Road and rail projects throughout Indonesian Borneo threaten to fragment a third of the forest habitat currently accessible to the island’s wildlife, according to a new study.

Completion of ongoing and planned road construction poses an “imminent threat” to forests in Kalimantan, as the Indonesian portion of the island of Borneo is known, according to a team of researchers from Indonesia and Australia. Their findings were published on January 15 in the journal Scientific Reports.

Landscape connectivity will decline from 89% to 55%, according to the study. “That’s an alarming figure,” said lead author Mohammed Alamgir, an environmental scientist at James Cook University in northern Queensland. “And it’s just the tip of the iceberg, because the new roads and rail projects will open up the forest like a flayed fish, allowing illegal colonists, poachers and miners to invade the forest and cause even more forest disruption.”

Using spatial analysis and satellite monitoring, the researchers evaluated large-scale road-building projects in Kalimantan under the Indonesian government’s 2011-2025 development master plan. These include an upgrade of 3,316 kilometers of the Trans-Kalimantan Highway in southern Kalimantan; 1,920km of new roads in northern Kalimantan, skirting the border with Malaysian Borneo; and additional highways and expressways throughout Central, South, East and North Kalimantan.

The report noted that the primary goal of this new infrastructure was to increase commercial connectivity and primary industries, particularly coal mining, palm oil production, and industrial logging.

“However, little is known of the potential impacts of this new infrastructure on Bornean forests or biodiversity,” Alamgir said.

The study shows that ongoing and planned road building would alter the spatial pattern of forests in Kalimantan, creating more fragmented patches of forest and a greater span of forest habitat edged by roads, threatening forest corridors used by wildlife. Such a transformation, the authors say, is “worrisome” because the region hosts one of the world’s largest tracts of native tropical forest, spanning 370,000 square kilometers – an area a quarter the size of Alaska.

The roads, the study says, would cut through 25 protected areas that are currently free of any roads, including Kayan Mentarang National Park, one of the largest remaining protected areas in Kalimantan. Some 17 other protected areas, mostly in southern Borneo, will be impacted by the planned upgrades of existing roads, the study says.

Most of the road projects, planned and underway, fall inside or along the borders of primary or selectively logged forests, suggesting that “much road expansion will be at the expense of native forest.”

‘Very high impact’ roads

The researchers classified 634 kilometers of this infrastructure as “very high impact,” as it will cut through protected areas; 1,472km as “high impact” for going through primary or peat forest; and 1,242km as “moderate impact” for going through selectively logged or regrowth forests.

“The currently planned and ongoing expansion of roads and rail lines in Indonesian Borneo will have severe deleterious impacts on native forests in the region,” Alamgir said.

“These projects will promote and shape future investments, particularly for logging, mining, and oil palm developments, but will have major impacts on existing forests and wildlife, and will carry serious and poorly recognized economic, financial, social, and political risks,” he said.

The researchers have called on the Indonesian government to halt the projects deemed “very high impact,” and to impose stringent environmental mitigation efforts and law enforcement on those classified as “high impact” and “moderate impact,” should they proceed.

“Borneo’s forests and rare wildlife have already been hit hard, but planned roads and railways will shred much of what remains, slicing across the largest remaining forest blocks,” said co-author Jatna Supriatna, a conservation biologist at the University of Indonesia.

‘Daggers to the heart’

“These projects will be like daggers in the heart of the Borneo rainforest,” Alamgir said. “We implore the Indonesian government to reconsider them, because they’ll open a Pandora’s box of crises for the world’s biologically richest forests.”

Kalimantan is the third most populated region in Indonesia, after the islands of Java and Sumatra, both of which are notably smaller in size, and the government estimates the population of about 16 million will increase by nearly a third to more than 20 million by 2035. The region is home to indigenous communities whose lives revolve around intact forests, as well as to critically endangered species such as Bornean orangutans.

But industrial-scale forest clearing in recent decades – for mining, logging, and palm oil cultivation – has threatened the well-being and lives of both human and animal inhabitants of Kalimantan. The extensive draining of the island’s peat forests to make way for agriculture has also rendered the organic-rich soil highly susceptible to fires. In 2015 alone, nearly half of the deforestation recorded in Indonesia, nearly 8,000 square kilometers of forest loss, occurred here.

Yet there persists a legitimate need for roads and railways that would serve as an economic catalyst for the region, even as they carve up the shrinking forests, said Kiki Utomo, an environmental engineering lecturer at Tanjungpura University in West Kalimantan, who was not involved in Alamgir’s research. The state of the island’s infrastructure is dire, he said, lagging even less-developed provinces in Indonesia’s east.

‘Dire’ need for infrastructure

“If there’s a small pothole in a road in Java, people will make a big deal out of it. But in Kalimantan, the road itself could be in a hole and people will just accept it as is,” Kiki told Mongabay by phone.

He said the island’s low population density meant there was historically little incentive for the government to build an extensive road network. “If there’s any infrastructure development, it’s usually in [more populated] coastal areas like in the southeast or south of Kalimantan, or in East Kalimantan province, where there are oil reserves,” he said. “But the rest of Kalimantan has been underdeveloped for years. What we have now isn’t interconnected, and its condition isn’t the best.

“We’re in dire need of infrastructure development, especially roads,” Kiki added.

He said the concerns raised by the new study were fair and reflected the views of many conservationists across Kalimantan. He agreed that the impacts of state-backed road-building projects on forests and biodiversity needed to be considered in the environmental impact assessments carried out by the government.

But Kiki said shutting down any of the projects would be unwise, given the inadequacy of alternative transport options, as carrying freight by river is impossible during the dry season, and building new airports would require the government to subsidize ticket prices due to the projected low demand.

“It’s impossible to not build [road] infrastructure as this is something that the people here have wanted for so long,” Kiki said.

With legislative and presidential elections slated for April this year, voters in Kalimantan will go for candidates who support road projects in their respective constituencies, Kiki said. But voters are also sensitive to the negative impacts of road development, such as forest encroachment, illegal logging and wildlife poaching, Kiki said.

‘Revise roads, protect forests’

He said the government should revise the planning of road projects that cut through conservation areas, such as national parks and nature reserves, as these zones are supposed to be protected by law. He also called on the government to beef up law enforcement against illegal activities inside forests.

The government appears to have adopted mitigation efforts in planning the road works in Kalimantan, said Irwan Gunawan, director of the Kalimantan program at WWF-Indonesia, who was not involved in the recent study. He said the government had involved civil society groups to draw up guidelines for sustainable and environmentally friendly road construction.

These technical guidelines include exempting core zones of protected areas from any development; requiring developers to put grassroots conservation strategies into place; limiting the gap between a road and the edge of the adjacent forest to 25 meters to minimize tree clearing; and banning any type of exploitation (logging, poaching) along the roads. The developers are also required to remove any construction waste from forests and dispose of it properly, as well as involve residents in monitoring the work.

Irwan said some of the newly built roads were already benefiting local communities, cutting the cost of transporting their produce from farms to towns and cities.

“We appreciate the fact that the government is trying to adopt sustainable infrastructure concepts, albeit in a basic way,” he said. “However, we haven’t received any feedback on whether all of this has been completely adopted in the implementation.”

Irwan called for greater transparency from the government to ensure that both development plans and conservation efforts continued to be aligned. “The call from conservationists is very simple: nobody is against development, but it mustn’t compromise the biodiversity value,” he said.

– This story first appeared on Mongabay. An original version can be accessed here