Conservation news

The Pan Borneo Highway could divide threatened wildlife populations

  • Crews are set to begin construction on a stretch of Malaysia’s Pan Borneo Highway in eastern Sabah state, involving the widening of the road from two lanes to four.
  • The new divided highway will cross the Kinabatangan River and pass through a critical wildlife sanctuary that’s home to orangutans, elephants and proboscis monkeys, along with other wildlife species already hemmed in by the region’s oil palm plantations.
  • Planners and politicians hope the road will stimulate local economies and bring in more tourists.
  • Conservationists and scientists, however, are concerned that the highway could further section off animal populations and damage the current tourism infrastructure, unless certain mitigation measures are introduced.

This is the fourth article in our six-part series “Traveling the Pan Borneo Highway.” Read Part One, Part Two and Part Three.

BATU PUTEH, Malaysia — They call it the “corridor of life.” Amid a sea of oil palm plantations, narrow strips of forests that fringe the Kinabatangan River in Malaysia teem with iconic wildlife.

Established as a wildlife reserve in the 1990s, the Lower Kinabatangan Wildlife Sanctuary has become one of the biggest tourist draws in the state of Sabah, in part because there are few places where it’s easier to see some of Southeast Asia’s best-known wild animals. Pot-bellied proboscis monkeys and eight species of hornbills are so easy to spot that tour boats from the outfitters based around the towns of Sukau and Batu Puteh sometimes won’t even slow down for them. And chance encounters with orangutans, crocodiles (observed safely from longboats) and even Borneo’s diminutive variant of the Asian elephant certainly aren’t rare.

A map of the Lower Kinabatangan Wildlife Sanctuary at the entrance to the town of Batu Puteh in Sabah, where the local tourism cooperative KOPEL is located. Image by John C. Cannon/Mongabay.

Still, state and local leaders see the area’s potential for tourism as largely unrealized. Like politicians in other parts of Sabah, they aim to bring in more visitors, and provide locals with better access to services and markets, by improving connections to other parts of Sabah — specifically with the Pan Borneo Highway project. It calls for crews to widen the two-lane road that crosses the Kinabatangan River on its way from Lahad Datu to Sandakan into a four-lane, divided highway. The project plans also include a four-lane bridge over the Kinabatangan River where it crosses at the town of Batu Puteh. Currently, a two-lane, steel trestle bridge spans the river, clanking and shuddering under the weight of passing traffic, especially the ubiquitous palm oil-toting tankers.

Scientists and conservation groups, however, have raised concerns about expanding the existing road, which they say could further carve up already fragmented wildlife populations. Even at two lanes, the road has proven an insurmountable impediment to elephants crossing back and forth. All of the tracking data from teams at WWF-Malaysia and the Danau Girang Field Centre just downriver show that elephants remain on one side of the road and that they won’t cross.

Tourists frequently spot Bornean orangutans (Pongo pygmaeus) on the Kinabatangan River. Image by John C. Cannon/Mongabay.

There’s even some evidence that the noise from the road — or perhaps, more accurately, the vibration of the bridge — keeps crocodiles from swimming underneath it, so its construction in the late 1990s likely split the river’s crocodile population in two.

Experts fear that a wider, divided road would further hinder the passage of wildlife, hemming them into even smaller patches of habitat. It also increases the chances that frustrated animals will come into contact with local residents and oil palm plantation workers. They caution that the frequency of roadkill could spike, with disastrous consequences for both animals and people. One video shows a panicked and confused baby elephant bumping into cars in other parts of Sabah. In Thailand, passers-by recorded a devastating nighttime crash involving a bus and an elephant — a scene that those concerned about the arrival of the Pan Borneo Highway believe could happen in Sabah.

Under the existing bridge on the north bank of the river in Batu Puteh sits the headquarters of KOPEL, an internationally recognized tourism cooperative. Households throughout the community participate, hosting travelers in homestays and benefiting financially, while the tourists have easy access to the river’s wildlife delights. KOPEL also runs an “Eco Camp” downriver for more adventurous visitors, anchored by a steady stream of school groups, looking to spend their nights in the forest. There, they also have the chance to participate in the restoration of forest throughout the wildlife sanctuary. The organization’s leaders are concerned, however, that any realignment of the existing bridge could force KOPEL to make a costly move.

Expansion and realignment of the Batu Puteh bridge for the Pan Borneo Highway could force KOPEL, a local tourism cooperative, to move its headquarters. Image by John C. Cannon/Mongabay.

Downriver, plans for a bridge linking the town of Sukau with more remote communities east of the river have been revived, even though the previous state government abandoned a similar project in 2017. The Sukau bridge project isn’t part of the Pan Borneo Highway, though longtime proponents echo similar claims that it would bring development, tourism and better access to health care for local residents. Curiously, though, the environmental impact assessment for the project only includes plans for road construction, not a bridge, according to several sources, even though the word “bridge” remains in the title.

WWF-Malaysia has also had a chance to review the assessment. The group cautions that, “A road built in this area will cause further fragmentation and open up access to illegal wildlife hunting.” As a result, WWF-Malaysia has called for the assessment to include a study on how road construction in this area will affect wildlife.

Minister of Works Baru Bian said that his office backs the construction of wildlife crossings, pointing to their inclusion in parts of Peninsular Malaysia’s Central Spine Road. Baru said that eco-viaducts there allow large animals to pass underneath the roads without posing a danger to them or to motorists.

Young trees grow at a forest restoration site, providing a buffer between the oil palm plantation behind and the Kinabatangan River. Image by John C. Cannon/Mongabay.

But research in Peninsular Malaysia has shown that these pinch points serve as ideal spots for natural predators as well as poachers to hang out in search of their prey. To deal with that threat, more wildlife rangers will be needed to keep poachers at bay, Sheelasheena Damian, a policy analyst at WWF-Malaysia, told Mongabay.

“The development of roads in Kinabatangan can have detrimental effects to wildlife as it creates access for poachers to enter forest reserves,” Damian said. “The government must take this into consideration when planning development in biodiversity hotspots such as Kinabatangan.”

Just recently, the tusks of five Bornean elephants, almost certainly victims of poaching in Sabah, turned up across the border in the Indonesian province of North Kalimantan.

The proboscis monkey (Nasalis larvatus) is one of several threatened species protected by the wildlife sanctuary. Image by John C. Cannon/Mongabay.

Biologist Benoît Goossens, who directs the Danau Girang Field Centre, agrees that wildlife viaducts aren’t a panacea.

He and his colleagues have been using drones to map potential sites for the pathways once the road is in place. Imperative, he says, is that they link sections of good forest on both sides of the road, as prior research has shown. He also posits that ecobridges made to be as natural as possible might be more successful than underpasses, which are typically just dirt pathways without vegetation running under the road.

Any connectivity in wildlife populations rests on the contingency that animals actually use such corridors, which is by no means guaranteed.

Long-tailed macaques (Macaca fascicularis) feeding along the Kinabatangan River. Image by John C. Cannon/Mongabay.

Still, at this point, with construction set to move forward, Goossens acknowledged that including some sort of wildlife crossing is the best they can hope for in terms of minimizing the impacts of the highway.

“It’s that or nothing,” he said. The alternative — a four-lane, divided highway that cuts through this critical slice of habitat in Sabah without any concessions for the region’s animals — is stark.

“You can say goodbye to the ‘corridor of life’ in the Kinabatangan,” Goossens said.

Continue to Part Five.

Banner image of a saltwater crocodile (Crocodylus porosus) in the Kinabatangan River by John C. Cannon/Mongabay.

John Cannon is a staff writer at Mongabay. Find him on Twitter: @johnccannon

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