SARDINE EGGS 

 GRIDS l-V 



I - 30 

 31-300 

 301-3,000 

 over 3,000 



Figure 2. Sardine eggs: distribution and relative abundance on Grids I - V, April 18-23, 1952. 



species (anchovy, jack mackerel. Pacific 

 mackerel, hake, and rockfish) were relatively 

 few in numbers (table 3). Tables 4 through 7 

 are records of all hauls containing larvae 

 of sardine, anchovy, jack mackerel, and Pacific 

 mackerel reported by numbers per size class 

 per station. Tables 8 and 9 are records of all 

 hauls containing hake and rockfish larvae re- 

 ported by numbers per station. 



Noncommercial species of fish larvae (table 

 3) were best represented by the deep-sea 

 smelt, Leumglossus stilbius, and the lantern- 

 fish, Lampanyctus mexicanus, which together ac- 

 counted for about 80 percent of "other fish 

 larvae" collected on the grid, drogue, and 

 anchor stations. These are reported by num- 

 bers per station in tables 10 and 11. The dis- 

 tribution diagrams for these larvae on the grids 

 (figs. 4 and 5) show that the greater numbers 

 were usually located offshore. This may indi- 

 cate one of two types of distribution: First, 

 that each of these species was normally 



greater in numbers offshore (as the sardine 

 larvae were inshore, fig. 3); or second, that 

 these greater offshore numbers were an indi- 

 cation of diurnal migration of the larvae that 

 made them more available to the net at night, 

 as in the case of other plankton discussed 

 below. The latter seems more probable in 

 view of the findings of Ahlstrom (1959) who 

 reported that these two species showed 

 evidence of diurnal migration in replicate (day 

 and night) vertical distribution series. He 

 found that 5.0 times as many Leumglossus 

 stilbius larvae and 3.6 times as many 

 Lampanyctus mexicanus larvae were caught by 

 night as by day. 



Differences in day and night collections on 

 the grid stations were determined by weighting 

 the numbers of larvae per haul in the daily 

 collections and finally by 5-day ratios based 

 on larvae per haul for all groups of data; five 

 grids and 5 days each on drogue and anchor 

 stations. Each grid was divided into night 



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