Population dynamics of the striped, mojarra Eugerres plumieri from the Cienaga Grande de Santa Marta, Colombia

The striped mojarra Eugerres plumieri is one of the most important fishing resources in the Cienaga Grande de Santa Marta, the main coastal lagoon in the Colombian Caribbean. Fishing surveys and commercial catch during 1993 a nd 1994 provided information to estimate the basic population characteristi cs: biomass, reproduction, growth, mortality, recruitment and yield per rec ruit. The estimated biomass was 286 t in November 1993, 171 t in March 1994 , 112 t in June 1994 and 112 t in August 1994, being largest in the rainy s eason (September-November). Its distribution is determined by the displacem ent of the population during the dry and rainy seasons to areas near the ri vers and the sea. The reproductive cycle was annual with mature individuals present during the whole year and a maturity peak in the dry season. The g rowth parameters were estimated by three methods ELEFAN I, SLCA and PROJMAT , quantifying its variability by means of the jackknife technique. The best estimates were obtained by SLCA and ELEFAN I (L-infinity=41.2 cm, K=0.32 y ear(-1) and L-infinity=41.9 cm, K=0.30 year(-1), respectively). Estimates o f the growth index phi' ranged from 2.5 to 2.8, and were consistent with th ose reported in the literature. According to the variation of the exploitat ion rate, Eugerres plumieri may be overexploited in terms of yield and biom ass per recruit. It is recommended that the fishing effort and the mean len gth at capture be reduced. (C) 1999 Elsevier Science B.V. All rights reserv ed.