Bonardi Anna, Corlatti Luca, Bragalanti Natalia, Pedrotti Luca
Stelvio National Park, Bormio, Italy.
Institute of Wildlife Biology and Game Management, University of Natural Resources and Life Sciences Vienna, Vienna, Austria.
Integr Zool. 2017 Jan;12(1):61-76. doi: 10.1111/1749-4877.12237.
The dynamics of red deer Cervus elaphus populations has been investigated across different environmental conditions, with the notable exception of the European Alps. Although the population dynamics of mountain-dwelling ungulates is typically influenced by the interaction between winter severity and density, the increase of temperatures and the reduction of snowpack occurring on the Alps since the 1980s may be expected to alter this pattern, especially in populations dwelling at medium - low elevations. Taking advantage of a 29-year time series of spring count data, we explored the role of weather stochasticity and density dependence on growth rate and vital rates (mortality and weaning success), and the density-dependent variation in body mass in a red deer population of the Italian Alps. The interaction between increasing values of density and snow depth exerted negative and positive effects on growth and mortality rates, respectively, while weaning success was negatively affected by increasing values of density, female-biased sex ratio and snow depth. Body mass of males and females of different age classes declined as population size increased. Our data support the role of winter severity and density dependence as key components of red deer population dynamics, and provide insight into the species' ecology on the European Alps. Despite the recent decline of snowpack on the Alpine Region, the negative impacts of winter severity and population abundance on growth rrate (possibly mediated by the density-dependent decline in body mass) confirms the importance of overwinter mortality in affecting the population dynamics of Alpine-dwelling red deer.
人们已经在不同环境条件下对马鹿（Cervus elaphus）种群动态进行了研究，但欧洲阿尔卑斯山是个明显的例外。尽管山地有蹄类动物的种群动态通常受冬季严酷程度和种群密度之间相互作用的影响，但自20世纪80年代以来阿尔卑斯山出现的气温升高和积雪减少情况，可能会改变这种模式，尤其是在中低海拔地区的种群中。利用长达29年的春季计数数据时间序列，我们探究了天气随机性和密度依赖性对意大利阿尔卑斯山一个马鹿种群的增长率和生命率（死亡率和断奶成功率）的作用，以及体重的密度依赖性变化。密度值增加与积雪深度之间的相互作用分别对增长率和死亡率产生了负面和正面影响，而断奶成功率则受到密度值增加、偏雌性的性别比例和积雪深度的负面影响。随着种群规模的增加，不同年龄组雄性和雌性的体重都有所下降。我们的数据支持了冬季严酷程度和密度依赖性作为马鹿种群动态关键组成部分的作用，并为该物种在欧洲阿尔卑斯山的生态学提供了见解。尽管阿尔卑斯地区近期积雪减少，但冬季严酷程度和种群数量对增长率的负面影响（可能由体重的密度依赖性下降介导）证实了越冬死亡率在影响阿尔卑斯山马鹿种群动态方面的重要性。
