Lyo psetta exilis 



10 

 10 

 10 



40 

 50 



20 

 10 



40 

 50 



20 

 10 

 10 

 



269 18 28 37 46 56 65 74 93 

 STATIONS 



Stenobrachius leucopsarus 



50r— 



50 — 



50 — 



200 — 



150- 



100- 



50- 



350 — 



300- 



250- 



200- 



150- 



100- 



50- 



200 — 



150- 



100- 



50- 



— 



m 1 1 1 1 1 T 



FEB . 



MAR 



APR 



MAY 



JUN 



JUL 



-m — I — I — I — l — l — T — T T 



269 18 28 37 46 56 65 74 93 

 STATIONS 



Gly ptocephalus zachirus 



E D 

 5 5 







10 

 15 

 10 

 10 

 30 

 20 

 10 

 30 

 20 

 10 

 50 

 40 

 30 

 20 

 10 

 



STATIONS 



Tarletonbeama crenularis 



FEB 



MAR 



j__L 



APR 



MAY 



J 



JUN 



JUL 



tti — i — i — i — T — i — T ' 



269 18 28 37 46 56 65 74 

 STATIONS 



93 



FISHERY BULLETIN: VOL. 75, NO. 1 



Sebastes spp 



50 



50 



150 



100 



50 





 350 



300 



250 



200 



150 



100 

 50 



50 



50 







2 69 18 28 37 46 56 65 74 

 STATIONS 



Protomyctophum thompsoni 



10 



< 

 > 



cr 



o 



5- 



STATlONS 



FIGURE 8. — Distribution patterns offish larvae in the offshore assemblage (stations 37 to 111) during months of peak abundance in 



1971. Abundances are monthly means. 



and cephalopods caught in plankton nets and 

 mid-water trawls was also low at this station 

 compared with offshore stations (Pearcy 1976). 

 Interestingly, this region is located over midshelf 

 where water depth is about 95 m rather than at the 

 shelf break. 



Explanations for this observed phenomenon are 

 severalfold. Certainly peak concentrations of 

 coastal and offshore larvae are related in part to 

 the spawning location of adults. Most larvae that 

 are taken in plankton collections are small, have 

 not been in the water column for an extended 

 period of time, and thus occur near the area in 

 which they were spawned. Possibly few adult fish 

 spawn near 28 km offshore although data to 

 substantiate this are not available. 



Circulation patterns also help to explain the 

 observed larval distributions. General seasonal 

 trends of currents over the continental shelf, 

 shoreward of the California Current, have been 

 described by Smith et al. (1971), Wyatt et al. 



(1972), Huyer (1974), Smith (1974), Huyer et al. 

 (1975), and others. The predominant currents, 

 those of greatest velocity, are alongshore. In 

 winter, October through February, when winds 

 are predominantly from the southwest, the main 

 flow is northward (Davidson Current) at all 

 depths, with an onshore drift component at the 

 surface. A strong alongshore flow occurs within 28 

 km of the coast. In summer, May through August, 

 winds are predominantly from the northwest and 

 the main current flow is southward, with an 

 offshore drift component at the surface. South- 

 ward flow is greatest in a coastal jet located 15 to 

 20 km offshore. In spring, deeper water (bottom 

 third of the water column) flows south but at a 

 slower speed than the surface water (upper third of 

 the water column). In summer, this deeper water 

 flows northward. There is also a shoreward drift 

 component in these deeper and intermediate 

 waters which produces upwelling, a process which 

 taken place mainly within 10 to 20 km of the coast. 



140 



