Ferretti Francesco, Lovari Sandro
Research Unit of Behavioural Ecology, Ethology and Wildlife Management-Department of Life Sciences, University of Siena, Via P.A. Mattioli 4, 53100 Siena, Italy; Ev-K2-CNR, Via San Bernardino 145, 24126 Bergamo, Italy.
Research Unit of Behavioural Ecology, Ethology and Wildlife Management-Department of Life Sciences, University of Siena, Via P.A. Mattioli 4, 53100 Siena, Italy; Ev-K2-CNR, Via San Bernardino 145, 24126 Bergamo, Italy.
Behav Processes. 2016 Aug;129:101-104. doi: 10.1016/j.beproc.2016.06.008. Epub 2016 Jun 14.
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. 200m 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.
温度变化预计会影响山区食草动物的海拔迁移，进而影响其捕食者的海拔迁移，但相关信息却很匮乏。我们连续五年（2006 - 2010年）评估了喜马拉雅中部一个地区温度与一种大型山地食草动物喜马拉雅塔尔羊（Hemitragus jemlahicus）及其主要捕食者雪豹（Panthera uncia）所使用海拔之间的月度关系。与预期相反，塔尔羊目击地点的海拔与温度之间没有显著的直接关系。在我们整个研究过程中，塔尔羊目击地点的平均海拔下降了约200米。正如预期的那样，雪豹的活动轨迹与塔尔羊一致，尽管雪豹的核心活动区域并未向下移动。塔尔羊仍然是雪豹的主要食物来源：我们认为前者没有因温度升高而向上迁移以避免与后者相遇。避免在较低海拔与体型更大的豹（Panthera pardus）竞争，可能解释了雪豹为何没有将其核心活动区域向下转移。显然，种间相互作用（捕食；竞争）对喜马拉雅塔尔羊和雪豹活动的影响大于气候变化。
