Relationship between Upstream Swimming Behaviors of Juvenile Grass Carp and Characteristic Hydraulic Conditions of a Vertical Slot Fishway

The successful fish upstream movement through a dam/gate is closely associated with the hydraulic conditions of fishway. To improve passage efficiency, this study investigated swimming behaviors juvenile grass carp, representative four major Chinese carps, under characteristic designed vertical slot fishway model. impacts different discharges and baffle lead angles on test were analyzed, selection trajectory was studied overlay their trajectories water flow field resulting from numerical modeling. We found that same discharge, percentage angle 45° higher than 60° 30°. Within fixed angle, lower movement. During movement, had preferred velocity 0.01–0.45 m/s in pool, avoided areas where turbulence kinetic energy (TKE) greater 0.012 m2/s2. These results provide basis for design fishways reference studying other species.