Dyck Marissa A, Iosif Ruben, Promberger-Fürpass Barbara, Popescu Viorel D
School of Environmental Studies University of Victoria Victoria British Columbia Canada.
Foundation Conservation Carpathia Brașov Romania.
Ecol Evol. 2025 Apr 25;15(4):e71381. doi: 10.1002/ece3.71381. eCollection 2025 Apr.
Interspecific interactions play a central role in structuring animal communities and food webs. In particular, carnivores are important topdown regulators in ecological communities and the loss of carnivore species can have devastating ecosystem effects. Similarly, carnivore reintroductions are successful if the prey base is sufficient to support population growth, making the case for the importance of bottom-up regulation processes. As such, rewilding efforts targeted at restoring food webs and natural community regulation processes (trophic rewilding) have become increasingly popular. However, investigations of regulation processes in terrestrial vertebrate communities often take place in heavily altered systems, potentially biasing inference on the presence or importance of top-down versus bottom-up regulation processes. Here, we use a stable mammalian assemblage in the Romanian Carpathians to evaluate the relative importance of top-down and bottom-up processes and provide a benchmark for understanding the effects and the success of rewilding initiatives. To do so, we used camera trap data from two consecutive years in the Southern Romanian Carpathians and developed hypothesisbased interaction pathways for top-down and bottom-up regulation in a piecewise structural equation modeling (SEM) framework. Results from SEMs indicate that while both top-down (wolf and Eurasian lynx-driven) and bottom-up processes (driven by roe deer, red deer, wild boar and hare abundance) play important roles in shaping community structure, landscape characteristics (i.e., terrain ruggedness, road density, elevation, and forest cover) have a greater effect on both predators and prey. The results of this research have implications for rewilding efforts in Europe and globally. This study highlights the importance of preserving natural habitats, underscoring that effective species conservation and coexistence must go hand in hand with conserving natural spaces.
种间相互作用在构建动物群落和食物网中起着核心作用。特别是，食肉动物是生态群落中重要的自上而下的调节者，食肉动物物种的丧失可能会对生态系统产生毁灭性影响。同样，如果猎物基数足以支持种群增长，食肉动物的重新引入就是成功的，这说明了自下而上调节过程的重要性。因此，旨在恢复食物网和自然群落调节过程（营养重归野生状态）的野化努力越来越受欢迎。然而，对陆地脊椎动物群落调节过程的研究通常是在受到严重改变的系统中进行的，这可能会使关于自上而下与自下而上调节过程的存在或重要性的推断产生偏差。在这里，我们利用罗马尼亚喀尔巴阡山脉中一个稳定的哺乳动物组合来评估自上而下和自下而上过程的相对重要性，并为理解野化举措的效果和成功提供一个基准。为此，我们使用了罗马尼亚南部喀尔巴阡山脉连续两年的相机陷阱数据，并在分段结构方程模型（SEM）框架中为自上而下和自下而上的调节建立了基于假设的相互作用路径。结构方程模型的结果表明，虽然自上而下（由狼和欧亚猞猁驱动）和自下而上的过程（由狍、马鹿、野猪和野兔的数量驱动）在塑造群落结构中都发挥着重要作用，但景观特征（即地形崎岖度、道路密度、海拔和森林覆盖）对捕食者和猎物都有更大的影响。这项研究的结果对欧洲和全球的野化努力都有启示。这项研究强调了保护自然栖息地的重要性，强调有效的物种保护和共存必须与保护自然空间齐头并进。
