FISHERY BULLETIN: VOL. 75, NO. 1 



TABLE 4. — Length-frequency distributions of Microstomas pacificus larvae collected during vari- 

 ous months. Numbers in parentheses denote larvae caught in bongo nets; numbers without 

 parentheses denote larvae caught in mid-water trawls. 



their absence in the spring suggest that some 

 larvae may settle out in less than a year. Con- 

 versely, the presence of large larvae (>50 mm) 

 during June, shortly after the end of spawning 

 season (Table 5), suggests that some larvae may be 

 pelagic for over a year, like some Dover sole lar- 

 vae. Powles and Kohler (1970) believed that G. 

 cynoglossus larvae in the North Atlantic are also 

 pelagic for the first year of life. 



Petrale sole larvae were only found during 4 

 mo, March-June (Figure 4). No distinct progres- 

 sion of stages was apparent, though stage I lar- 

 vae were only collected in March and April and 

 stage IV only in June. Petrale sole spawn in winter 

 and early spring, November to April in the 

 northeastern Pacific (Harry 1959; Porter 1964; 

 Alderdice and Forrester 1971), so our limited data 

 indicate an egg and larval period of about 6 mo. 



INSHORE-OFFSHORE AND 

 NORTH-SOUTH DISTRIBUTION 



Both Dover and rex sole larvae were widely 

 distributed offshore. All three species of flounders 

 are considered to have "offshore" larvae by 

 Richardson and Pearcy (1977). 



Bongo nets collected Dover sole larvae at all but 



the 6-km station (Table 6), although the larvae 

 were most frequent and abundant at the offshore 

 stations (56-111 km), where 84.8% of all larvae 

 were taken. Peak abundance occurred at the 

 111-km station. Rex sole were taken at all stations 

 but were more abundant offshore (46-111 km) 

 where 80.5% of all larvae occurred. Peak 

 abundance was at 46 km. One specimen of petrale 

 sole was taken 56 km offshore. 



Largest mid-water trawl catches of Dover sole 

 larvae were usually made in oceanic waters more 

 than 46 km offshore along all four station lines 

 (Table 7). Some larvae were taken as far as 550 km 

 offshore. Rex sole larvae were most common at the 

 28- to 83-km stations over the outer shelf and 

 slope, but were also captured farther offshore. The 

 farthest offshore a rex sole larva was collected was 

 195 km. Petrale sole larvae were collected from 2 

 to 120 km from the coast. About half the petrale 

 larvae were caught 83-120 km offshore. 



Lengths of larvae at varying distances from the 

 coast provide clues to inshore-offshore dispersal. 

 In the bongo net transect data, Dover sole larvae 

 < 11 mm were collected at all stations except 6 km, 

 but the greatest numbers of small larvae were at 

 the 93- and 111-km stations. Larger larvae (11-26 

 mm) occurred only at stations 56 to 111 km 



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