Inventário da ictiofauna do baixo rio dourados, bacia do Alto Paraná, Brasil

Abstract

The Dourados River is a place that needs studies, especially on the fish species that inhabit it. Thus, the objective of the study was to investigate the fish fauna of the stretch of lower Dourados River, located in the Upper Paraná River basin, carrying out an inventory of the fish species present in this location and their respective abundances, in order to contribute to conservation studies of these species. For this, four collections were carried out in two different sampling sites (channels and artificial tanks at the Jangadeiro fishing site in Fátima do Sul, MS - C1, C2 and C4, in addition to a flooded region of the Dourados river close to the eighth line towards Vicentina, MS - C3), over the course of a year, including flood and dry seasons, in addition to different fishing gear. The individuals were anesthetized with eugenol solution, fixed in 10% formaldehyde and stored in 70% alcohol. The taxonomic identification of the species was carried out based on specialized literature and assistance from experts. A total of 2,069 individuals were captured, belonging to four orders, 15 families, and 43 species, from which 13 are not native to the Upper Paraná River basin. The collection that presented the greatest richness was collection 4, and collection 3 presented the lowest richness, being the only one carried out in a different location from the others, with less sampling effort. Characiformes was the most representative order, presenting the highest occurrence of the species Serrapinnus notomelas and Psellogrammus kennedyi, the second order with the highest occurrence was Siluriformes. The presence of invasive species highlights the need for management and conservation measures. This survey provides unprecedented and essential information for understanding local biodiversity and can support conservation and management strategies for water and fishing resources in the region.