Hans Nicholas Jong, Jakarta – Fires have burned part of a decade-long orangutan habitat restoration site in Indonesian Borneo, raising fears among conservationists that another severe fire season could wipe out years of recovery efforts before the dry season has even fully begun.
A decade ago, Yayasan IAR Indonesia (YIARI), the Indonesian affiliate of International Animal Rescue, began restoring degraded orangutan habitat in Pematang Gadung village in Ketapang district, West Kalimantan province, after villagers repeatedly reported orangutans (Pongo pygmaeus) entering farms and eating crops.
The incursions were driven by habitat loss. Large parts of the surrounding forest had already been degraded, including during Indonesia's catastrophic 2015 fire season, when more than 1,500 hectares (3,700 acres) of land in and around the village were burned.
Since then, YIARI, together with the government and local communities, have worked to restore the damaged landscape by planting trees that provide food for orangutans, with the hope that if enough food is available in the forest, the critically endangered apes will stop venturing into farmland.
As of early 2026, the group had restored around 300 hectares (740 acres) with 150,000 trees, including fruit-bearing species favored by orangutans.
The work is especially important because the remaining orangutan habitat in the area has become increasingly fragmented. Illegal gold mining operations now surround much of the forest, leaving wildlife confined to shrinking patches of habitat.
"Once the entire area is restored with fruit-bearing trees, we expect it to support more orangutans and allow the population to spread out," YIARI CEO Karmele Llano Sanchez told Mongabay.
In 2024, camera traps finally recorded orangutans returning to the restoration site, a milestone conservationists saw as evidence that the recovering forest was beginning to function again.
"Along the riverbanks we've started to see orangutans, especially in certain seasons," said Rohadi, a 40-year-old resident of Pematang Gadung, who has worked on forest patrols and restoration efforts since 2015.
"Usually around June, during fruiting season, when trees along the river have matured. When traveling by boat, we sometimes also see birds and wild boar. So wildlife is starting to return."
But in early March, fires linked to nearby land clearing spread into the restoration area.
A spatial analysis by forest-mapping initiative TheTreeMap, requested by Mongabay, found that the fires burned at least 171 hectares (423 acres) of forest in the village.
Rohadi said he was devastated watching flames enter the area that residents and conservationists had spent years trying to restore.
"I felt like crying because what we built over several years was destroyed in just one month," he said.
Fire jumping across rivers
The fires burned for nearly a month, briefly subsiding only when rain fell in mid-March, before flaring up again toward the end of the month, according to Rohadi.
The fire initially started in an area being cleared for oil palm planting across a river from the restoration site.
But embers carried by strong winds jumped the water and ignited dry vegetation inside the recovering forest.
"Even though the river is 15-20 meters [49-66 feet] wide, the fire still jumped across," Rohadi said.
Parts of the restoration area remain covered with ferns, shrubs and other flammable undergrowth growing between planted trees, making the landscape highly vulnerable during dry conditions.
"Just one person clearing land for oil palm – across the river, about 2 kilometers [1.2 miles] away – was enough to trigger a fire that spread quickly and reached our restoration area," Sanchez said.
The incident highlights a larger problem unfolding across Indonesia's fire-prone peat landscapes.
Analysis by environmental NGO Madani Berkelanjutan found that 67,450 hectares (nearly 167,000 acres) of land were suspected to have burned across Indonesia between January and March this year, even though much of the country was still technically in the rainy season.
More than 65% of the burned area was peatland, according to the analysis.
That matters because degraded peat dries out easily and becomes highly flammable. Once drained or damaged, peat loses its natural ability to retain water, allowing fires to spread rapidly both above- and belowground, often reigniting even after rain.
The problem is particularly acute in degraded landscapes dominated by ferns and scrub vegetation, like parts of the restoration site in Pematang Gadung.
"That makes us very concerned, because this isn't even the peak of El Nino yet, but it's already extremely dry here," Sanchez said.
"There has been some localized rain, but it's not enough to properly moisten fire-prone land."Firefighters extinguishing fires in the Pematang Gadung village, Ketapang district, West Kalimantan, in March 2026. Image courtesy of YIARI.
Fear of another 2015
Scientists and government forecasters have warned that El Nino conditions could develop later this year, increasing the risk of prolonged drought and another severe fire season across Indonesia.
Some global forecasts suggest this year's El Nino could become one of the strongest in at least a decade, although significant uncertainty remains over how intense it will ultimately be.
For Sanchez, the situation evokes memories of 2015, one of the worst fire disasters in Indonesian history, when 2.6 million hectares (6.4 million acres) of forest and peatland across the country went up in flames.
"We were very unprepared," she said. "We experienced extremely brutal conditions – the forest was devastated, and the number of orangutan rescues increased drastically during 2015-2016."
YIARI rescued more than 80 orangutans during and after the fires, many of them stranded in burned forests with little food left.
"We found many orangutans that were emaciated after months of hardship," Sanchez said.
Research has shown that prolonged fires severely reduce food availability for orangutans, forcing the apes into starvation conditions, while smoke exposure weakens their immune systems and damages their health.
Known as gardeners of the forest because they help spread seeds around, the Bornean orangutan is listed as critically endangered. Its populations are estimated to have declined by more than 80% over the past several decades due to habitat loss from deforestation, mining, plantations and fires.
"This time, we want to be truly prepared," Sanchez said.
Racing against time
Since the 2015 fires, YIARI has invested in firefighting equipment and training, including pumps, patrol teams and integrated fire management systems.
But Sanchez said the organization still isn't fully prepared for a prolonged drought or a major El Nino year.
"If it were a normal dry season, we would be ready," she said. "But we are not yet ready for a severe one."
One major challenge is access to water.
Portable pumps are needed because fires often burn far from rivers, but the equipment is expensive. A single portable pump can cost around 300 million rupiah ($17,300), not including hoses and other infrastructure.
YIARI is also trying to build observation towers, expand patrol capacity and acquire drones to monitor areas that are inaccessible by road.
The organization estimates it needs around $250,000 to strengthen its fire preparedness this year.
Right now, Sanchez said, the group is racing against time before the dry season intensifies.
"If we wait until fires happen, we won't have time to raise funds, find donors, procure equipment, or recruit staff, because by then we'll already be in the dry season," she said.
Indonesia's environment minister, Mohammad Jumhur Hidayat, recently said fire mitigation efforts must be intensified ahead of the expected dry season, including improving water management in concession areas and supporting fire prevention in community-managed landscapes.
But civil society groups say weak law enforcement against companies that either set or allow fires in their concessions remains one of the biggest unresolved problems behind recurring fires.
For Rohadi, however, the threat feels much more immediate.
After years spent replanting trees and watching wildlife slowly return to the recovering forest, he said he fears another major fire season could erase everything again.
"We can't imagine losing everything and going back to zero," Sanchez said. "That would be devastating."