Bærum Kim M, Silva Ana T, Baktoft Henrik, Gjelland Karl Ø, Økland Finn, Forseth Torbjørn
Norwegian Institute for Nature Research, Fakkelgården, 2624, Lillehammer, Norway.
Norwegian Institute for Nature Research, Postbox 5685, 7485, Trondheim, Norway.
Sci Rep. 2024 Dec 28;14(1):30778. doi: 10.1038/s41598-024-80972-4.
The Atlantic salmon (Salmo salar) is an iconic species of significant ecological and economic importance. Their downstream migration as smolts represents a critical life-history stage that exposes them to numerous challenges, including passage through hydropower plants. Understanding and predicting fine-scale movement patterns of smolts near hydropower plants is therefore essential for adaptive and effective management and conservation of this species. We present a spatially explicit individual-based model for predicting the movement of Atlantic salmon smolts in regulated rivers in Norway, parameterised for smolt movements in the River Mandal and the River Orkla. The model is rooted in statistically derived relationships between observed smolt swimming behaviour and the hydraulic variables they encounter. The aim of the model was to provide fast yet representative swimming patterns past hydropower plants, based on the hydraulic conditions experienced by the smolts. The model outperformed a 'drift-only' model in portraying observed swim tracks when comparing simulated and observed tracks. It was found to represent smolt swimming behaviour well. Our results show that by constructing swim models using relatively simple and general statistical relationships between smolt swimming behaviour and the hydraulic environment, we can produce fast and relevant outputs for an adaptive management process, aimed at exploring how physical implementations or changes in flow regulations might affect smolt populations.
大西洋鲑（Salmo salar）是一种具有重要生态和经济意义的标志性物种。它们作为幼鲑向下游洄游是一个关键的生命史阶段，在此过程中它们面临诸多挑战，包括通过水电站。因此，了解和预测水电站附近幼鲑的精细运动模式对于该物种的适应性和有效管理及保护至关重要。我们提出了一个基于个体的空间明确模型，用于预测挪威受调控河流中大西洋鲑幼鲑的运动，并针对曼达尔河和奥尔克拉河的幼鲑运动进行了参数化。该模型基于观测到的幼鲑游泳行为与其所遇到的水力变量之间的统计关系。该模型的目的是根据幼鲑所经历的水力条件，提供经过水电站的快速且具有代表性的游泳模式。在比较模拟轨迹和观测轨迹时，该模型在描绘观测到的游泳轨迹方面优于“仅漂流”模型。结果表明它能很好地代表幼鲑的游泳行为。我们的结果表明，通过利用幼鲑游泳行为与水力环境之间相对简单且通用的统计关系构建游泳模型，我们可以为适应性管理过程生成快速且相关的输出，旨在探索物理设施或流量调控变化如何可能影响幼鲑种群。
