Growth parameters and mortality of Eucinostomus argenteus(Baird & Girard, 1854) captured in Guaratiba mangrove, Sepetiba Bay, RJ

Abstract

The analysis and understanding of fish growth are important for the knowledge of their population dynamics. In this context, growth parameters were calculated for Eucinostomus argenteus (carapicu), one of the most abundant species in Sepetiba Bay (RJ), Brazil. Growth parameters were estimated based on length frequency distribution data according to ELEFAN I and Bhattacharya methods, using the FISAT software. The estimated growth parameters were: asymptotic length L∞ = 28.31 cm; growth rate coefficient k = 0.61 year^-1; natural mortality coefficient M = 1.53 year^-1. Longevity estimates, defined as the time (years) for a fish to reach 95% of the asymptotic length, was 4.34 years. Three cohorts were indicated by the Bhattacharya method in more than half of the monthly samples, corroborating the results of ELEFAN I method, which is based on modal displacement of temporal sequences of length samples. This last method evidenced the presence of 5 cohorts according to the best fit of Rn ("goodness of fit indexâ€Â), 2 of this cohorts clearly corresponding to the observed data in the study area. Therefore, the growth parameters and mortality estimated to Sepetiba Bay E. argenteus populations contribute to knowledge of the species biology and represent progress toward an appropriate and necessary management for biodiversity conservation.