FISHERY BULLETIN: VOL. 70, NO. 3 



SOUTH BAJA 

 BAja CALIF, 



SOUTHERN CALIF, 



CENTRAL CALIF 



Figure 10. — A time-series comparison of the annual total regional census estimates of 

 anchovy larvae as grouped by coastal section. The highest line (solid circle) is comparable 

 to the quarterly average of "A" in Figure 9. The space between the top line and the 

 line with open dots represents the contribution to the total by stations in the south Baja 

 section. The space between the open dot line and the line connecting the solid squares 

 represents the contribution of the Baja California section to the total. The space between 

 the line connecting solid squares and the line connecting open squares represents the 

 contribution of the southern California section. The space between the lines connecting 

 open squares and the abscissa represents the contribution of the central California section 

 to the total. For relative areas of the sections refer to Table 3 and Figure 2. 



patches covering 0.1 of the area, the chance of 

 encountering two patches is 0.01; with patches 

 covering 0.9 of the area, the chance of encounter- 

 ing two patches simultaneously is roughly 0.8. 

 In the southern California inshore and offshore 

 regions, the proportion of positive stations is re- 

 lated to the number of larvae per positive sta- 

 tion in the following way: 



logio Ni 

 \og10N2 

 logio N's 



3.20 Pi — 0.218 

 2.13 P2 + 0.748 

 2.32 P3 + 0.573 



t = 11.17 37 df 

 t = 9.95 37 df 

 t = 14.40 76 df 



where Ni = number of larvae per 10 m^ per 

 positive station in the tth region, 

 when i = 1 = southern California 

 inshore region, when i = 2 = 

 southern California offshore re- 

 gion, when { = 3 the inshore and 

 offshore regions are combined; 



Pi = proportion of positive stations in 

 winter and spring in offshore (i = 

 2) or inshore areas (i = 1), or 

 both (i = 3). 



If the patchy model applies, this set of equations 

 is good only for the CalCOFI standard tow, in 

 these two regions. For example on theoretical 

 grounds, if the standard tow were to sample 

 under 20 m^ rather than the average 3 m- as at 

 present, one would expect the proportion of pos- 

 itive tows to rise and the number per positive 

 tow to decrease for any given average of anchovy 

 larvae per total unit area. 



In addition to an increasing proportion of 

 positive tows in traditional spawning areas and 

 increasing numbers of larvae per positive tow, 

 the southern California seaward region is an ex- 

 ample of a new spawning area being invaded in 



868 



