 hectares (22,000 acres) in and around Gunung Palung National Park, home to an estimated 2,500 orangutans and one of the world's longest-running wild-orangutan research sites, according to Indonesia's Ministry of Forestry. Flames have come within about 200 meters of a satellite research station, prompting more than 40 staff and volunteers to dig firebreaks and rig makeshift sprinklers to soak the surrounding peat.

In the nearby Mendawak Biodiversity Corridor, which conservation group Sangga Bumi Lestari estimates holds one of the largest orangutan populations outside any protected area, fires had burned nearly half of one key forest tract by mid-September.

An adult male orangutan named Sempurna died Aug. 30 after being found struggling to breathe near an oil-palm plantation; a necropsy pointed to smoke-related lung damage. As of Sept. 16, rescuers had pulled 21 orangutans from the fire zone.

"Orangutans are fleeing from these forests. It's just horrible," said Cheryl Knott, a Boston University biological anthropologist who has studied the park's orangutans for 32 years.

Conservationists say drained peatland, dried out by past forest clearing, is intensifying the blazes and warn the fires could persist as El Niño conditions continue into 2027.

This brief is based on reporting by Hans Nicholas Jong, published Sept. 23, 2026, on Mongabay. Read the original: https://news.mongabay.com/2026/09/as-fires-spread-in-indonesia-bornean-orangutans-run-out-of-forest-to-flee/