Journalism and science work together to expand the known range of a rare great ape

21 Apr 2026

In October 2025, Mongabay published a story (first first published by Mongabay Indonesia here and here) that explained how researchers had confirmed that the critically endangered Tapanuli orangutan, previously thought to live only in Sumatra’s Batang Toru forest, also inhabited a peat swamp forest 32 kilometers (20 miles) away in the Lumut Maju village forest.

The finding was made public in Mongabay’s report after Mongabay Indonesia journalist, Junaidi Hanafiah, accompanied a field team from the Sumatran Orangutan Conservation Foundation-Orangutan Information Centre (YOSL-OIC) on a survey of Lumut Maju. On Sept. 26, 2025, Hanafiah successfully photographed a mother and infant orangutan in the forest. This was the first confirmed visual record of Tapanuli orangutans outside Batang Toru.

Hanafiah’s photographs and field documentation, alongside prior reports of nests and sightings, laid the groundwork for a scientific investigation. DNA analysis of fecal samples verified the Lumut Maju apes as Tapanuli orangutans, marking the first confirmed record of the species outside Batang Toru.

Impact

The finding highlighted the conservation value of nonprotected peat swamps, which are rapidly being cleared for oil palm plantations, threatening the orangutans’ survival. “In 2025 alone, there’s been exceptional land clearing of forests, and now the remaining forest is less than 1,000 hectares [2,500 acres],” said Rio Ardi, research manager at YOSL-OIC.

This finding possibly extends the known range of the species, previously thought to be limited to the Batang Toru landscape. According to YOSL-OIC, the discovery provides critical information for conservation strategies, highlighting the importance of overlooked peat swamp forests as potential habitats for the critically endangered Tapanuli orangutan.

Mongabay Indonesia journalist Junaidi Hanafiah documented the Tapanuli orangutan in its newly identified peat swamp habitat in North Sumatra. Image by Mongabay Indonesia.
Mongabay Indonesia journalist Junaidi Hanafiah documented the Tapanuli orangutan in its newly identified peat swamp habitat in North Sumatra. Image by Mongabay Indonesia.

The isolated orangutan group is believed to number fewer than 100 individuals, far below the 250 individual threshold for a sustainable population. Reestablishing a forest corridor between Lumut Maju and Batang Toru is considered impractical, as the landscape is heavily fragmented by plantations and infrastructure. Conservation experts say this makes relocation the most realistic long-term strategy. Moving these orangutans to the larger, protected forest block of Batang Toru could help increase genetic diversity within the species and secure their future, they say.

In the months following publication, the reporting also resulted in early engagement from the Central Tapanuli local government. According to local authorities, officials in Lumut Sub-district subsequently sought consultation with the YOSL-OIC to discuss appropriate next steps regarding the presence of orangutans in the area. The discussions focused on whether the habitat should be maintained to support long-term coexistence between humans and orangutans or whether relocation would be necessary based on scientific assessments. This response indicates that the reporting helped trigger coordination between local government and conservation organizations and supported evidence-based decision-making on species protection and landscape management.

This newly confirmed cluster in Lumut Maju, seen first through a journalist’s lens, underscores the power of field-based environmental journalism to generate actionable conservation knowledge, especially in fast-changing ecosystems like Sumatra’s peatlands. As efforts continue to protect the forest, Mongabay’s reporting helped shift awareness and priorities in the race to save this critically endangered species.

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Banner image: A mother and infant Tapanuli orangutan were directly sighted in the Lumut Maju peat swamp forest in North Sumatra. Image by Junaidi Hanafiah/Mongabay Indonesia.