Castillo et al.: Recruitment variation in Eopsetta jordani 



489 



X 



m 

 Q 



Z 



M 



(31 



Z Li. 

 HI O 



OC v> 



Si 



600 



500 



400 



300 



200 



100 



AREA 2B 

 R'= 0.30 

 P < 0.05 



150 



100 



- 50 



50 



OFFSHORE EKMAN TRANSPORT ANOMALY 

 (METRIC TONS/SECOND PER 100-m COAST) 



Figure 10 



Relations between year-class strength of petrale 

 sole, Eopsetta jordani , in Pacific States Marine 

 Fisheries Commission areas 2B and 3A and 

 mean offshore Ekman transport anomaly off 

 Oregon from January to March. (Regression 

 parameters are shown in Table 3. 1 



o 



2 £ 



LU ts> 



X u- 



K u. 



!/) O 



</) 8 



tn z 



< < 



d s 



< ~ 



UJ 



> 



- 2 - 1 1 2 



SEA SURFACE TEMPERATURE ANOMALY ( °C) 



Figure 12 



Relation between year-class strength of petrale 

 sole, Eopsetta jordani , in Pacific States Marine 

 Fisheries Commission Area 3A and mean win- 

 ter sea surface temperature anomaly off Oregon- 

 Washington (December-February). (Regression 

 parameters are shown in Table 3.) 



transport during winter (Ketchen and Forrester, 

 1966). The analyses in Area 3A are also consistent 

 with an association between temperature and sur- 



2 



600 



500 



400 



AREA 2B 

 R' = 0.386 



gi 



o 



Z u. 

 uj o 



DC tn 

 Wo 



2§ 



H 200 



100 

 1200 



1000 



2 



800 



600 



400 



200 



AREA 3A 



= 0.399 

 0.05 



1969 1958 



■0.2 -0.1 0.0 0.1 



SEA LEVEL ANOMALY (m) 



0.2 



Figure 1 1 



Relations between year-class strength of petrale 

 sole, Eopsetta jordani, in Pacific States Marine 

 Fisheries Commission areas 2B and 3A and win- 

 ter mean sea level height anomalies. (Regression 

 parameters are shown in Table 3. ) 



vival of early life stages of petrale sole (Ketchen and 

 Forrester, 1966; Alderdice and Forrester, 1971 ). Con- 

 sidering the discharge of the Columbia River into 

 Area 3A and the stenohaline condition of eggs and 

 larvae in this species, possible salinity- YCS associa- 

 tions may be overridden by cross-shore and along- 

 shore advection and sea temperature. 



Recruitment strength of petrale sole was correlated 

 between areas 2B and 3A(r=0.82, P<0.01). However, 

 the highest determination coefficient for regression 

 models ofYCS on environmental factors was obtained 

 in Area 3A. Although the proportion of variation in 

 YCS explained by second-order polynomial regres- 

 sions was significant for both offshore Ekman trans- 

 port and sea level height, filtered series suggest that 

 year-to-year variation in YCS were better explained 

 by the former. Unlike Area 3A and off British Co- 

 lumbia (Ketchen and Forrester, 1966), no regression 

 models of YCS on sea surface temperature were sig- 

 nificant or marginally significant in Area 2B. The 

 higher positive temperature-YCS association for Area 

 3A compared with Area 2B is consistent with tem- 

 perature differences between areas (Appendix A). 

 These observations suggest a latitudinal effect of tem- 

 perature on the recruitment of petrale sole, that is, 

 higher recruitment toward the poleward range of the 



