Long-Term Field Data and Climate-Habitat Models Show That Orangutan Persistence Depends on Effective

Background: Southeast Asian deforestation rates are among the world’s highest and threaten to drive many forestdependent species to extinction. Climate change is expected to interact with deforestation to amplify this risk. Here we examine whether regional incentives for sustainable forest management will be effective in improving threatened mammal conservation, in isolation and when combined with global climate change mitigation. Methodology/Principal Findings: Using a long time-series of orangutan nest counts for Sabah (2000–10), Malaysian Borneo, we evaluated the effect of sustainable forest management and climate change scenarios, and their interaction, on orangutan spatial abundance patterns. By linking dynamic land-cover and downscaled global climate model projections, we determine the relative influence of these factors on orangutan spatial abundance and use the resulting statistical models to identify habitat crucial for their long-term conservation. We show that land-cover change the degradation of primary forest had the greatest influence on orangutan population size. Anticipated climate change was predicted to cause reductions in abundance in currently occupied populations due to decreased habitat suitability, but also to promote population growth in western Sabah by increasing the suitability of presently unoccupied regions. Conclusions/Significance: We find strong quantitative support for the Sabah government’s proposal to implement sustainable forest management in all its forest reserves during the current decade; failure to do so could result in a 40 to 80 per cent regional decline in orangutan abundance by 2100. The Sabah orangutan is just one (albeit iconic) example of a forest-dependent species that stands to benefit from sustainable forest management, which promotes conservation of existing forests. Citation: Gregory SD, Brook BW, Goossens B, Ancrenaz M, Alfred R, et al. (2012) Long-Term Field Data and Climate-Habitat Models Show That Orangutan Persistence Depends on Effective Forest Management and Greenhouse Gas Mitigation. PLoS ONE 7(9): e43846. doi:10.1371/journal.pone. 0043846 Editor: Brian Gratwicke, Smithsonian’s National Zoological Park, United States of America Received May 3, 2012; Accepted July 24, 2012; Published September 7, 2012 Copyright: 2012 Gregory et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: This research was funded by an ARC Discovery Grant awarded to DAF and BWB (DP1096427). BG was supported by a Darwin Initiative for the Survival of Species (Grant no. 09-016, DEFRA, UK) and Cardiff University. KOCP is supported by Apenheul Primate Park, ZooParc de Beauval, Cleveland Metroparks Zoo, Chester Zoo, Columbus Zoo, Houston Zoo, Zoo de La Palmyre, Oregon Zoo, Philadelphia Zoo, Phoenix Zoo, Saint Louis Zoo, Utah’s Hogle Zoo, Woodland Park Zoo, Abraham Foundation, Arcus Foundation, Balikpapan Orangutan Survival Foundation (NL), Shared Earth Foundation, Elephant Family Foundation, Ensemble Foundation, Mohamed bin Zayed Foundation, Shining Hope Foundation, World Women Work Foundation, the WoodTiger Fund, Wildlife Conservation Network, US Fish and Wildlife Services Great Ape Conservation Fund, North England Zoological Society and the Orangutan Project. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared that no competing interests exist. * E-mail: stephendavidgregory@gmail.com