44 



Fishery Bulletin 105(1) 



Bay (P<0.02, R = 0.43, Fig. 5A), Ft. Bragg (P<0.001, 

 r=0.62), and Eureka (P<0.01, r=0.78). In 1998, Bodega 

 Bay was the only port where adult fish numbers were 

 significantly correlated (P<0.05, r=0.38. Fig. 5B) with 

 juvenile abundance. In 1999, Eureka was the only port 

 where adult fish numbers were significantly correlated 

 tP<0.05, i? = 0.35) with juvenile abundance. From the 

 1998 adult numbers in Bodega, 1985 was the largest 

 year class of adult yellowtail rockfish, which corre- 



6.0 r 

 5.0 

 i 4.0 



o 



2 3.0 



0) 



^ 2.0 



o 



I 10 



c 



g' 0.0 



_l 



-1.0 



86 88 



02 



-2.0 

 -200 



83 98 



-100 100 200 



Sea level anomaly in February 



300 



Figure 3 



An example of the log-transformed annual abundance index for blue 

 rockfish tSebastes mystinus) and average sea level anomaly in February 

 for each year of the survey (198.3-2003). Numbers represent individual 

 years. Dashed lines represent the zero line for both axes. 



sponded to the highest index for juvenile yellowtail 

 rockfish (Fig. 5B). 



Discussion 



The 21-year time series of juvenile rockfish abundance 

 allowed us to examine long-term change in recruitment 

 of commercially and recreationally important species 

 off the coast of California. The year-to-year 

 variability in recruitment likely relates to 

 variability in year-class strength of the 

 population entering the fisheries. The syn- 

 chrony in recruitment variability among 

 the three rockfish species indicates that 

 similar environmental processes affect the 

 abundance of all three species. By exam- 

 ining oceanographic variables, we deter- 

 mined that sea level anomaly and nearshore 

 temperatures in February and March were 

 important influences on juvenile rockfish 

 abundance. 



Year-to-year variability in young rock- 

 fish abundance has been documented in 

 other studies off the west coast of the 

 United States. Yoklavich et al. (1996) 

 found a twenty-fold increase in the abun- 

 dance of pelagic larval rockfishes off cen- 

 tral California in 1993 compared to num- 

 bers obtained during a similar time period 

 in 1992. They attributed this difference 

 to increased offshore transport and pos- 

 sibly lower predation rates. Moser et al. 

 (2000) observed large fluctuations in annu- 

 al larval rockfish abundance off southern 

 California from 1951 to 1998, which was 

 attributed to the reproductive output of 

 each species and oceanographic variables. 

 Mearns et al. (1980) determined that the 

 variability in recruitment of juveniles was 

 the major source of seasonal and annual 

 fluctuations in rockfish catches for strip- 

 etail and calico rockfish (S. dallii). Mat- 

 thews (1989) observed that recruitment 

 levels varied between years for three spe- 

 cies of rockfishes recruiting to nearshore 

 habitats. Ainley et al. (1993) discovered 

 a three-fold difference in pelagic juvenile 

 rockfish abundance in seabird diets in cen- 

 tral California between similar periods in 

 1985 and 1986, and they attributed this to 

 cross shelf advection of larvae in January 

 and February. Ralston and lanelli (1998) 

 reported a large variability in juvenile bo- 

 caccio abundance over a 13-year period 

 and attributed some of this variability to 

 El Niiio events. 



Year-class strength was likely estab- 

 lished in the period from February through 

 March during the larval stage of the three 



