Distribuição espaço-temporal da ictiofauna de poças de maré de um estuário amazônico: interação de fatores

Abstract

The intertidal rockpool ichthyofauna has been studied for several years in temperate and tropical regions at the Pacific Coast, however, in Brazil, the knowledge about it is still incipient. The aim of the present study was to investigate the fish assemblages in tidepools located in three different habitats: rocky outcrop, mangrove forest and salt marsh, at Areuá Island, Curuçá river estuary, North Brazil. Samples were taken quarterly from February 2009 to November 2009, during the spring tide, following a standardized methodology. The physicochemical parameters changed along a topographic gradient and were responsible for the spatio-temporal distribution of fish fauna at rocky outcrop tidepools. Salinty, mean depth and substrate heterogeneity were the parameters that more explained the variations in fish fauna distribution A clear segregation of fish assemblages was found between the tidepools of rocky outcrop and vegetated habitats (tideools in mangrove forest and saltmarsh). These findings suggest that the fish fauna has preferences for some habitats influenced by environmental variables and substrate heterogeneity. However, more researches should be conducted taking into account inter-and intra-specific relationships.