Migration from fresh water to the marine environment is a crucial, transitional stage in the development of Atlantic salmon (Salmo salar). This study used a combination of acoustic tracking, instrument data, and hydrodynamic modelling to examine behaviour of juvenile salmon (smolts) during their transition from fresh water to the marine environment. The study focuses on a high-energy coastal environment in northern Scotland, which is currently being developed for renewable energy extraction and where there is potential for negative impacts on salmon with energy extraction devices and structures. Thirty-four smolts were captured in the River Wick in Caithness and tagged with acoustic tags transmitting at 69 kHz. The Telemac–Mascaret modelling suite was utilized to construct a three-dimensional model of the study area and surrounding waters to estimate smolt-current interactions during detection times. Timing of migration was linked to low-light conditions, with smolts mainly exiting the river at night and when the moon was below the horizon. The movement of most of the tags conformed with modelled tidal currents and the tracks matched modelled marine tidal patterns. Smolts were detected only on a single tide suggesting that they rapidly cleared the vicinity of the receiver array.

中文翻译：

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结合声学跟踪和水动力模型研究大西洋鲑鱼 (Salmo salar) 鲑鱼进入高能沿海水域时的洄游行为

从淡水迁移到海洋环境是大西洋鲑鱼（Salmo salar）发育的关键过渡阶段。这项研究结合了声学跟踪、仪器数据和流体动力学模型来检查幼年鲑鱼 (smolts) 在从淡水环境过渡到海洋环境期间的行为。该研究侧重于苏格兰北部的高能沿海环境，该环境目前正在开发用于可再生能源提取，并且能源提取装置和结构可能对鲑鱼产生负面影响。在凯斯内斯的威克河中捕获了 34 条小鲑鱼，并用 69 kHz 的声学标签进行了标记。Telemac-Mascaret 建模套件用于构建研究区域和周围水域的 3D 模型，以估计检测时间内的 smolt-current 相互作用。迁移的时间与光线不足的条件有关，小鲑鱼主要在夜间和月亮在地平线以下时离开河流。大多数标签的运动符合模拟的潮流，并且轨迹与模拟的海洋潮汐模式相匹配。仅在一次潮汐中检测到 Smolts，这表明它们迅速清除了接收器阵列附近。大多数标签的运动符合模拟的潮流，并且轨迹与模拟的海洋潮汐模式相匹配。仅在一次潮汐中检测到 Smolts，这表明它们迅速清除了接收器阵列附近。大多数标签的运动符合模拟的潮流，并且轨迹与模拟的海洋潮汐模式相匹配。仅在一次潮汐中检测到 Smolts，这表明它们迅速清除了接收器阵列附近。