Rio São José dos Dourados is a river system located in the northwestern region of São Paulo state, Brazil, draining into the upper Paraná basin. The river and its tributaries flow through a landscape that is predominantly agricultural, with roughly three-quarters of the surrounding land used for pasture. Despite this heavy land use, the main river and many of its tributary reaches maintain good physicochemical water quality, supporting a diverse and ecologically interesting fish community. The system is part of the broader upper Paraná drainage, one of South America's most ichthyologically rich river basins, and offers anglers the chance to pursue a variety of native tropical species in a setting that blends open pastureland with riparian corridors.