Donini Valerio, Pedrotti Luca, Ferretti Francesco, Corlatti Luca
Stelvio National Park, Sustainable Development and Protected Areas Service Autonomous Province of Trento Cogolo di Pejo Italy.
Stelvio National Park Bormio Italy.
Ecol Evol. 2021 May 25;11(12):8264-8280. doi: 10.1002/ece3.7657. eCollection 2021 Jun.
Investigating the impact of ecological factors on sex- and age-specific vital rates is essential to understand animal population dynamics and detect the potential for interactions between sympatric species. We used block count data and autoregressive linear models to investigate variation in birth rate, kid survival, female survival, and male survival in a population of Alpine chamois monitored over 27 years within the Stelvio National Park, Central Italian Alps, as function of climatic variables, density dependence, and interspecific competition with red deer . We also used path analysis to assess the indirect effect of deer abundance on chamois growth rate mediated by each demographic parameter. Based on previous findings, we predicted that birth rate at [] would negatively relate to red deer abundance at year [ - 1]; survival rates between [] and [ + 1] would negatively relate to red deer abundance at year [ - 1] and to the interactive effect of winter precipitation at [ + 1] and chamois density at []. Our results showed that birth rate was positively related to spring-summer precipitation in the previous year, but this effect was hampered by increasing red deer abundance. Kid and female survival rates were negatively related to the combined effect of chamois abundance and winter precipitation. Male and female survival rates were negatively related to lagged red deer abundance. The path analysis supported a negative indirect effect of red deer abundance on chamois growth rate mediated by birth rate and female survival. Our results suggest that chamois population dynamics was largely explained by the synergistic effect of density dependence and winter harshness, as well as by interspecific competition with red deer, whose effects were seemingly stronger on the kid-female segment of the population.
研究生态因素对特定性别和年龄的生命率的影响，对于理解动物种群动态以及检测同域物种间相互作用的可能性至关重要。我们使用块状计数数据和自回归线性模型，研究了在意大利中部阿尔卑斯山的斯泰尔维奥国家公园内，长达27年监测的高山羚羊种群的出生率、幼崽存活率、雌性存活率和雄性存活率的变化，这些变化是气候变量、密度依赖性以及与马鹿的种间竞争的函数。我们还使用路径分析来评估鹿的数量通过每个人口统计学参数对羚羊生长率的间接影响。基于先前的研究结果，我们预测在[具体年份]的出生率将与前一年的马鹿数量呈负相关；在[具体年份]和[具体年份 + 1]之间的存活率将与前一年的马鹿数量以及[具体年份 + 1]的冬季降水量和[具体年份]的羚羊密度的交互作用呈负相关。我们的结果表明，出生率与上一年的春夏降水量呈正相关，但这种影响因马鹿数量的增加而受到阻碍。幼崽和雌性存活率与羚羊数量和冬季降水量的综合影响呈负相关。雄性和雌性存活率与滞后的马鹿数量呈负相关。路径分析支持了马鹿数量通过出生率和雌性存活率对羚羊生长率产生的负间接影响。我们的结果表明，羚羊种群动态在很大程度上是由密度依赖性和冬季严酷性的协同效应以及与马鹿的种间竞争所解释的，而这些影响在种群的幼崽 - 雌性部分似乎更强。
