Non-Metric Multidimensional Scaling ordination of fish species frequencies for FLOLIZ, NCS and DCS over the whole sampling period (2019–2022) at night (A) and during daytime (B). The stress value <0.20 corresponds to a good fit (Clarke, 1993). The non-metric fit R² of 0.98 for both and the linear fit R² of 0.92 and 0.88 respectively corresponds to a fairly good adjustment. The red stars (*) show a significant difference in the abundance of the corresponding species between the control stations (DCS, NCS) and the FLOLIZ (refer to Tab. 2).