Tamario Carl, Tibblin Petter, Forsman Anders
Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, Umeå, Sweden.
Center for Ecology and Evolution in Microbial Model Systems, EEMiS, Department of Biology and Environmental Science, Linnaeus University, Kalmar, Sweden.
Proc Biol Sci. 2025 Jun;292(2049):20250429. doi: 10.1098/rspb.2025.0429. Epub 2025 Jun 18.
The spatial synchrony framework suggests that asynchrony among subpopulations in different branches of a river network should stabilize the metapopulation. However, how barriers affect this framework remains poorly understood. This is a significant knowledge gap given that population synchrony arises from dispersal and environmental similarity, both of which are influenced by barriers. We empirically evaluated how barriers impact fish population synchrony and, subsequently, the associations between synchrony and metapopulation persistence, productivity, stability and trajectory within fragments. We found that barriers demographically decouple populations by decreasing synchrony in brown trout () and Eurasian minnow (), but not in northern pike (), suggesting species-specific responses to fragmentation. Additionally, asynchrony had a stabilizing portfolio effect on metapopulation stability at the fragment level that was statistically significant for . Higher fragment synchrony also made and populations less stable. The impact of barriers on riverine fish population synchrony emphasizes the need to include barriers in future studies on the causes and consequences of synchrony in rivers. That asynchrony stabilizes populations in some riverine fishes suggests that conservation priorities should lie in restoring or retaining larger fragment sizes and higher branching complexity with intact connectivity.
空间同步框架表明，河网不同分支中的亚种群之间的异步性应能稳定集合种群。然而，障碍物如何影响这一框架仍知之甚少。鉴于种群同步性源于扩散和环境相似性，而这两者均受障碍物影响，这是一个重大的知识空白。我们通过实证评估了障碍物如何影响鱼类种群同步性，以及随后同步性与碎片内集合种群持续性、生产力、稳定性和轨迹之间的关联。我们发现，障碍物通过降低褐鳟（Salmo trutta）和欧亚米诺鱼（Phoxinus phoxinus）的同步性，在种群统计学上使种群解耦，但在白斑狗鱼（Esox lucius）中并非如此，这表明了对碎片化的物种特异性反应。此外，异步性对碎片水平上的集合种群稳定性具有稳定的组合效应，这对Salmo trutta具有统计学意义。更高的碎片同步性也使Salmo trutta和Phoxinus phoxinus种群的稳定性降低。障碍物对河流鱼类种群同步性的影响强调了在未来关于河流同步性的成因和后果的研究中纳入障碍物的必要性。异步性能稳定一些河流鱼类的种群，这表明保护重点应在于恢复或保留更大的碎片大小以及具有完整连通性的更高分支复杂性。
