In 2011, the German conservationist Robert Risch was hiking along the banks of a river at the northern limits of Tabin wildlife reserve, home to pygmy elephants, orangutans and the Bornean banteng, an endangered species of wild cattle. Risch was expecting to see long stretches of wilderness but instead saw a swathe of palm oil plantations and electric fences.
“I found elephant tracks coming from Tabin following the river to the north until they reached the electric fence. Then the tracks turned around back to Tabin,” says Risch. “No choice.”
Located in the Malaysian state of Sabah on the island of Borneo, this plot of land lies between the Tabin and Kulamba wildlife reserves. But what should have been a clear path between the reserves was blocked to wildlife.
Risch founded the Rhino and Forest Fund (RFF) in 2009 with the aim of reconnecting Tabin with Kulamba and creating a 200,000-hectare (775 sq mile) wilderness. Kulamba already abutted the Lower Kinabatangan-Segama wetlands, a Ramsar site of international importance.
In 2019, the RFF bought 65 hectares (160 acres) of land and gave it to the Sabah forestry department for conservation. Although RFF’s purchase was small, it represented the first dryland connection between the two parks in decades, providing wildlife with an 800-metre-wide corridor, large enough for elephants.
As soon as they took the fences down, elephants began moving through the area again and previously disconnected populations were reunited. The region is home to several hundred Bornean pygmy elephants, which have been isolated from mainland elephants for 300,000 years and represent a distinct evolutionary population.
RFF also began restoring the land by planting native trees and grasses, clearing invasive species and creating a small lake.
“[In 2022], after working in the area for a full decade, we saw for the first time orangutan, proboscis monkey, red leaf monkey and Storm’s stork [considered to be the rarest of all storks, with probably fewer than 500 left worldwide] in our restoration site,” Risch says.
Benoît Goossens, director of the Danau Girang field centre, a research facility managed by the Sabah wildlife department and Cardiff University, says restoring “connectivity” is one of the state’s key aims for many of its charismatic species. For example, there are about 1,700 critically endangered Bornean orangutans across the territory, but many are cut off from each other.
“The major threat for these species in this landscape is not deforestation or poaching, but fragmentation,” says Marc Ancrenaz, head of the local community-based conservation organisation Hutan, and an expert on orangutans.
“[Our] work in Kinabatangan and other areas shows that creating forest corridors between isolated patches of forest occupied by orangutans contributes to sustaining viable orangutan meta-populations [separated groups of one species] over large landscapes,” he says.
The next step in RFF’s plan is to acquire additional plantation land to widen the corridor. It is raising funds to buy another 540 hectares for about $5m (£4m).
Land here is far more expensive than in many wilderness areas, since any buyer could easily use it as a plantation for the highly lucrative palm oil industry – the dominant crop in the region. “The special thing with oil palm is it’s highly productive,” says Risch. “So buying oil palm land for conservation is not a low hanging fruit to pick.”
The palm oil industry has boomed in Malaysia and Indonesia over the last few decades, leading to vast deforestation, loss of wildlife and human-wildlife conflict. In Sabah, about 1.5m hectares are planted with oil palm. At the same time, the state has committed to protecting 30% of its undeveloped land area by 2025.
Ancrenaz believes it is important to work with the palm oil industry to set aside more areas for conservation, especially along riverbanks. Promoting projects such as agroforestry, which benefit both biodiversity and people, are also important, he says.
“Although creating protected areas must remain the cornerstone for conservation, this approach alone is not enough for those wide-ranging species,” says Ancrenaz.
“We also need to manage better the non-protected landscapes occupied and used by people and where the animals are found.”
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