title: Anticipated climate and land-cover changes reveal refuge areas for Borneo's orang-utans.
abstract: Habitat loss and climate change pose a double jeopardy for many threatened taxa, making the identification of optimal habitat for the future a conservation priority. Using a case study of the endangered Bornean orang-utan, we identify environmental refuges by integrating bioclimatic models with projected deforestation and oil-palm agriculture suitability from the 1950s to 2080s. We coupled a maximum entropy algorithm with information on habitat needs to predict suitable habitat for the present day and 1950s. We then projected to the 2020s, 2050s and 2080s in models incorporating only land-cover change, climate change or both processes combined. For future climate, we incorporated projections from four model and emission scenario combinations. For future land cover, we developed spatial deforestation predictions from 10 years of satellite data. Refuges were delineated as suitable forested habitats identified by all models that were also unsuitable for oil palm - a major threat to tropical biodiversity. Our analyses indicate that in 2010 up to 260,000 km(2) of Borneo was suitable habitat within the core orang-utan range; an 18-24% reduction since the 1950s. Land-cover models predicted further decline of 15-30% by the 2080s. Although habitat extent under future climate conditions varied among projections, there was majority consensus, particularly in north-eastern and western regions. Across projections habitat loss due to climate change alone averaged 63% by 2080, but 74% when also considering land-cover change. Refuge areas amounted to 2000-42,000 km(2) depending on thresholds used, with 900-17,000 km(2) outside the current species range. We demonstrate that efforts to halt deforestation could mediate some orang-utan habitat loss, but further decline of the most suitable areas is to be expected given projected changes to climate. Protected refuge areas could therefore become increasingly important for ongoing translocation efforts. We present an approach to help identify such areas for highly threatened species given environmental changes expected this century.
authors.affiliation: Durrell Institute of Conservation and Ecology (DICE), School of Anthropology and Conservation, University of Kent, Canterbury, CT2 7NR, UK.
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Struebig
authors.affiliation: Leibniz Institute for Zoo and Wildlife Research (IZW), Alfred-Kowalke-Straße 17, 10315, Berlin, Germany.|Department of Forestry and Ecosystem Science, University of Melbourne, Creswick, Vic., 3366, Australia.
authors.forename: Manuela
authors.initials: M
authors.lastname: Fischer
authors.affiliation: Center for International Forestry Research (CIFOR), P.O. Box 0113 BOCBD, Bogor, 16000, Indonesia.
authors.forename: David L A
authors.initials: DL
authors.lastname: Gaveau
authors.affiliation: Center for International Forestry Research (CIFOR), P.O. Box 0113 BOCBD, Bogor, 16000, Indonesia.|Borneo Futures, People and Nature Consulting International, Jakarta, Indonesia.|Australian Research Council Centre of Excellence for Environmental Decisions, School of Biological Sciences, The University of Queensland, Brisbane, Qld, Australia.
authors.forename: Erik
authors.initials: E
authors.lastname: Meijaard
authors.affiliation: Research Centre in Evolutionary Anthropology and Palaeoecology, School of Natural Sciences and Psychology, Liverpool John Moores University, Liverpool, UK.|Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, the Netherlands.
authors.forename: Serge A
authors.initials: SA
authors.lastname: Wich
authors.affiliation: Durrell Institute of Conservation and Ecology (DICE), School of Anthropology and Conservation, University of Kent, Canterbury, CT2 7NR, UK.
authors.forename: Catherine
authors.initials: C
authors.lastname: Gonner
authors.affiliation: Durrell Institute of Conservation and Ecology (DICE), School of Anthropology and Conservation, University of Kent, Canterbury, CT2 7NR, UK.
authors.forename: Rachel
authors.initials: R
authors.lastname: Sykes
authors.affiliation: Leibniz Institute for Zoo and Wildlife Research (IZW), Alfred-Kowalke-Straße 17, 10315, Berlin, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Wilting
authors.affiliation: Leibniz Institute for Zoo and Wildlife Research (IZW), Alfred-Kowalke-Straße 17, 10315, Berlin, Germany.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Kramer-Schadt
mesh_terms: D000818:Animals; D001893:Borneo; D057231:Climate Change; D017753:Ecosystem; D008962:Models, Theoretical; D057079:Pongo; D000068236:Refugium
keywords: South-East Asia; assisted colonization; biodiversity; deforestation; habitat suitability; orangutan; species distribution modelling; translocation