Department of Biological Sciences, University of Alabama, Tuscaloosa, AL, 35487, USA.
Department of Fish and Wildlife Conservation, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, USA.
Oecologia. 2020 Aug;193(4):889-901. doi: 10.1007/s00442-020-04731-8. Epub 2020 Aug 17.
Amphibian life history traits are affected by temperature and precipitation. Yet, connecting these relationships to population growth, especially for multiple populations within a species, is lacking and precludes our understanding of amphibian population dynamics and distributions. Therefore, we constructed integral projection models for five populations along an elevational gradient to determine how climate and season affect population growth of a terrestrial salamander Plethodon montanus and the importance of demographic vital rates to population growth under varying climate scenarios. We found that population growth was typically higher at the highest elevation compared to the lower elevations, whereas varying inactive season conditions, represented by the late fall, winter and early spring, produced a greater variation in population growth than varying active season conditions (late spring, summer, and early fall). Furthermore, survival and growth were consistently more important, as measured by elasticity, compared to fecundity, and large females had the greatest elasticity compared to all other body sizes. Our results suggest that changing inactive season conditions, especially those that would affect the survival of large individuals, may have the greatest impact on population growth. We recommend future experimental studies focus on the inactive season to better elucidate the mechanisms by which these conditions can affect survival.
两栖动物的生活史特征受温度和降水的影响。然而，将这些关系与种群增长联系起来，特别是对于物种内的多个种群，还缺乏相关研究，这阻碍了我们对两栖动物种群动态和分布的理解。因此，我们构建了沿海拔梯度的五个种群的整体预测模型，以确定气候和季节如何影响陆生蝾螈 Plethodon montanus 的种群增长，以及在不同气候情景下，人口增长对人口增长的重要性。我们发现，与低海拔地区相比，高海拔地区的种群增长通常更高，而不同的休眠季节条件（代表晚秋、冬季和早春）比不同的活跃季节条件（晚春、夏季和初秋）产生更大的种群增长变化。此外，与繁殖力相比，存活率和生长率的弹性更大，与所有其他体型相比，大个体的弹性最大。我们的研究结果表明，休眠季节条件的变化，特别是那些可能影响大个体生存的条件的变化，可能对种群增长产生最大影响。我们建议未来的实验研究集中在休眠季节，以更好地阐明这些条件如何影响生存的机制。
