Influence of the flooding regime on the nutritional state and juvenile recruitment of the curimba, Prochilodus scrofa, Steindachner, in upper Paraná River, Brazil

Abstract

The relationship between the flooding pattern of the Paraná river floodplain and the nutritional state and juvenile growth of the curimba, Prochilodus scrofa Steindachner, over three years and its recruitment to the Itaipu reservoir fish stocks over six years were analysed. Seasonal and annual variation in the condition factor and visceral-somatic relationship were positively influenced by high water levels. A similar effect was found for growth during the second year of life. Recruitment success was found to be related to the occurrence of floods in summer and autumn. The importance of the annual floods to the availability of food, refuges and survival of P. scrofa are discussed in relation to the operation of the upstream dams.