The actual morphology of the gonad, however, 

 differs from that described for red grouper. Moe 

 (1969) cited Smith's (1965) description of an E. 

 fulvus ovary, but Smith did not mention the 

 "typhlosole-type" structure from which ovarian 

 lamellae are suspended that was found in gag 

 gonads in the present study. This structure is also 

 found in M. phenax, M. inter stitialis , E. adscen- 

 cionis. E. drummondhayi , E. flavolimhatus , and 

 E. niveatus (Roumillat, unpubl. data) and may be 

 present in other gi'oupers. 



Although Moe (1969) found only 1.43Vr of red 

 groupers undergoing sexual succession, the per- 

 centage offish with transitional gonads was even 

 lower in the gag (1.257^). These frequencies are 

 much lower than the transitional frequencies of 

 such sympatric species as Centropristis striata 

 (14'7f; Wenner et al. 1986), Calamus leucosteus 

 (10-139r; Waltz et al. 1982), Pagrus pagrus (10%; 

 Roumillat, unpubl. data), and Hemanthias vi- 

 vanus (9%; Hastings 1981). A rapid rate of sex 

 succession is probably the reason for the low fre- 

 quency of transitional gonads found. Smith ( 1965) 

 and Moe (1969) suggested that other gi-oupers 

 have a very quick rate of succession, and Fishel- 

 son (1970) and Shapiro (1981) have shown that 

 Anthias squamipinnis can change sex within a 

 few weeks. 



Despite suggestions that gag transform to 

 males during their 10th or 11th year (McErlean 

 and Smith 1964), it is evident that sexual succes- 

 sion occurs at younger ages. Only seven transi- 

 tional gag were collected, and of the five that were 

 aged, there was one each in age gr-oups V, VI, VII, 

 VIII, and XI. However, age X was the group in 

 which the sex ratio approximated unity. The age 

 of first maturity for females was lower than the 

 previously speculated fifth or sixth year (McEr- 

 lean and Smith 1964), and 289^ of age III, 517r of 

 age IV, and all older femal gag had mature go- 

 nads. Thus, there may be significantly more gag 

 (all females because of protogyny) producing 

 gametes than indicated in the literature, suggest- 

 ing a greater ability to rebound from intensive 

 overfishing than previously suspected. 



Acknowledgments 



Appreciation is expressed to C. Wenner (South 

 Carolina Marine Resources Research Institute) 

 for his considerable contribution to this work, and 

 to C. Manooch (National Marine Fisheries Serv- 

 ice, Beaufort, NC) for his helpful review of the 

 manuscript. The study was sponsored by the Na- 



tional Marine Fisheries Service (Southeast Fish- 

 eries Center) under Contract 6-35147, and by the 

 South Carolina Wildlife and Marine Resources 

 Department. 



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