Reproduction of a fish assemblage in the state of São Paulo, southeastern Brazil.

Fish reproductions were studied in two river basins (Corumbataí and Jacaré-Pepira basins) in the State of São Paulo, southeastern Brazil. In the Corumbataí basin, four sites were sampled: Cabeça River, Lapa Stream, Passa-Cinco River, and Corumbataí River; in the Jacaré-Pepira basin, three sites were sampled: Tamanduá Stream, Jacaré-Pepira River, and Agua Branca Stream. A total of 12 bimonthly samples were made. Fish equipment included gill nets, purse seines, sieves, and traps. The main objective of this study was to characterize the fish assemblage regarding their reproductive biology and to compare these reproductive traits between both river basins. Most individuals with gonads in stage C (mature) and in stage D (empty gonads) were captured in the spring and summer. Multiple spawn and parental care were common strategies, which guaranteed offspring survivorship in unstable conditions.