Red Grouper Reproduction in the Southern Gulf of Mexico

Abstract

Abstract The reproductive biology of red grouper Epinephelus morio from the inshore and offshore waters of the Yucatan Peninsula (Campeche Bank) was investigated over a 5-year period (1988–1993). Results confirmed that red grouper is a monandric protogynous hermaphrodite as shown by (1) the absence of primary males in samples, (2) the presence of transitionals in the population (1% of the total offshore catches), (3) the occurrence of a membrane-lined central cavity in the testes of all males and dorsal sinuses in the gonadal wall in most males, (4) the significant difference in size ranges and mean fork lengths of males and females, and (5) a female-biased male : female ratio in size-classes less than 72.0 cm fork length (FL). We found immature females all year round in inshore waters and immature females, mature females, and males, and transitionals in offshore waters. In the southern Gulf of Mexico, the species displayed seasonal reproduction, with single, annual peak spawning occurring in late winter ...