Passage performance of long-distance upstream migrants at a large dam on the Paraná River and the compounding effects of entry and ascent

Abstract

This paper presents results of a fishway evaluation performed at the Engenheiro Sérgio Motta Hydroelectric Power Plant (known as Porto Primavera) -CESP, Paraná River, Brazil. The evaluation was designed to quantify entry and passage proportions of 4 long-distance migratory fish species: Brycon orbignyanus (piracanjuba), Piaractus mesopotamicus (pacu), Prochilodus lineatus (curimba), and Rhinelepis aspera (cascudo-preto). Proportions finding and entering the fishway differed between species, ranged from 7.4 % (Prochilodus lineatus) to 55.4% (Piaractus mesopotamicus). Also, proportion passing was different between species, ranged from 31% (R. aspera) to 100% (Prochilodus lineatus). Fish that were marked and released within the fishway had greater failure rates than those that entered volitionally. Total time to pass ranged from 1.48 hours (Prochilodus lineatus) to 178.9 hours (R. aspera). Failure rates were greatest in the lower end of the fishway. Although some individuals of all species passed successfully, significant challenges remain to restoring connectivity of the upper Paraná River.Este artigo apresenta resultados da avaliação de passagem de peixes na escada localizada na Usina Hidrelétrica Engenheiro Sérgio Motta -CESP (rio Paraná, Porto Primavera, Brasil). A avaliação foi concebida para quantificar a entrada e proporções de passagem de quatro espécies de peixes migradores de longa distância: Brycon orbignyanus (piracanjuba), Piaractus mesopotamicus (pacu), Prochilodus lineatus (curimba) e Rhinelepis aspera (cascudo-preto). As proporções de encontrar e entrar na escada variaram de 7,4% (Prochilodus lineatus) para 55,4% (Piaractus mesopotamicus). A proporção de passagem através da escada variou de 31% (R. aspera) a 100% (Prochilodus lineatus). Os peixes que foram marcados e soltos no interior da escada apresentaram taxas maiores de falha do que aqueles que entraram voluntariamente. O tempo médio para passar variou de 1,48 horas (Prochilodus lineatus) para 178,9 horas (R. aspera). A taxa de falha foi maior no extremo inferior da passagem para peixes. Embora alguns indivíduos de todas as espécies passaram com sucesso, desafios significantes permanecem para restaurar a conectividade do alto rio Paraná.

Genetic structure and diversity of migratory freshwater fish in a fragmented Neotropical river system

“…In addition, connectivity might have been maintained by fish passages constructed at the dams as already reported elsewhere (Makrakis et al 2007(Makrakis et al , 2011Wagner et al 2012). Thus, the results obtained could have influences from the high migration capacity of P. lineatus and the connectivity maintained by fish passages.…”

“…Similarly, Makrakis et al (2012) reported significant lateral movements towards tributaries and upstream and downstream movements along the Parana River. Mark and recapture studies Wagner et al 2012;Fontes Jr. et al 2012) have also shown that P. lineatus can move upstream in the Piracema Channel to the Itaipu Reservoir, and that some of these specimens also scaled the Porto Primavera Reservoir fish ladder (Wagner et al 2012) when migrating to reservoir tributaries . Makrakis et al (2012) stressed the need to conserve the few remaining unaltered tributaries in the Paraná River basin, since fragmentation of these environments could result in additional pressures on migratory fish populations.…”

“…In the Upper Paraná River, fish passages were installed in the Itaipu Dam, the Piracema Channel (a fish passage system 10 km long), and in the Porto Primavera Dam. Studies were conducted to evaluate the Porto Primavera fish ladder in terms of the abundance of migratory fish species (Makrakis et al 2007) and to quantify entry and passage proportions (Wagner et al 2012). Studies in the Piracema Channel we also conducted to evaluate the ascension rate (Makrakis et al 2011).…”

“…Studies in the Piracema Channel we also conducted to evaluate the ascension rate (Makrakis et al 2011). For the Porto Primavera fish ladder, Wagner et al (2012) reported low proportions of fish entering the fishway and generally low proportions passing through it, except for Prochilodus lineatus. At the same location, Makrakis et al (2007) found eleven migratory fish species; however, the fishway appears to selectively favor species with strong swimming capabilities and the number of migratory fish decreased downstream to upstream of the fish ladder, showing a similar pattern to that found in the Piracema Channel (Makrakis et al 2011).…”

Ascent ability of brown trout,Salmo trutta, and two Iberian cyprinids − Iberian barbel,Luciobarbus bocagei, and northern straight-mouth nase,Pseudochondrostoma duriense− in a vertical slot fishway

“…It is likely that the reduced motivation and increased transit time exhibited by the trout was related in part to the lower temperatures experienced by that species. Motivation is one of the key factors driving passage performance, although it is rarely measured (Castro-Santos, 2004;Wagner et al, 2012;Cooke and Hinch, 2013). Tagging and handling may also influence motivation.…”