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Ferretti, F., Lovari, S. (2016). Predation may counteract climatic change as a driving force for movements of mountain ungulates.
Abstract: Temperature variations are expected to influence altitudinal movements of mountain herbivores and, in
turn, those of their predators, but relevant information is scarce. We evaluated monthly relationships
between temperature and altitude used by a large mountain-dwelling herbivore, the Himalayan tahr
Hemitragus jemlahicus, and its main predator, the snow leopard Panthera uncia, in an area of central
Himalaya for five consecutive years (2006–2010). In contrast to expectations, there was no significant
direct relationship between altitude of tahr sightings and temperature. The mean altitude of tahr sightings
decreased by c. 200 m throughout our study. As expected, snow leopard movements tracked those of tahr,
although the core area of the snow leopard did not move downwards. Tahr remained the staple of the
snow leopard diet: we suggest that the former did not move upwards in reaction to higher temperature
to avoid encounters with the latter. Avoidance of competition with the larger common leopard Panthera
pardus at lower altitudes could explain why snow leopards did not shift their core area downwards.
Apparently, interspecific interactions (predation; competition) influenced movements of Himalayan tahr
and snow leopards more than climatic variations.
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Li, J., McCarthy, T. M., Wang, H., Weckworth, B. V., Shaller, G. B., Mishra, C., Lu, Z., Beissinger, S. R. (2016). Climate refugia of snow leopards in High Asia. Biological Conservation, (203), 188–196.
Abstract: Rapidwarming in High Asia is threatening its unique ecosystemand 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.
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