Reproductive strategy of Hypomasticus copelandii: the piau-vermelho can adapt to small lotic stretches and lentic environments, or depends on the migration to complete its life cycle?

Abstract

Introduction: The fish reproduction knowledge is essential to support fish management, conservation and exploitation of the fish stocks. Fish species migrate for various purposes during different periods of their life cycle, and this involves spawning migration, habitat shifts of juveniles and drift of larval fish. Objective: Our main objective was to investigate whether the H. copelandii can adapt to small lotic stretches and lentic environments or depends on the migration to complete its life cycle. Methodology: Samplings were carried out on two tributaries of the Doce River, both containing small hydroelectric power stations in their courses, in Corrente Grande River (CGR) and in the Manhuaçu River (MR). In the CGR 408 specimens (64 females, 109 males and 235 juvenile) were captured, while in the MR were captured 64 females, 76 males and 45 juveniles. Results: Our results shows that the blockage of rivers caused by the construction of the power plants and their operation did not result in a direct negative effect on H. copelandii populations. For both rivers, our study demonstrates the maintenance of reproductive activity and the recruitment process, inserting new individuals into the environment. Conclusion: So, we showed that H. copelandii can adapt their reproductive strategy, getting reproductive success in very small lotic stretches or a semi lentic water body, indicating that the reproductive strategies of H. copelandii is not only a genetic phenomenon but can undergo ecological adaptations. Thus, the reproductive strategies of H. copelandii could undergo temporal and spatial changes and could be conditioned by environmental pressure. Keywords: Neotropical fish; Reproductive migration; Doce River basin; Environmental changes.