Roumillat and Brouwer: Reproductive dynamics of Cynoscion nebulosus 



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80 30W 80 O'W 79 30'W 



Figure 1 



The three South Carolina estuarine systems (indicated by arrows) where C. nebulosus were collected. 



Table 1 



Criteria used for microscopic staging of C. nebulosus ovaries. FOM = final oocyte maturation; POF = postovulatory follicle. 



Stage 



Description 



Immature Ovary small in cross section. Early stage with only oogonia evident; later stage with small 



(<0.08 mm) primary oocytes, tightly packed. No evidence of early vitellogenesis. 



Developing First appearance of cortical alveoli stage oocytes through late vitellogenesis but no evidence of early 



FOM (lipid and yolk globule coalescence). 



Ripe Ovary containing oocytes demonstrating FOM (lipid and yolk coalescence through hydration). 



Mature with day-0 POFs Ovary exhibits POFs <24 h (see Table 2 ). Found at all water temperatures throughout the spawning 



season. 

 Mature with day-1 POFs Ovary exhibits POFs >24 h consisting of closely packed granulosa cells (0.08-0.1 mml. Only 



identified in water < 25°C. 



Spent Ovary containing alpha- and beta-stage oocytic atresia. 



Resting Ovary containing small primary oocytes and oocytes with perinuclear nucleoli (<0.12 mm); 



usually some remnants of oocytic atresia. 



of diamond wafering blades. The resulting section was was assumed for the process of aging. Spotted seatrout 



mounted on a labeled microscope slide and examined deposit an annulus in April or May (Murphy and Taylor, 



with a Nikon SMZ-U microscope. A 1 January birth date 1994; Wenner et al. 4 ). Fish in the first three months of 



