The water district of Massaciuccoli is an eu- trophic coastal basin, located in Tuscany (central Italy) in the provinces of Lucca and Pisa and includes the lake, marsh and reclaimed areas with their drainage channels (Chelucci, 2005). The average depth of the lake is 2.5 meters, with a variation of 90 cm between the dry summer season and the rainy winter. The average pH of the water is 8.2, and the average temperature ranges from 7°C in winter to 22°C in summer (Spandre et al., 1997). In the last century the fish fauna reflected a progressive increase in introduced species, which tend to be very resist- ant (Gozlan et al., 2010), to the disadvantage of the species that evolutionarily originated in the basin (Alessio et al., 1992)