UMR 5558, Biométrie et Biologie Evolutive, Université Claude Bernard Lyon 1, 43 boulevard du 11 novembre 1918, Villeurbanne Cedex, France.
Ecol Lett. 2013 May;16 Suppl 1:48-57. doi: 10.1111/ele.12059. Epub 2013 Jan 9.
How populations respond to climate change depends on the interplay between life history, resource availability, and the intensity of the change. Roe deer are income breeders, with high levels of allocation to reproduction, and are hence strongly constrained by the availability of high quality resources during spring. We investigated how recent climate change has influenced demographic processes in two populations of this widespread species. Spring began increasingly earlier over the study, allowing us to identify 2 periods with contrasting onset of spring. Both populations grew more slowly when spring was early. As expected for a long-lived and iteroparous species, adult survival had the greatest potential impact on population growth. Using perturbation analyses, we measured the relative contribution of the demographic parameters to observed variation in population growth, both within and between periods and populations. Within periods, the identity of the critical parameter depended on the variance in growth rate, but variation in recruitment was the main driver of observed demographic change between periods of contrasting spring earliness. Our results indicate that roe deer in forest habitats cannot currently cope with increasingly early springs. We hypothesise that they should shift their distribution to richer, more heterogeneous landscapes to offset energetic requirements during the critical rearing stage.
种群对气候变化的响应取决于生活史、资源可利用性和变化强度之间的相互作用。马鹿是收入繁殖者,具有高水平的繁殖分配,因此在春季高质量资源的可利用性方面受到强烈限制。我们研究了最近的气候变化如何影响这种广泛分布物种的两个种群的人口过程。在研究过程中,春季开始得越来越早,这使我们能够确定具有不同春季开始时间的两个时期。当春天来得早时,两个种群的生长速度都变慢了。正如一个长寿和多次生殖的物种所预期的那样,成年个体的存活率对种群增长有最大的潜在影响。利用扰动向分析,我们测量了人口增长的变化中,在两个时期和种群内,各参数的相对贡献。在各时期内,关键参数的身份取决于增长率的变化,但在不同的早期春天之间的时期,变化的招募是观察到的人口变化的主要驱动因素。我们的研究结果表明,森林生境中的马鹿目前无法应对越来越早的春天。我们假设它们应该将其分布转移到更丰富、更异质的景观中,以抵消在关键饲养阶段的能量需求。