Establishment of non-native predator (Pisces, Erythrinidae) in a tributary of the Upper Paraná River basin, south Brazil

Ângela Teresa Silva-Souza,Marina Carmona Hernandes,Diego Azevedo Zoccal Garcia,Mário Luís Orsi

doi:10.4013/nbc.2015.103.08

Abstract

Erythrinus erythrinus is an erythrinid native from the basins of the Amazon, Orinoco, coastal rivers of the Guyana and Lower Parana, but allochthonous of Tibagi River region, Paranapanema basin. In the present work, we report the occurrence of E. erythrinus in Agua dos Tigres and Taquari rivers, in the Paranapanema basin, and aim to verify the occurrence of constancy and the condition of health of its specimens in sub-tributaries of the Lower Paranapanema River. The catch-per-unit-effort of the Agua dos Tigres River mouth was about three times higher than the site upstream of the same river, and the Taquari River presented the lowest value. The species presented constancy of catches in tributaries of the basin, where isometric growth and good health condition of the specimens were observed. Its introduction into the Tibagi River basin may have occurred due to an intentional release as remaining live bait discarded in commercial fishery operations or may have dispersed after the flood of the Sete Quedas Falls. The presence of juveniles along with adults indicates that the species is undergoing an establishment stage of the invasion process in the region. Keywords: Tibagi River, biological invasion, fishes, diversity loss.

Highlights

Erythrinus erythrinus é um erythrinídeo nativo das bacias do Amazonas, Orinoco, rios costeiros da Guiana e Baixo Paraná, mas alóctone da região do rio Tibagi, bacia do Paranapanema
The biological invasion by fishes is a process associated with dam constructions, water transpositions, trade and international traffic, promoting changes in biological diversity, a common event in countries with more intense trade activities (Xu et al, 2012)
Among the causes of translocations of allochthonous fish in northern Paraná State is the flooding of the Sete Quedas Falls, geographical barrier after the construction of the Itaipu Dam on the Paraná River (Júlio Jr. et al, 2009); escapes from fish farms (Orsi and Agostinho, 1999); releases for sport fishing (Orsi and Britton, 2012), and releases of aquarium fish (Garcia et al, 2014a)

Summary

Introduction

Erythrinus erythrinus é um erythrinídeo nativo das bacias do Amazonas, Orinoco, rios costeiros da Guiana e Baixo Paraná, mas alóctone da região do rio Tibagi, bacia do Paranapanema. The release of remaining live baits at the end of the amateur and sport fishing seasons (Orsi and Britton, 2014) contributed to the translocations of species in the environment. Given the processes of biological invasion in freshwater ecosystems, the present work aimed at verifying the occurrence of constancy and the condition of health of its specimens in sub-tributaries of the Lower Paranapanema River, to test the hypothesis that this species is undergoing an establishment stage of the introduction process in that basin.

Results

Conclusion