Edad y crecimiento del mero Acanthistius brasilianus (Pisces, Serranidae) en el Golfo San Matías (Rio Negro, Argentina).

RUBINICH, J.; GONZÁLEZ, R.

San Andrés Isla, Colombia

Congreso; IX Congreso Latinoamericano de Ciencias del Mar; 2001

The objective of this work was to select an appropriate growth model and to estimate the growth parameters for the patagonian grouper A. brasilianus. Samples were obtained between 1990 and 1993 from San Matías gulf’s trawl fishery. Saggita otholits from 750 groupers were examined. Length-weight relationships for both sexes were fitted and allometric coefficients (b) were estimated. Regarding this information a growth model was fitted for each sex. Two versions of the von Bertalanffy model were used: special  (for isometric growth) and generalized (for allometric growth). Functions were fitted using generalized minimum squares and growth parameters were estimated with maximum likelihood. Length-weight relationships for both sexes were not different (P>0,157). A pooled allometric coefficient (b = 2.7) indicated a small negative allometry in the relation length - body weight. Differences in growth models (both special and generalized) for each sex, were not significant (P>0,1). As regards the simplicity and broad spread, we conclude that the special von Bertalanffy growth model obtained in this study ( Lt = 50,74 * [1- e – 0,07 * (t –(-4,5)] ) is the most appropriate to describe the growth of both sexes of the patagonian grouper A. brasilianus.