Abstract

Identification and analysis of growth rings in tropical fishes is somewhat difficult because of overlapping of age classes due to all year around spawning and recruitment. In this work the growth of huachinango Lutjanus campechanus of the Gulf of Mexico is estimated on the basis of size frequencies (indirect method) and the interpretation of growth rings (direct method). The variability of parameters was quantified applying bootstrap and jackknife techniques. The former was applied to observed and backcalculated lengths by age determined form growth rings, and the second was used jointly with ELEFAN, SLCA and PROJMAT techniques. The 95% of bootstrap distribution of the parameters was within L 4 =78-133 cm and K=0.06-0.28/year for backcalculated lengths and L 4 =86-173 cm, K=0.05-0.24/year for observed ones. The application of indirect methods with jackknife showed different results: ELEFAN and PROJMAT overestimated L /while SLCA coincided with the values reported in the existing literature for direct methods Values for the comparative growth index `agreed with the observed ones for different geographic regions (between 2.92 and 3.19), except for ELEFAN and PROJMAT.

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