larvae can be important as they form such a very small fraction of the 

 plankton communityo Owing to the lack of data, it ignores competition 

 from other f onus » This is perhaps the greatest weaknesso 



It includes only the intrinsic influence on juvenile survival and 

 considers that the competition takes place between juveniles and post= 

 juveniles rather than within the juvenile category itself o (This particu= 

 lar selection has a back-ground of observation too extensive to describe 

 hereo It was suggested by the virtual disappearance of dominance of year 

 classes since intensification of sardine fishing took place.,) o T/ith ju" 

 veniles, alsOj the competition from other forms is ignored for the same 

 reason that it was among larvae. Howeverj utilization of data on predator 

 species of commercial fishes invites attention., 



The diagram opposite places the elements on a time~scale hori- 

 zontally, showing the approximate season and year from which the source 

 data are drawn and the approximate season and year in which the independent 

 would be expected to influence the dependent, variable^ recruitment. 

 Thus recruitment of the current season (n) would be estimated from the 

 (fully adjusted) sample of the current commercial fishing season. The 

 numerical value of this recruitment would be correlated withs (1) The 

 density of the post-juvenile population during the previous season (n-l) 

 as estimated from the (fully adjusted) sample of the previous commercial 

 fishing seasons I (2) the strength |or persistence) of northwesterly winds 

 during the spawning and developcaental portion of the second previous sea- 

 son (n-2) as estimated from weather records of that portion of the second 

 previous seasons and (3) the amount of spavining during the second previous 

 season (n-2) as estimated from the (fully adjusted) sample of the commer- 

 cial fishing season with, of course, due allowance for the percentage of 

 fish that are mature and the proportionality between s ize of spawner and 

 number of eggs spavmed.S/ The curved arrows connect source data with 

 the equivalent derived Trom ito The straight arrows with plus and minus 

 signs point from dependent variables to the independent one. It is as- 

 sumed that correlation between northwest winds and recruitment is positive 

 through its influence on upwelling and the attendant "fertilizing* of the 

 sea water. It could be negative (or curvilinear, ioe. positive in some 

 parts of its strength or persistence range and negative in others) through 

 its effect on drifting larvae away from the more favorable nursery grounds. 

 Which of these actually occurs would be revealed by the eorreiation analysis© 



The multiple correlation process indicates in the diagram. oppO" 

 site, three independent variables. If the correlations or regressions 

 are rectilinear, 6 degrees of freedom would be absorbed by the multiple 

 correlation process. It appears that data on the two intrinsic independent 

 variables will be derivable for eight seasons when the portion of the 

 program now in progress is completed. By that time, however^ two more 

 seasons will have elapsed and if they can be added, a series of ten seasons 

 will be available. The meteorological data^, if regular Weather Bureau 



"5/ Using approximate determinations published by Frances N. Clark, 1934. 



28 



