Diversidade e padrões de distribuição de peixes não-nativos da Bacia do Alto Rio Paraná

Abstract

The upper Paraná River basin, the second largest river basin in Brazil, includes sub basins that drain the states of Goiás, Minas Gerais, São Paulo, Mato Grosso do Sul, Paraná and the Federal District. Located in the most developed and anthropized region of South America, the basin is impacted by agricultural, industrial and livestock activities, in addition to the presence of hydroelectric plants, which act as routes for the introduction of non-native fish species. Other mechanisms of introduction include aquarium keeping practices, the use of live bait in fishing, diversion systems, aquaculture and connections with other basins, such as the Tocantins-Araguaia River, although details of this last route are not yet fully clarified. Currently, the upper Paraná River basin is home to 133 non-native fish species, of which five are hybrids, distributed in 14 orders and 35 families. Over the past two centuries, the number of introductions influenced by human activities has increased exponentially and, as a result, there are few habitats that remain free of the presence of non-native species. In the Paraná basin, the construction of Itaipu is the largest entry route for non-native species, followed by aquaculture. It is estimated that the upper Paraná basin will be home to 180 non-native species and that by 2078 all species will have been catalogued.