PEARCY ET AL.: DISTRIBUTION AND DURATION OF PELAGIC LIFE OF LARVAE 



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FIGURE 3. — The relative abundance of each stage of rex sole 

 larvae in bongo transect and mid-water trawl collections during 

 all months. 



offshore. Similarly, rex sole larvae <11 mm were 

 taken at all stations but greatest numbers oc- 

 curred at the 46-km station. All but 2 of the 29 rex 

 sole larvae 2=11 mm (11-67 mm) were taken at 

 stations 37 to 111 km offshore. These trends 

 suggest that larvae >11 mm of both species are 

 most common in waters beyond the continental 

 shelf In the bongo net grid samples, Dover and rex 

 sole larvae, which were mostly smaller than 10 

 mm SL, were widely distributed. They were taken 

 at all distances 2 to 56 km from the coast, but 

 always in low numbers. Mean numbers per 10 m 2 

 sea surface were less than 0.30 for Dover sole lar- 

 vae and 0.70 for rex sole larvae. 



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FIGURE 4. — The relative abundance of each stage of petrale sole 

 larvae in bongo transect and mid-water trawl collections during 

 all months. 



No obvious trend of increasing mean size of 

 large Dover or rex sole larvae with distance 

 offshore was apparent from mid-water trawl 

 collections. However, the eight rex sole larvae <30 

 mm SL in mid-water trawl collections were all 

 captured between 9 and 83 km offshore. 



In mid-water trawl samples, the ratio of Dover 

 larvae =£30 mm to those larvae >30 mm during 

 the summer (May-September) was 15:1 and 6:1 at 

 stations inshore and offshore of 83 km, respec- 

 tively. This indicates a preponderance of "small- 

 er" larvae over the shelf and slope, probably a re- 

 sult of spawning the previous winter. During 

 winter (October-April) these ratios were 1:2 

 inshore and 2:1 offshore of 83 km, reflecting a 

 greater proportion of large larvae during the win- 

 ter especially over the shelf and slope where they 

 will settle. 



North-south trends were not as obvious. In the 

 bongo grid samples, Dover sole larvae were taken 

 on 9 of the 12 lines with the mean number 

 per 10 m 2 on each line always less than 0.26. Rex 

 sole larvae were taken on all 12 lines. Mean 

 number per 10 m 2 on each line ranged from 0.24 to 

 1.26 with the greatest numbers occurring over 

 Heceta Bank. One petrale sole larva was taken 37 

 km offshore just north of Cape Blanco. In the 

 mid-water trawl samples the mean catch per tow 

 of Dover sole was about the same along the three 

 northern station lines, and was about twice as 



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