Fishery evaluation: Lutjanus peru (Pisces : Lutjanidae) from Guerrero, Mexico

Red snapper (Lutjanus peru) fishery was analyzed from landings and catch re cords. Stock age structure was reconstructed after the parameter values of the von Bertalanffy growth model, the length-weight relationship, ages and the natural mortality coefficient through each of nine years of catch recor ds. The Fisat software package was applied to assess population parameters, whose estimates are, for the von Bertalanffy growth model, K = 0.1442 to 0 .38; to = -0.2; L = 87 cm; W = 9.4 Kg, and the natural mortality coefficien t (M) after several methods (0.14 to 0.38). Cohort size was assessed by the virtual population analysis (VPA), estimating population size in 5.2*10(6) fish with a biomass of 8 454 tonnes. Current fishing mortality F, ranges f rom 0.06 to 1.13, depending upon the chosen M value; according to this, whe n the M value used is low, the results suggest that the stock is underexplo ited, and vice versa. The yield per recruit model applied suggests improvem ents to the management strategy. The model indicates recruit overfishing be cause very small fish are the main target (tc less than or equal to 1), nea rly 50 % of fish caught are immature and under one year of age. Optimum yie ld levels correspond to first catch age of 2 to 3 years and a fishing morta lity of F = 0.35, suggesting the need of limiting small fish catch of to a minimum of 2 year old specimens.