Tigers on the Move: The Impact of Climate Change on Tiger Distribution in Nepal.

The Bengal tiger (Panthera tigris tigris), a flagship and umbrella species of the South Asian forest ecosystem, has declined dramatically in population and geographic distribution due to human-caused habitat fragmentation and poaching over the past century. Global tiger populations may persist in the next century only if the size and quality of the current habitat remain unchanged. Our first-of-its-kind study in Nepal assesses whether these habitat requirements are in place through an analysis of habitat suitability to predict the future habitat of tigers in varying climatic scenarios across the country. We collected tiger-presence location (GPS points) from tiger surveys conducted by the Department of National Parks and Wildlife Conservation, Nepal, in 2018 and 2022 across the country. We used MaxEnt software in varying Shared Socio-economic Pathways (SSP 245 and 585) employing eight bioclimatic and two topographic variables to predict the future habitats of the tiger in 2050, 2070, and 2090. In the SSP 245 scenario, tiger habitat could increase for all three time periods, but in the SSP 585 scenario, the habitat will increase only in 2050. Interestingly, in both scenarios, tiger habitat will increase by more than 80% in 2050. The expanded habitat in all scenarios is outside of protected areas and northeast of the current habitat. This indicates that extreme climate change scenarios with more industrialization, urbanization, and land use change have a greater impact on tiger habitat. Furthermore, tiger habitat qualitatively shifts from protected areas to outside protected areas in the human-dominated landscape. This creates more challenges for conservationists and managers as human-tiger interaction may surge. Proactive management solutions to protect Nepal's tigers for the next century could include expanding or establishing new protected areas, establishing connectivity and corridors between the tiger habitats, in addition to anticipatory efforts to address human-wildlife conflicts that will emerge in this changing landscape.