This work aims to investigate freshwater fish exploitation status in three Tunisian reservoirs: Siliana, Lahjar and Kasseb associated with the examination of progress in the zoo-sanitary registration. Three types of operators at these reservoirs were identified: a promoter, a fishery development group, and independent fishermen. The only operator who has all the required documents for the zoo-sanitary registration, is the promoter operating at Lahjar Reservoir. The SWOT analysis applied to Siliana, Lahjar and Kasseb reservoirs allowed us to highlight the differences between the three modes of exploitation and to identify their strengths and weaknesses. Along with these findings, the analysis revealed factors that may directly or indirectly affect the reservoirs and made it possible to elaborate new perspectives which would help improve the inland fish farming sector in Tunisia.

To monitor and assess the state of Tunisian freshwater fisheries, two surveys were undertaken at Ghezala and Lahjar reservoirs. Samples were taken in April and May 2013, a period when the fish catchability is high. The selected reservoirs have different surface areas and bathymetries. Using multi-mesh gill nets (EN 14575 amended) designed for sampling fish in lakes, standard fishing methods were applied to estimate species composition, abundance, biomass, and size distribution. Four species were caught in the two reservoirs: barbel, mullet, pike-perch, and roach. Fish abundance showed significant change according to sampling sites, depth strata, and the different mesh sizes used. From the reservoir to the tributary, it was concluded that fish biomass distribution was governed by depth and was most abundant in the upper water layers. Species size distribution differed significantly between the two reservoirs, exceeding the length at first maturity. Species composition and abundance were greater in Lahjar reservoir than in Ghezala. Both reservoirs require support actions to improve fish productivity.

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