54 



Fishery Bulletin 104(1) 



2000 



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Figure 6 



Density profiles (exponential bubble ploti for Loligo opalesceus paralarvae in the 

 Southern California Bight, February 1999-2003 (shaded area of Fig. 1). Size of 

 circles corresponds to number of paralarvae/1000 m-' seawater sampled. Data 

 for 1999-2001 reprinted with permission from Springer-Verlag, originally in 

 Zeidberg and Hamner (2002) Mar. Biol. 141(1):111-122. Data from all tows were 

 averaged to obtain a paralarvae density index (PDI) for each year, lower right. 

 1999 La Niiia (cold) and 2002 El Nifio (warm) events are labeled above bars in 

 the index. Note the lack of any sample sites within 8 km of shore or with >100 

 paralarvae/1000 m-= in 1999. 



ture squid and fail cannot be tracked with this method, 

 and squid that are not harvested commercially are not 

 accounted for in this report. Loligo opalescens reproduces 

 by aggregating from small, foraging groups of hundreds 

 of individuals to groups of millions of individuals. It is 

 possible, therefore, that a large decrease in biomass 

 can be masked by a larger percentage of the population 

 aggregating in seemingly similar-size spawning masses. 

 Such species are vulnerable to highly mobile fisheries 

 (Oostenbrugge et al., 2002). 



Trends in the fishery 



The fishery for market squid (Loligo opalescens) has 

 increased in all parts of the study area since 1983 

 because of an increase in demand for calamari inter- 

 nationally and because of the collapse of other fisheries 

 both within and outside California waters. The major- 

 ity of fishing activity has shifted from Monterey Bay to 

 the Southern California Bight since the 1980s. Fishing 

 activity in the bight experienced a second increase in 



