Borzée Amaël, Andersen Desiree, Jang Yikweon
Laboratory of Behavioral Ecology and Evolution, School of Biological Sciences, Seoul National University, Seoul, South Korea.
Division of EcoScience, Ewha Women's University, Seoul, South Korea.
PeerJ. 2018 Sep 19;6:e5568. doi: 10.7717/peerj.5568. eCollection 2018.
Amphibian populations fluctuate naturally in size and range and large datasets are required to establish trends in species dynamics. To determine population trends for the endangered Suweon Treefrog (), we conducted aural surveys in 2015, 2016, and 2017 at each of 122 sites where the species was known to occur in the Republic of Korea. Despite being based on individual counts, the focus of this study was to establish population trends rather than population size estimates, and we found both environmental and landscape variables to be significant factors. Encroachment was also a key factor that influenced both the decreasing number of calling individuals and the negative population dynamics, represented here by the difference in the number of calling individuals between years. Generally, most sites displayed minimal differences in the number of calling males between years, although there was a large fluctuation in the number of individuals at some sites. Finally, when adjusted for the overall population size difference between years, we found the population size to be decreasing between 2015 and 2017, with a significant decrease in the number of calling individuals at specific sites. High rate of encroachment was the principal explanatory factor behind these marked negative peaks in population dynamics.
两栖动物的种群数量和分布范围会自然波动，需要大量数据集来确定物种动态趋势。为了确定濒危的水原树蛙（）的种群趋势，我们于2015年、2016年和2017年在韩国已知该物种出现的122个地点中的每一个进行了听觉调查。尽管本研究基于个体计数，但重点是确定种群趋势而非估计种群规模，并且我们发现环境和景观变量都是重要因素。栖息地侵占也是一个关键因素，它既影响了鸣叫个体数量的减少，也影响了种群的负增长动态，这里用年份间鸣叫个体数量的差异来表示。总体而言，大多数地点年份间鸣叫雄性数量差异最小，尽管有些地点个体数量波动较大。最后，在对年份间总体种群规模差异进行调整后，我们发现2015年至2017年种群规模在下降，特定地点鸣叫个体数量显著减少。高栖息地侵占率是这些种群动态中明显负峰值背后的主要解释因素。
