Reproductive Characteristics of Dusky Grouper (Epinephelus guaza, Linnaeus, 1758) in Antalya Bay of Eastern Mediterranean

This study aimed to investigate sexual cycles and reproductive characteristics of dusky grouper (Epinephelus guaza L. 1758) in Antalya Bay of Eastern Mediterranean, Turkey. A total of 104 dusky groupers were collected during a year by spear-fishing. Their 13 developmental stages of reproduction were determined. The first step was named as juvenile; the gonads were ovo-testes. The female characters started to begin after the juvenile form. All the fishes had different six female stages (F1 to F6) according to gonad ripening. The first sexual maturity of the females was observed in F3 stage with 1-3 years old and 39.1cm (LS). Three transitional periods (T1, T2, T3,) were seen beyond of the female period (4-6 years old). Intersexual periods were followed by testicular phases. The fishes underwent to male sex which included three stages (M1, M2, M3). The first sexual maturity of the males (M2; 7-8 years old) was started at 83.5cm (LS). According to data, gonado-somatic index (GSI) peaked in between July and September in females while it was peaked in between May and July in males. Furthermore, mating time started in May as assessed on the basis of GSI and IRG which were parallel in males and females.