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Fishery Bulletin 91(2), 1993 



These stocks were chosen because they have each sup- 

 ported major fisheries and have been studied suffi- 

 ciently well so that long time-series of stock and re- 

 cruitment data are available. These coastal pelagic 

 species also form a conspicuous part of the California 

 Current ecosystem. 



Explanatory data (data on the environment) included 

 time-series of two types: variables related to climate, 

 and variables reflecting contaminant loadings or other 

 potential human impacts. These data were subjected 

 to a number of stages of preliminary processing, in- 



cluding two principal component analyses, to compute 

 two sets of derived variables (principal components) 

 from a larger number of potential explanatory 

 variables. 



Data on fish abundances 



Stock and recruitment data on northern anchovy (Table 

 1, Fig. 1) were obtained from Table 8 of Methot ( 1989), 

 who derived his estimates from fishery statistics and 

 research survey data. For spawning-stock size, we used 



