Division of Biosphere Science, Graduate School of Environmental Science, Hokkaido University, Sapporo, Hokkaido 060-0809, Japan.
Fish Physiol Biochem. 2011 Jun;37(2):273-84. doi: 10.1007/s10695-011-9495-y. Epub 2011 May 11.
The movements of 28 adult chum salmon, Oncorhynchus keta (Walbaum) tagged with electromyogram (EMG) transmitters were tracked along the Toyohira river, Hokkaido, Japan, in October of 2007 and 2008 to investigate and evaluate the upstream migratory behavior through the protection bed and fishway of ground sills. The approach time of fish that ascended successfully through the protection bed and fishway was shorter than that of unsuccessful fish. The unsuccessful fish were observed to swim in currents with high water velocity and shallow water depth at swimming speeds that exceeded their critical swimming speed (U (crit)) during the approach to these structures. In consequence, unsuccessful fish frequently alternated between burst and maximum sustained speeds without ever ascending the fishway, and eventually became exhausted. It is important that fishway are constructed to enable chum salmon to find a passage way easily, so that they can migrate upstream rapidly without wasting excessive energy.
2007 年和 2008 年 10 月，在日本北海道的丰平川，我们使用肌电图（EMG）发射器标记了 28 条成年大麻哈鱼，对它们的洄游运动进行了跟踪，以调查和评估通过保护床和鱼梯的底坎式鱼道的洄游行为。成功通过保护床和鱼梯的鱼的接近时间短于不成功的鱼。在接近这些结构时，我们观察到不成功的鱼在水流速度高、水深浅的情况下游泳，其游泳速度超过了临界游泳速度（U(crit)）。因此，不成功的鱼在没有进入鱼道的情况下，频繁地在爆发速度和最大持续速度之间切换，最终筋疲力尽。重要的是，鱼道的建造应使大麻哈鱼能够轻松找到洄游通道，以便它们能够快速洄游上游，而不会浪费过多的能量。
