A startling impact: Heart of Borneo helps predict the future of Borneo’s mammals
Heart of Borneo has been involved in critical research to predict the future of Borneo’s mammals from the effects of deforestation and climate change. The results are startling as our very own Tim van Berkel, co-author of the paper, explains.
Deforestation rates in Borneo are amongst the highest in the world and we know that the amount of remaining forest is only half that of its original extent, and that continued land cover and climate change, amongst other human impacts such as hunting and habitat fragmentation, are negatively impacting Bornean mammals. What we don’t know however, is how future changes in land cover and climate will impact the distribution of mammals on Borneo.
A group of scientists, led by Matt Struebig and Andreas Wilting, turned their attention to this problem and more importantly, identified areas that need to be prioritised to ensure adequate conservation of the Bornean mammals.
The study, to which the Heart of Borneo Project contributed through camera trap records, used 6921 occurrence records. The records comprised 81 mammal species; 13 primates, 23 carnivores, and 45 bats which were used to assess current distributions and predict future ranges under influence of land cover and climate change.
One of the problems the researchers faced however was that most of these records were located in Sabah and very few originated from the forests of Kalimantan, thereby potentially introducing bias in distribution models. This made our contributed carnivore records from remote and understudied Central Kalimantan, which included the endangered and rare otter-civet, all the more valuable.
The Effect of Climate Change
The authors first examined the effect of just climate change on mammal species, and their findings are frightening. They predicted that under this scenario up to 36% of the Bornean mammals are set to lose 30% or more of their habitat by the year 2080, with the lowland forests being hit hardest. But, when the effects of future deforestation were added the impacts were even more severe, increasing the proportion of species to lose comparable habitat to 30-49%.
These findings raise an important conservation question; if so many habitats will be lost, where should we focus our efforts in order to most effectively, efficiently and comprehensively conserve these species?
Fortunately the authors did some forward planning and also addressed this issue, and this is where we can find some positive news. Most large, protected areas are located at mid to high elevation.
Climate change is expected to shift species ranges upward, so if species are able to colonise these areas, less additional protected land is needed than if land cover change were to happen without the influence of climate change. The authors estimate this to be only around 28,000km2 or 4% of the island – an ironically positive side effect of climate change. Unfortunately, the land that is currently set aside for conservation purposes is not enough to accommodate some of the wide-ranging species, and additional land is required to effectively conserve most mammals.
It seems unlikely that enough conservation area will be granted in the future. Any land that is not designated as conservation area is allocated either for conversion into agriculture, or marked as production forest. The land that is needed for conservation would therefore be made available in collaboration with timber concession owners in Kalimantan, and plantation holders in Malaysia and Brunei. The authors stress that partnerships with these stakeholders will be of critical importance to ensuring conservation outside protected areas. This should include a great reduction in hunting, which occurs mostly in logged forest, and logging roads should be closed as they provide easy access to hunters and illegal loggers.
The authors provided a spatial plan to safeguard Borneo’s diversity (see the figure below). If we can ensure that these areas are adequately protected, then there might be a future for Bornean mammals.
What does the future hold?
But what would happen after 2080? Will the climate temperature have surpassed the critical warming threshold of 2°C above pre-industrial levels? Will deforestation increase to such an extent that even the protected areas will not provide adequate protection to maintain forest cover? We certainly hope not, and believe that a different future awaits. If it is up to us, and if major oil palm and timber extraction companies stand by their non-deforestation commitments, we predict a brighter future, even before 2080. A future where deforestation is in the past, and reforestation is the norm, and where the mammals of Borneo can roam far and wide again.
Citation: Struebig et al., Targeted Conservation to Safeguard a Biodiversity Hotspot from Climate and Land-Cover Change, Current Biology (2015), http://dx.doi.org/10.1016/j.cub.2014.11.067
The full article can be accessed through http://www.cell.com/current-biology/abstract/S0960-9822%2814%2901565-6
Tim van Berkel is co-Founder and Scientific Director of the Heart of Borneo Project. If you have any questions about this research, or any other research related matters, please use the contact form on this site.