Harvey: Effects of El Nino events on consumption and egg production of Sebastes spp. 



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Figure 3 



Estimated energy consumption and egg production by S. mystinus at 

 the per-individual scale, under baseline conditions and for two cohorts 

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

 (A) Female energy consumption. (B) Male energy consumption. (C) Egg 

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



Effects of El Nino on fished cohorts 



Adding fishing mortality to the total mortality rate 

 applied in the per-recruit simulations caused changes in 

 the total energy consumption and egg production of S. 

 mystinus experiencing repeated El Nino events, in con- 

 strast to the baseline state. Under both El Nino regimes, 

 per-recruit consumption by both sexes increased slowly 

 as Z increased until it was nearly identical to the base- 

 line level for cohort A (Fig. 5A) or exceeded the baseline 

 for cohort B (Fig. 5B). The reason for this is that the 

 slower growth experienced during El Nino years meant 



that fish reached 200 mm (the size of recruitment into 

 the fishery) later and therefore were not as rapidly sub- 

 jected to fishing mortality as baseline fish. This extra 

 period of feeding prior to reaching 200 mm was sufficient 

 to equal or exceed the per-recruit energy consumption 

 level in the baseline model. 



In contrast, increased Z caused strong declines in 

 egg production, and that effect was exacerbated by the 

 frequency of El Nino years, as demonstrated by the 

 steeper decline in cohort B (Fig. 5B). Delayed matura- 

 tion caused by El Nino meant that many females were 

 removed by fishing before they were able to reproduce; 



