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Fishery Bulletin 94(4). 1996 



compared. The locations were anterior, center, and 

 posterior in both the left and right lobes of the ovary. 

 A wedge from the exterior of the ovary to the inte- 

 rior of the ovary was taken for each location sampled. 

 A two-way ANOVA was run to test for effects of loca- 

 tion and individual fish on oocyte density. 



Whole oocytes were staged by using the criteria of 

 Hunter et al. (1992). Yolk density was used to dis- 



criminate between the different developmental 

 stages of oocytes, with counts of stage-3 AYO's (Fig. 

 2A) being the basis of TF estimates. The definitions 

 of each stage were as follows: 



Stage 1 Initial layer of yolk along the periphery 

 of the oocyte appearing as a narrow band 

 but not extending over 20% of the distance 



Table 1 



Histological stages of female vermilion snapper, Rhomboplites aurorubens, modified from Hunter et al. ( 1992). 



Inactive 



Active 



Not capable of spawning now or in the near future. 



Mature 



Ovaries show clear evidence of past spawning or past 

 maturation of AYO's. 



Postspawning. Contains either postovulatory follicles 

 (POF's) and no AYO's, or contains POF's with mostly atretic 

 AYO's. 



Major atresia. AYO's present, alpha atresia of AYO's >50% . 



Uncertain maturity 

 No AYO's present. 



Early yolked. Early yolked oocytes present. May have alpha, 

 beta, or no atresia of early yolked oocytes. 



Unyolked. Unyolked oocytes present. Alpha or beta atresia 

 of unyolked oocytes evident. 



Immature 



Unyolked oocytes present with no atresia. 



Capable of spawning now or in the near future. Ovary 

 contained enough advanced yolked-oocytes (AYO's) for 

 one spawning. 



Mature 



AYO's present with no or minor (<49%) alpha atresia of 

 AYO's. 



Spawning. Evidence of past spawning (POF's) or imminent 

 spawning (hydrated oocytes [HO's]) or migratory nucleus- 

 stage oocytes (MNO's). 



Nonspawning. No evidence of recent or imminent spawning, 

 but fish are capable of spawning in the near future. 



Table 2 



Histological staging of male vermilion snapper following modified criteria developed by Wyanski and Pashuk ( 1990). 



Inactive 



Active 



Not capable of spawning now or in the near future. 



Mature 



Spent. No spermatogenesis; some residual sperm in tubules 

 and lumina. 



Resting. Large cross section compared to immature male; 

 little or no spermatocyte development; empty tubules and 

 lumina evident. 



Immature 



Small cross section compared to resting male; little or no 

 spermatocyte development; empty tubules and lumina not 

 evident. 



Capable c if spawning now nr in the near future 



Mature 



Developing. A few primary and secondary spermatocytes 

 through tubules and lumina (no spaces) with spermatozoa. 



Ripe. Predominance of spermatozoa; areas of 

 spermatogenesis toward outer surface of testes in some 

 specimens. 



