<p>The sensor fish is an innovative measuring device that can record the physical forces experienced by fish during hydropower plant passage under real operating conditions. Collision events, pressure changes, shear forces and turbulence that occur in turbines or alternative bypasses can be measured and quantified during operation. This enables a standardized comparison between different operation modes, turbine types and hydropower plants. By linking the sensor fish data with the tolerance levels of different fish species to physical stressors, conclusions can be drawn regarding the potential effects of turbine or bypass passage on fish. This enables the identification of less harmful turbine types, operation modes and alternative bypasses for downstream passing fish, which can contribute to improving fish protection at hydropower plants. However, when interpreting the potential effects of physical stressors on fish, it must be considered that the tolerance levels for strike, decompression and shear forces for species native to Central Europe are not yet established and further research is consequently required.</p>