FISH BIODIVERSITY IN INTERMITTENT STREAMS OF THE BRAZILIAN SEMIARID REGION (ACARAÚ RIVERBASIN, BRAZIL)

Abstract

Intermittent rivers and streams are dynamic environments that experience partial or total flow drying during the dry season and are the dominant aquatic ecosystems in Northeast Brazil. Flowing, pools e drought cycle directly influences the dynamic of aquatic community in these systems. Thus, this study aimed to characterize the composition and structure of fish assemblage in aquatic phases of the hydrological cycle of intermittent streams in the Brazilian semiarid region. This study was conducted in five streams in the Acaraú River basin, Ceará, Northeastern, Brazil, in flowing and pool phases. Dominant fish species differed between aquatic phases of the cycle. However, none of the ecological descriptors showed a significant difference between phases, and none of the 25 species was considered an indicator of phases. Species present in these streams are adapted to the natural dynamics of intermittent systems and refuge in the pools during the dry period, therefore, it is fundamental to consider the changes along the hydrological cycle in actions that aim to protect intermittent rivers and streams