The knowledge of fish behaviour within vertical slot fishways is limited. This paper describes fish progression through five pools of the 1:4 scale vertical slot fishway of the University of Poitiers (France). Fish behaviour is studied by video monitoring in the third pool of the model. The results are analyzed comparing the number of fish passages between the pools, the stabling zones used by fish in the monitoring pool during their progression and fish trajectories. Comparison of four different pool configurations is performed to estimate the effect of geometric variations on the upstream migration efficiency
