Anticipated climate and land-cover changes reveal refuge areas for Borneo's orang-utans

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 km2 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 northeastern 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 km2 depending on thresholds used, with 900–17 000 km2 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

Hybrid apes in the Anthropocene: burden or asset for conservation?

1. Conservationists often view hybrid animals as problematic, at least if anthropogenic influence caused the intermixing to occur. However, critics propose that humans should respect nonhuman autonomy, reject essentialism, and accept the creatures they have helped create. 2. Based on two case studies of our own ethological, genetic, and ethnographic research about chimpanzee and orangutan subspecies hybrids, we assess what, if anything, should be done about such animals. We consider problems posed by cross-bred apes relating to: 1) Breeding—Do hybrids really experience reduced reproductive success? How are population-level concerns and welfare of individual animals balanced in conservation breeding? 2) Essentialism—Are anti-hybrid arguments based on essentialist or purist thinking? Does essentialism vary by conservation context? 3) Pragmatism—How do socio-economic circumstances influence whether hybrids are embraced or ignored? Does the erosion of ‘untouched nature’ render hybrids more important? 3. We show that answers to these questions are complex and context-specific, and that therefore decisions should be made on a case-by-case basis. For example, we find that anti-hybrid arguments are essentialist in some cases (e.g. ape management in zoos) but not in others (e.g. ape reintroduction). Thus, rather than present recommendations, we conclude by posing nine questions that conservationists should ask themselves when making decisions about taxonomic hybrids