Spawning Stock–Recruitment Relationships of White Shrimp in the Southwestern Gulf of Mexico

Abstract

The annual spawner-recruit relationship for white shrimp Penaeus setiferus in the southwestern Gulf of Mexico did not show a significant correlation (0.10 > P > 0.05) from 1973 to 1984.1 attribute this to the effect of environmental factors as well as to the interannual variability of recruitment strength in the main cohorts throughout each year. A Ricker stock-recruitment relationship was established for dominant cohorts in the 1973–1984 study period. The variance explained by the model increased from 70 to 82% (multiple correlation r = 0.903, P < 0.001) when river discharges during the spawning month and before recruitment were included. I propose that the magnitude of recruitment largely depends on the carrying capacity of critical nursery habitats. Fishing effort is related to recruit abundance and has a direct effect in determining spawner stock size (multiple correlation r = 0.91, P < 0.001). Through multiple-regression techniques, a surface was defined where the recruitment level varied according to spawning stock size as well as to river discharge.