Lateral migration of Liposarcus anisitsi (Siluriformes, Loricariidae) in the Preto River, Alto Parana Basin, Brazil

The lateral migration carried out by the gray catfish Liposarcus anisitsi in the Preto River, northwestern region of the State of Sao Paulo, Brazil, is studied. The migratory movements are restricted to the transversal of the main axis of the river and depend on the seasonal environment variations which permit the use of four different biotopes during the species life cycle: main channel, bed river banks, temporary lagoons, permanent lagoons. The migration is essentially trophic and can to be associated with an alimentary strategy which favors the reduction of interspecific and intraspecific competition.