Abstract

The pressure by excessive fishing can cause an alteration in the reproductive Biology of fish and, particularly in the hermaphroditic species which form reproductive aggregations, as it is in the case of groupers. In the Southeast of the Gulf of Mexico (Bank of Campeche) the species of grouper -of great commercial importance-, The red grouper Epinephelus morio V. 1828, is over exploited at the moment. The present work aimed to analyze if changes in some reproductive parameters of red grouper of the Bank of Campeche in the period 1989-2004 took place. Three seasons of study (1989-1992; 1996-1998 and 2003-2004), which included the months of reproductive period of the species were compared. The considered reproductive parameters were: the frequency allocations of sizes and the medium sizes of males and females as well as the proportion by gender. Temporary values of the first two parameters were compared by means of nonparametric tests of Kolmogorov- Smirnov and Kruskal- Wallis. The test of G replicated was used to determine if the proportions of male and female (M:H) obtained by season of study were significantly different from a balanced relation of gender (1:1). The main obtained results allowed to observe, independently of sex, a significant diminution of the sizes of the individuals during the period of stud. Notwithstanding, the males always presented sizes significantly superior to those of the females not matter the season, and to the proportion by sex always remained balanced in favor of the females as it is hoped to observe generally in the case of a species protogine hermaphroditic

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