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Fishery Bulletin 102(3) 



months and ages revealed that age had no effect 

 on oocyte diameter (ANOVA, P=0.82). However, 

 the effect of month corroborated the pattern of 

 increasing RF as the spawning season progressed: 

 oocytes were significantly smaller at the end of 

 the season (ANOVA, P<0.05). 



Annual fecundity 



Annual fecundity estimates (summation of MEP) 

 were approximately 3.2 million. 9.5 million, and 

 17.6 million oocytes for each age class, respec- 

 tively (Table 4). The equation below describes the 

 relationship between AF and age: 



AF = 7152762(Age) - 4166620 (r 2 =0.99> P<0.05. 



From this relationship, the predicted AF for 

 ages 4 and 5 were 24,444,430 and 31,597,190 oo- 

 cytes, respectively. We expanded AF in relation to 

 the abundance of each age class in our standard 

 random samples for the three years of the study. 

 We estimated that the overall average contribu- 

 tion from age-1 fish to the reproductive output 

 for the season was approximately 29% . whereas 

 fish aged 2 and 3 contributed 39% and 21', of 

 oocytes, respectively. Ages 4-5 comprised less 

 than 3% of specimens sampled and contributed 

 7% and 4% based on predicted AF values. 



Discussion 



Studies on the reproductive biology of Cynoscion 

 nebulosus have established group-synchrony and 

 indeterminate fecundity for this species through- 

 out its range (i.e. Brown-Peterson et al., 1988; 

 Brown-Peterson and Warren, 2001; Nieland et 

 al., 2002; Mercer 1 and references therein). Fish 

 with these features release gametes in several 

 batches over a protracted spawning season and 

 annual fecundity is not fixed prior to the onset of 

 spawning (Wallace and Selman. 1981). 



Based on mtDNA variation among spotted sea- 

 trout, the existence of two populations, one in 

 the Gulf of Mexico and one in the South Atlantic, 

 was established by Gold et al. (1999). However, 

 variations in reproductive parameters have been 

 suggested among geographic locations within the 

 Gulf of Mexico (Brown-Peterson et al., 2002). 

 Wiley (1996) suggested that spotted seatrout com- 

 prise a single stock in South Carolina: therefore 

 reproductive parameters presented in the present 

 study should be applicable only to the spotted 

 seatrout population inhabiting coastal waters of 

 this state. Further studies should be conducted 

 to evaluate the applicability of these parameters 

 to the entire southeast coast. 



Other investigators (Brown-Peterson et al., 

 1988; Wieting, 1989; Brown-Peterson and War- 



