Canadian Journal of Fisheries and Aquatic Sciences, Ahead of Print.
Dispersal and shared environmental conditions can both synchronize the dynamics of local populations, but disentangling their relative influence on dynamics is challenging. We used a Bayesian approach to estimate the synchrony of a metapopulation of Atlantic salmon (Salmo salar) composed of 18 populations in Brittany, France, including a 24-year time series of the abundances of juveniles. We estimated the spatial synchrony at a regional and local spatial scale over the study period. We found a strong regional synchrony despite spatiotemporal variability of local synchrony in the abundance of juveniles. We then explored the drivers of synchrony, including environmental conditions (aspects of river flow) and abundance of adult breeders. This revealed that summer low-flow conditions seemed to synchronize the abundances of juveniles more than the synchrony in the abundance of adult breeders, suggesting a Moran effect. Given that drought conditions are expected to become more common with climate change, our work highlights the potentially strong synchronizing effect of summer low flow on the dynamics of local salmon populations and the benefits of considering synchrony at multiple scales.

中文翻译：

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大西洋鲑幼鱼种群动态的同步性：分析时空变化以及河流流量和人口学的影响

加拿大渔业和水生科学杂志，印刷前。
分散和共享的环境条件都可以同步当地人口的动态，但解开它们对动态的相对影响是具有挑战性的。我们使用贝叶斯方法来估计由法国布列塔尼的 18 个种群组成的大西洋鲑 (Salmo salar) 集合种群的同步性，包括 24 年的幼鱼丰度时间序列。我们估计了研究期间区域和局部空间尺度的空间同步性。尽管在大量幼鱼中局部同步存在时空变异性，但我们发现了强烈的区域同步。然后，我们探索了同步的驱动因素，包括环境条件（河流流量方面）和成年育种者的数量。这表明夏季低流量条件似乎使幼体的丰度比成年育种者的丰度同步更多，这表明莫兰效应。鉴于预计干旱条件将随着气候变化而变得更加普遍，我们的工作强调了夏季低流量对当地鲑鱼种群动态的潜在强大同步效应以及在多个尺度上考虑同步的好处。