Climate refugia of snow leopards in High Asia

Rapid warming in High Asia is threatening its unique ecosystem and endemic species, especially the endangered snow leopard (Panthera uncia). Snow leopards inhabit the alpine zone between snow line and tree line, which contracts and expands greatly during glacier-interglacial cycles. Here we assess impacts of climate change on global snow leopard habitat from the last glacial maximum (LGM; 21 kyr ago) to the late 21st century. Based on occurrence records of snow leopards collected across all snow leopard range countries from 1983 to 2015, we built a snow leopard habitat model using the maximum entropy algorithm (MaxEnt 3.3.3k). Then we projected this model into LGM, mid-Holocene and 2070. Analysis of snow leopard habitat map from LGM to 2070 indicates that three large patches of stable habitat have persisted from the LGM to present in the Altai, Qilian, and Tian Shan-Pamir-Hindu Kush-Karakoram mountain ranges, and are projected to persist through the late 21st century. These climatically suitable areas account for about 35% of the snow leopard's current extent, are large enough to support viable populations, and should function as refugia for snow leopards to survive through both cold and warm periods. Existence of these refugia is largely due to the unique mountain environment in High Asia, which maintains a relatively constant arid or semi-arid climate. However, habitat loss leading to fragmentation in the Himalaya and Hengduan Mountains, as well as increasing human activities, will present conservation challenges for snow leopards and other sympatric species.