SWIMMING BEHAVIOR OF Tribolodon hakonensis IN A ROCKY RAMP FISHWAY WITH TRANSVERSE SLOPE THAT CHANGED ROUGHNESS HEIGHT

In this study, authors carried out some experiments those using immature fish; Tribolodon hakonensis which had low swimming capability in a rocky ramp fishway with transverse slope. As the results, in Case2 b, run-up ratio Rr decreased 10 ~ 30 % in comparison with Case2 a where had high swimming capability of the fish. Therefore, invention to form a variety of flows regardless of small and large of the flow quantity is necessary. In Case3, a variety of flows was formed by securing of water depth regardless of small and large of the flow quantity. Moreover, run-up ratio Rr became more than 60(%) even if swimming capability of the fish was low. In addition, fish run up at the point which was 4 BL ~ 7 BL (cm/s) in these experiments.