The aim of this work was to characterize the fish farming in the Ribeira de Iguape Basin, southern São Paulo State (Brazil), in relation to the management systems. Forty two farms were studied. A semi-intensive system is used by 36 farmers, while an intensive system is used only by 6 studied farmers. Their objectives were raising fish, juvenile fish production and sportive fishery. Forty one fish species were found to be cultivated, but only six were native species from Ribeira Valley: lambari (Astyanax sp Linneaus, 1758), traíra (Hoplias malabaricus Bloch, 1794), robalo (Centropomus ssp Cuvier and Valenciennes, 1928), jundiá (Rhamdia quelen Quoy and Gaimard, 1824), cascudo (Hypostomus sp Marschall, 1873) and cará (Geophagus brasiliensis Quoy and Gaimard, 1824). Fish escapes were observed in 95% of farms studied, with Nile tilapia (Oreocrhomis niloticus Linneaus, 1758) being the most frequent. The pacu (Piaractus mesopotamicus Halmberg, 1887) and Nile tilapia were the most cultivated species. According to estimation of food conversion, around 32% of food supplied was wasted yearly. The fish farming is an activity in expansion in the Ribeira Valley and account for the second regional economic activity after banana cultivation.
fish farming; cultivated species; introduced species
