Future hanging in balance? Borneo orang-utan. Photo by Rhett Butler.
The study, published in the journal PLoS ONE, overlays orangutan distribution with land use regulations in Malaysian and Indonesian Borneo. Borneo has suffered high rates of deforestation, logging, and forest conversion for industrial plantations in recent decades, endangering the world’s largest surviving populations of orangutans.
The authors, led by orangutan specialist Sege Wich of Liverpool John Moores University, found that 78 percent of forest currently inhabited by orangutans in Borneo is unprotected. Of that 29 percent is under logging concessions, 25 percent is licensed for conversion to industrial oil palm and timber plantations, and 24 percent lies outside protected areas or concessions.
The researchers then modeled the impact of future land use on the distribution of orangutans. They estimate that under a business-as-usual scenario “at best only 51% of the current orang-utan distribution (in protected areas and logging concessions) would remain”. They warn that the reality however could be far worse due to hunting, which is a substantial cause of orangutan mortality in Indonesian Borneo but isn’t factored into the model. They also note further threats from industrial mining operations, which in Indonesia can be granted in nominally protected areas, and illegal encroachment into officially protected areas.
Conversion of logged forest to an oil palm plantation in Borneo. Photo by Rhett Butler.
But the researchers also ran a more optimistic scenario under which the Malaysian and Indonesian governments zone forests outside protected areas and current concessions for selective logging, which research suggests can maintain orangutan populations when done properly, rather than oil palm and timber plantations.
“There is now a large quantity of evidence indicating that selectively logged natural forests can play an important role in the conservation of orang-utan populations,” they write. “However, it is important to recognize that good management is crucial to the effectiveness of these concessions for orang-utan conservation. Concessions where timber is harvested at unsustainable rates tend to have far lower orang-utan densities, and other factors such as damage to residual stands and hunting control are also very important. Certification, for example through the principles and criteria of the Forest Stewardship Council (FSC), could guarantee such sustainable management.”
“Selectively logged natural forest constitutes the highest percentage of the orang-utan distribution of any land-use type. Thus, the future of the species largely depends on the strength of the commitments by governments and companies to reduce deforestation and forest degradation rates in logging concessions and to maintain these forests for sustainable timber harvest over the long-term.”
Under this second scenario, “approximately 64% of the current orang-utan distribution would remain if all such forests, protected areas and logging concessions maintain orang-utans.”
Deramakot Forest Reserve, a Dipterocarp forest managed as an FSC-certified concession in Sabah, Malaysia. Deramakot is considered the “gold standard” for tropical forest management. Photo by Rhett Butler.
To avoid the worst outcome for orangutans, the paper argues for spatial planning that incorporates the best science and accounts for the value of ecosystem services afforded by healthy forests.
“To ensure long-term survival of orang-utans, a masterplan at the landscape level is needed that will consider all remaining viable populations as well as all the different land uses that are active within the orang-utan’s range. Such a master plan should clarify which possible land uses and managements are allowed in the landscape and provide new standardized strategic conservation policies (e.g., a policy for logging concession management in orang-utan areas),” they write.
“Such a process should make much better use of values of ecosystem services of forests such as water provision, flood control, carbon sequestration, and sources of livelihood for rural communities. Presently land use planning is more driven by vested interests and direct and immediate economic gains, rather than by approaches that take into consideration social equity and environmental sustainability. Both the Malaysian and Indonesian governments have committed to the long-term maintenance of natural capital, but this requires the use of scenarios that integrate the need for both economic growth and environmental and social sustainability when making land use decisions.”
CITATION: S.A. Wich et al. (2012) Understanding the Impacts of Land-Use Policies on a Threatened Species: Is There a Future for the Bornean Orang-utan? PLoS ONE 7(11): e49142. doi:10.1371/journal.pone.0049142