Indonesia fires threatens critically-endangered orangutan: IUCN

Wildfires that tore through Indonesian Borneo's vast tropical forests have piled pressure on critically endangered Bornean orangutans, the International Union for Conservation of Nature (IUCN) said Saturday.

Indonesia has been battling fires for weeks in parts of Borneo and Sumatra, sending suffocating haze across the islands and neighbouring Malaysia and Singapore.

Fires are currently burning within habitats containing 52 percent of Borneo's orangutan population, including 13 of the 20 largest remaining populations, it said.

"Fire and smoke exposure impose measurable physiological, behavioural and ecological costs on orangutans in peat forest habitats," the conservation network said.

During haze, orangutans show signs of fat breakdown despite eating more and resting more, suggesting elevated energy demands likely from an immune system forced to work harder, it said.

Wildfires have also been reported in the habitats of five gibbon species across Sumatra and Borneo, the conservation network said.

"Gibbons breathe the same smoke-laden air as the people living alongside them, and there is every reason to expect they suffer similar respiratory harm, on top of habitat loss and disruption to the behaviours that keep wild populations viable."

As of Tuesday, Indonesia had rescued 100 animals, including 53 orangutans, that were threatened by the blazes, a forestry ministry spokesman said.

Conservationists call on the authorities to go beyond first response and implement prevention measures.

"Emergency response must be followed by sustained investment in preventing future fires," Ronna Saab of Forum Konservasi Orangutan Indonesia (FORINA) said in a statement. 

Those measures include "protecting and rewetting peatlands, addressing drainage and deforestation, and ensuring burned forests are protected from subsequent conversion and appropriately restored," Ronna said.

The Indonesian government said more than 202,000 hectares of land were burnt countrywide between January and July, the latest available data.

The Nusantara Atlas project has put the number at closer to 900,000 hectares between January and August.