The Past, Present and Future of Elephant Landscapes in Asia

Abstract Habitat loss is a leading cause of species declines worldwide (1, 2). Using the Land Use Harmonization dataset (3) as the basis for ecological niche modelling, we quantify modelled changes in global suitable habitat over the past three centuries for Asian elephants, a megaherbivore representing diverse biomes. Between 1700-2015 over 60% of habitat suitable for elephants was lost, while average patch size declined 84-86%, and the largest patch decreased from 45% to 5%. Over half of the currently inhabited range is considered unsuitable for elephants, whereas suitable habitat is predicted to decline further from 2015-2099 across all six scenarios representing a range of emissions pathways and socioeconomic narratives. However, results vary by region and scenario in a non-linear manner, indicating that socioeconomic outcomes are as important as emissions pathways for the future of these habitats. Lao PDR, Thailand and Myanmar currently have lower elephant populations relative to the amount of available habitat. On the other hand, continued losses in densely settled areas such as India and Sri Lanka are expected to exacerbate human-elephant conflict. Only a few regions, notably peninsular Malaysia, Borneo, and Yunnan province, China, are predicted to have potential for habitat recovery. The most catastrophic losses across all range states occurred under a scenario of mid-range emissions but high regional inequities, leading to overexploitation of critical habitats. We conclude that steps to mitigate climate change must be taken alongside measures to ensure inter-regional social equity in order to safeguard these landscapes for elephants, humans and other species. SignificanceHuman land-use change is a leading driver of biodiversity loss, but effects are difficult to quantify over centennial timescales. Asian elephants occupy diverse biomes that have long been impacted by human activities and are thus indicative of the fates of numerous co-existing species. Over 60% of suitable elephant habitat has been lost since the 1700s and over half of the currently inhabited range may be considered unsuitable. Declines are predicted to continue to 2099 under six scenarios of global change across the majority of elephant range states, with the worst losses corresponding to a scenario representing mid-range emissions but high global inequity. Thus climate change mitigation strategies must include measures to facilitate equitable societies to safeguard and recover elephant landscapes, together with the unique biodiversity they represent.