The article highlights a significant initiative by the Ministry of Agriculture to document the impact of marine reserves on commercial fish populations in the Western Mediterranean. This initiative, funded by the European Maritime and Fisheries Fund from 2016 to 2020, has resulted in the largest historical series of data on this topic. The data, collected through scuba visual censuses, focuses on the abundance and biomass of vulnerable fish species, their specific richness and size composition, and a comparison of diversity indices within and outside the reserves. The project has covered various areas, aiming to demonstrate the effectiveness of fishing effort reduction measures in aiding fish population recovery.