Stanley and Kronlund: Life history characteristics for Sebastes brevispmis 



675 



peak period of mating is presumably December to Febru- 

 ary. One sample of 109 males, collected in March 1988, 

 was recorded entirely as maturing. This one sample 

 accounted for all but two records of stage-4 males col- 

 lected in March and, therefore, contradicted the results 

 of 20 other March samples, totalling 364 specimens. 

 Although we found no evidence of a recording error, we 

 suggest that these specimens were misclassified and were 

 probably recovering instead of developing males. 



The developing ovaries (stages 2 and 3), observed 

 from January to April, shifted to fertilized through to 

 resting stages (stages 3-7) in April to June. Eyed lar- 

 vae were commonly observed from May to July although 

 a few individuals with eyed larvae were observed in 

 February, August, and October. 



We examined whether there was a relationship be- 

 tween the size of the female and the timing of par- 

 turition by categorizing July observations as either 



"parturition not completed" (stages 3-5) or "parturition 

 completed" (stages 6-7) (Fig. 5). The results indicated 

 a dome-shaped relationship with length wherein it ap- 

 pears that a higher proportion of the smaller and larger 

 females had not completed parturition. There were too 

 few observations from June to examine the transition in 

 more detail or to examine whether timing varied with 

 latitude within B.C. waters. 



Age observations from the commercial fishery indicate 

 that both sexes are 50% mature at about 10 years of 

 age and over 90% are mature at age 16 for females, 

 and age 13 for males (Table 5, Fig. 6). However, the 

 analysis was limited by the lack of young fish in the 

 samples. For example, there were only five 8-year old 

 and thirteen 9-year old females in the data set. Com- 

 parison of the age at maturity and partial recruitment 

 at age indicates that silvergray rockfish mature prior 

 to recruitment (Table 5, Fig. 7). 



