Abstract
Habitat loss drives species’ declines worldwide, but is seldom quantified over centennial timescales. We constructed ecological niche models for Asian elephants based on land-use change between 850-2015, and predictions under six different climate/socioeconomic scenarios from 2015-2099. We find that over 64% of suitable natural habitat across diverse ecosystems was lost over the past three centuries. Average patch size dropped 83% from approximately 99,000 km2 to 16,000 km2 and the area occupied by the largest patch decreased 83% from ~ 4 million km2 (45% of area) to 54,000 km2 (~7.5% of area). Over half of current elephant range appears unsuitable. Habitat availability is predicted to decline further this century across all scenarios. The most severe losses occur under RCP3.4-SSP4, representing mid-range emissions but high regional inequities. We conclude that climate change mitigation measures must include policies to ensure inter-regional socioeconomic equity to safeguard landscapes for elephants, humans, and other species.
Competing Interest Statement
The authors have declared no competing interest.
Footnotes
Introduction updated to clarify that original sampling locations represent suitable natural habitat that does not contain heavy anthropogenic activity; Figure 1 updated to extend analyses back to the year 850; Methods, results and supplementary text provides more detail on future scenarios; discussion addresses limitations with definition of natural habitats and modelling studies; new supplementary figure S3 shows suitable habitat in year 2015 scenarios in the extant range and buffer regions at 25-100km; new supplementary figure S6 shows suitable habitat in range+buffer by year 2099 under six scenarios; figure S7 shows fragmentation patterns in the future under a different binarization threshold value.
