PARRISH ET AL.: AGE DEPENDENT FECUNDITY IN NORTHERN ANCHOVY 



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Figure 4.— The monthly percentages of grouped maturity stages 

 for female northern anchovies, by size group. A. Stages 1 + 2 B. 

 Stage 3. C. Stages 4-7. 



stages 1 + 2 occurs in February to April. The per- 

 centage of females just beginning to mature (i.e., 

 stage 3) has an abrupt peak in February-March in 

 the smallest size class (Fig. 4B). This peak becomes 

 increasingly spread out in the larger size classes. 

 The higher maturity stages (4-7) are most abundant 

 from February to April in all size classes (Fig. 4C). 

 The larger size classes have much larger percent- 

 ages of females in the higher maturity stages than 

 the smaller size classes, and there is a minor peak 

 in the percentage of the higher maturity stages dur- 

 ing the fall in the two largest size classes. Analysis 

 of the data by age group showed, as would be ex- 



pected, that increased age has essentially the same 

 effect as increased size on the magnitude and dura- 

 tion of maturation stages. 



SPAWNING INCIDENCE AND 

 FECUNDITY 



Studies by Hunter and Goldberg (1980) in Califor- 

 nia and Alheit et al. (1983) in Peru examined post- 

 ovulatory follicles to determine the spawning 

 frequency of female anchovies (i.e., the time inter- 

 val between spawnings). A second method would be 

 to determine the percentage of females with 



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