SARAWAK’s population of Bornean orangutans has stabilised at roughly 2,000 individuals, a milestone officials credit to decades of habitat protection and coordinated conservation with NGOs, scientists, communities and industry.
Since 1983, the state has gazetted large swathes of primary and secondary forest as Totally Protected Areas (TPAs), now spanning more than 230,000 hectares. The network includes Lanjak-Entimau Wildlife Sanctuary, the state’s largest orangutan refuge, and Batang Ai National Park, which was extended by 2,119 hectares in 2024. About 95 per cent of Sarawak’s wild orangutans are concentrated across Lanjak-Entimau and Batang Ai.
The chief executive officer (CEO) of Sarawak Forestry Corporation (SFC), Abang Arabi Abang Aimran, says improved monitoring and research have underpinned the gains.
“Over the years, among others, SFC has carried out research projects through the RIMBA initiative with the Smithsonian, using camera traps to monitor orangutan movements and behaviour,” said Abang Arabi.
Conservationists emphasise the species’ wider value. As an “umbrella species,” protecting orangutan habitat safeguards many other forest-dependent animals and the ecosystems local people rely on.
Officials caution that the work is unfinished. Development pressures, particularly rural road links near TPAs, must be carefully planned to maintain the hard-won stability of Sarawak’s rare northwest subspecies, Pongo pygmaeus pygmaeus.
259 orangutan nests beyond parks
Fresh field surveys led by WWF-Malaysia, in collaboration with communities in Ulu Sungai Menyang, have mapped orangutans living outside protected parks, evidence that planning must extend beyond TPA boundaries.
WWF-Malaysia’s Head of Conservation, Cynthia Chin, said Sarawak’s terrestrial mammals team ran two phases of surveys, August–October 2024 and April–June 2025, recording orangutan nests in repeated rounds to estimate presence and persistence.
“Each phase of the survey included three rounds.Each survey phase took 42 days to complete. To date, the team marked and counted a total of 259 orangutan nests,” she said.
Researchers also both sighted orangutans and heard long calls during the work.
“Strong signs that these great apes still inhabit the area, which is outside the Transboundary Protected Area (TPA).
“Each nest counted gives us vital information about how many orangutans remain and where they are – We will be sharing the data with our stakeholders – so that they can make informed and sound decisions when proposing development projects for the people,” Chin said.
SFC says such findings align with years of TPA-level monitoring and complement earlier landscape-wide nest counts that identified important conservation areas south of Batang Ai.
The message for planners is clear: orangutans’ use of forest mosaics outside park lines means roads and other infrastructure must be sited with current biological data in hand.
Iban stewardship sustains red ape forests
Community knowledge and culture are proving pivotal to orangutan protection in Sarawak, where Iban longhouse communities act as guides, field assistants and stewards across landscapes they share with the critically endangered great ape.
SFC says Iban experience, navigating terrain, reading signs and knowing fruiting cycles, “contributed tremendously” to orangutan surveys and conservation.
In these landscapes, a widely held taboo regards orangutans as ancestral spirits, strengthening local ownership and discouraging harm.
The private sector has also helped. For roughly three decades, Borneo Adventure has worked with Indigenous and local communities to build responsible eco-tourism around Batang Ai, creating incentives to keep forests standing.
Furthermore, Abang Arabi said orangutan fieldwork is formidable; teams spend weeks in remote forests scanning the canopy for nests, so strong local partnerships are essential.
“Researchers and their field assistants often spend weeks at a time deep in the forests, looking up at the trees trying to spot orangutan nests,” said Abang Arabi.
Long-term ecological notes, such as SFC’s documentation of 89 orangutan-eaten fruit tree species in Batang Ai, complement cultural knowledge and help managers plan safeguards for fruiting seasons and low-impact visitor activities.
Balancing roads and orangutan conservation
As Sarawak expands rural connectivity, conservationists warn that new roads threading forest margins can intersect orangutan ranges, and that the apes do not “recognise” park lines.
“Orangutans do not recognise boundaries between TPAs and non-TPAs.Rural roads are coming in and are cutting across the landscapes where orangutans are spotted in Batang Ai, Gunung Lesong and Ulu Sebuyau,” Abang Arabi said, calling for careful route selection and mitigation.
The state says it is possible to strike a balance between development and conservation, but that will require using up-to-date biodiversity data to shape alignments, buffers and construction timing.
Meanwhile, Chin said her team will share recent nest-survey datasets with agencies, including SFC, the Public Works Department, and local authorities.
“So that they can make informed and sound decisions when proposing development projects for the people,” she said.
Officials note that the orangutan’s umbrella-species role makes smart siting a broader win, protecting forest services that many communities depend on.
