262 



Fishery Bulletin 9 1(2), 1993 



sons, with the main difference being the shift in the 

 winter curve to the right (Fig. 1A). Because of season- 

 ally-induced differences in somatic growth (Jackson & 

 Choat 1992), males matured later in winter. The rela- 

 tionship between age and testis weight had greater 

 variability in winter, which suggests that age-at- 

 maturity was less well-defined in the winter, with a 

 slower rate of maturity in some individuals. 



In both winter and summer, males with a testis 

 weight >0.1g had spermatophores present. However, 

 there was variability in age-at-maturity in both sea- 

 sons, with testis weight in apparent immature males 

 of 0.307-0.335 g. The youngest mature male during 



summer and winter was 83d and Hid, respectively. 

 The oldest immature males for summer and winter 

 were 90 d and 130 d, respectively. 



There were also seasonal differences in maturity pat- 

 terns of females based on ovary weight (Fig. IB). Fe- 

 males matured in summer at a young age, with the 

 ovary reaching a large size in 65-85 d, although two 

 older specimens were immature. This was especially 

 apparent in the oldest individual (lOOd) which also 

 had very undeveloped nidamental glands. 



All females in the winter sample had small gonads 

 and nidamental glands, and there were no mature or 

 soon-to-be-mature females. This differed from the pat- 



