78 



Fishery Bulletin 103(1) 



Baseline 



--■ — Cohort A 

 —a— Cohort B 



10 15 



D 



10 



15 

 Age (y) 



20 



25 



30 



Figure 4 



Estimated energy consumption and egg production by S. mystinus at 

 the per-recruit scale, under baseline conditions and for two cohorts (A 

 and B) in which El Nino events occurred every three to seven years. 

 (Al Female enrgy consumption. (B) Male energy consumption. (C) Egg 

 production. (Dl Timing of El Nino events for cohorts A and B. 



furthermore, those that escaped fishing had lower fe- 

 cundities because of their smaller size and reduced 

 egg production because of the number of El Nino years 

 experienced. 



Sensitivity analysis 



Based on the RPSS analysis, sensitivity of rockfish 

 bioenergetics models to parameter variation was a func- 

 tion of sex, size, and the CV of the parameter set. When 

 CV = 2%, the model was most sensitive to respiration 



parameters in Equation 2 (particularly RB, RQ, and 

 RTO) and to ED, although the rank order varied slightly 

 by sex (Fig. 6, A and B). The sum of the RPSS cv=2fJ 

 for all parameters was >0.99 for both the male and 

 female models. This result implies that energy consump- 

 tion responded linearly to parameter variation because 

 summed RPSS values scale from to 1, with 1 implying 

 a linear response to parameter perturbation (Bartell et 

 al., 1986). When CV increased to 10%, the rank order 

 of parameter sensitivity changed slightly, although res- 

 piration parameters and ED remained most important 



