AGE AND GROWTH OF THE BRAZILIAN CODLING (Urophycis brasiliensis) CAUGHT IN THE SOUTH OF BRAZIL

Abstract

The Brazilian codling (Urophycis brasilienis) is one of the most important species usually caught by trawlers offshore of south and southwest Brazilian coast. Estimates gathered during the REVIZEE project indicated that this fishery resource is probably overexploited. Nevertheless, there is some doubt on the validity of this diagnosis due to uncertain on age determinations used for the stock assessment analysis. The scope of this work was to lessen this uncertainty. We analyzed 390 otoliths extracted from saleable fish landed in Itajaí-SC during 1997 and 1998, and 60 otoliths extracted from fish smaller than the saleable size, landed in 2003. The results obtained by two validation methods support the hypothesis that one growth increment (i.e. couple of a translucid plus a opaque band) is layered each year. The youngest and the oldest fishes found were 3 and 16 years old respectively. We estimated parameters of the von Bertalanffy growth model for female data set and for both sexes pooled. The small sample size makes the growth estimation impractical for males. The female growth curve was Lt=75,67(1-e-0,106(t+3,05)), while the curve estimated for pooled data set was Lt=62,25(1-e-0,106(t+0,53)). These are the most accurate parameters for the Brazilian codling available and should be used in the future stock assessment analysis.