Composição e abundância do Ictoplâncton em um lago de inundação, Baixo Amazonas, Pará.

Abstract

The present work aims to characterize the biological and ecological attributes of the ichthyoplankton related to the temporal distribution in Lake Maicá, Santarém, as a way to assist in the definition of best practices for the sustainable use of biodiversity that have been increasingly important in the current scenario. The ichthyoplankton collections were carried out from January to December 2015 in nine stations, in day and night sampling cycles by means of horizontal trawls in the subsurface of the water column using conical plankton net (300μm). The order of Characiformes (41.79%) and Clupeiformes (31.48%) were the most abundant, accounting for 73.27% of the total captured larvae. The ichthioplankton community was composed mainly of small and medium-sized species, sedentary or that carry out short and medium migrations. The distribution of organisms differed significantly between the months, with the highest average egg densities (13.38 org.10m- ³) and larvae (13.78 org.10m- ³) in January and December respectively, corresponding to the reproduction of the majority of species exploited by fishing in the region. Among the species identified, most are of commercial importance and are widely exploited by fishing and consumed by the local population. The ordering analysis of the NMDS showed a seasonal gradient in the distribution of fish larvae in the months. PERMANOVA found a significant difference (Pseudo F = 0.94, gl = 50 p