Baelde Biology and dynamics of reproduction in Hyperoglyphe antarctica 



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v-ir* 





D 

 < 









C 'V* 



^•J^f py - 

 z ^ 



^5ft 



rJ 



Figure 2 



Histological sections showing ovary maturation stages of blue-eye trevalla, Hyperoglyphe antarctica. (A-F) repre- 

 sent stages 1-6 successively. (D) shows an "early stage 4" characterized by the nonuniform size of yolked oocytes, h 

 = hydrating oocyte (irregular shape due to loss of fluid during histological processing); n = nucleus; o = oil droplet; 

 py = partially yolked oocyte; u = unyolked oocyte; y = yolked oocyte; ym = yolk mass (fusion of yolk plates); yp = yolk 

 plate; z = zona radiata. 



eter, see below) were used to estimate the annual 

 fecundity of blue-eye trevalla. Before estimating fe- 

 cundity, a check was made that the oocytes were 

 uniformly distributed within the ovaries. From five 

 fish, the number of oocytes per gram was compared 

 between subsamples taken across the ovaries (near 

 the periphery and near the center) and along the 

 ovaries (within the anterior, median, and posterior- 



regions). ANOVA showed no differences between 

 subsamples across the ovaries (F=0.68, df=l,4, 

 P=0.42), or between subsamples along the ovaries 

 (F=0.74, df=2,8,P=0.49). Oocytes were then routinely 

 dissociated and counted from three weighed 

 subsamples taken randomly within the ovaries. 



Batch fecundity was estimated for eight ripe fe- 

 males by estimating the number of hydrated oocytes; 



