Poster 14: Fish fauna of reservoir lakes in the Walloon region

Within the framework of a study of the spatio-temporal distribution of fish populations in reservoir lakes, we carried out a review of the current knowledge on fish stocks in reservoirs of the Walloon region. We analysed results of gillnet fishing catches organised during the 1990's in these lakes and noticed that knowledge remains extremely scattered. For 5 lakes out of 15, there have not yet been any exploratory fishing, whereas for 7 lakes a limited number of campaigns give some indications on species diversity, abundance and relative biomass. Only the lakes of Robertville and Bütgenbach have been regularly assessed since 1994, within the framework of the follow-up of the introduction of two coregonid species. Species diversity generally remains relativy low. Only common and tolerant species (Alburnus alburnus L., Rutilus rutilus L., Abramis brama L., Perca fluviatilis L. …) are well represented. Knowledge of the structure of fish communities, and their relation with the abiotic and biotic conditions of artificial lakes, should be improved in order to use these environments sustainably.