Spatial and temporal variations of the abundance of eggs and larvae of Micropogonias furnieri in the Patos Lagoon estuary: historical records and environmental forces

Abstract

Fish species from the Patos Lagoon Estuary (PLE) adopt different spawning strategies to optimize the balance between remote and local environmental conditions during their life cycle. The purpose of this study was to describe and analyze the spatial distribution, temporal variability and the influence of environmental variables on the abundance of eggs and larvae of Micropogonias furnieri in the PLE. Environmental variables and ichthyoplankton historical records were used in the analysis. Ichthyoplankton was collected with a 300 or 500 μm-plankton net in monthly and/or fortnightly samples. Analysis of variance was used to test the effects of spatial distribution and temporal variation on the average abundance of eggs and larvae. Temperature, salinity, atmospheric pressure and winds were important for the seasonal variability of abundance, while precipitation and water discharge were important for interannual differences. The abundance of eggs and larvae in the estuary was higher in the lower estuary during spring and summer. These results suggest that the variability in the distribution of early life stages of M. furnieri is determined at different time scales.