Fishes of the southeastern Brazil Atlantic Forest

Abstract

The largest preserved areas of Atlantic Forest are located in the southeastern region of Brazil. Estuaries, mangroves, rivers and streams are home to a community of fish that is still poorly understood. The composition of fish species and their relationships with environmental conditions were used to identify homogeneous areas within a landscape of 33,000 km2. A total of 6,542 specimens, representing 124 species and 13 orders of bony fishes were collected at 102 sampling stations. Resulting scores from a canonical correspondence analysis applied to biological and environmental data were used in a cluster analysis to identify fish species with similar spatial distributions and localities with similar fish fauna and abiotic conditions. Five micro-regions were identified, with homogeneous compositions of species, allowing better planning of conservation of aquatic biodiversity. Despite a high degree of preservation, impacts due to deforestation, drainage of wetlands and overfishing were detected, as well as the introduction of 41 exotic species.