I/) 



z 



Ui 



2 

 o 



LlI 



a. 



CD 



2 

 r> 

 z 



15 

 FEBRUARY 



20 25 I 



i 



10 15 20 25 

 MARCH 



30 I 



10 15 20 25 

 APRIL 



30 



10 15 

 MAY 



Figure 4. -Distribution of dates of first increment formation for A noplopam-a fimbrin, determined by back-calculations using 



age and collection date. 



Phillips (1958) defined the peak spawning season off 

 California to be January-February. Bell and Gharrett 

 (1945) suggested that the spawning season was 

 around December off Washington based upon fisher- 

 men's observations and the presence of spent 

 females in January. Farther north, Thompson (1941) 

 observed ripe females and fertilized eggs in March at 

 Cape St. James (lat. 51°45'N). More recent work has 

 shown that the spawning season off British Columbia 

 occurs in January to February with the peak of 

 spawning in February (Mason et al. 1983). 



Our observed growth rates for A. fimbria during 

 the first 6 months of life are high for a temperate- 

 subarctic species, yet are clearly below the potential 

 growth rate as shown in the laboratory (Shenker and 

 011a footnote 3). Similar but lower laboratory growth 

 rates (1.2 mm/d) were observed for 100 to 150 mm 

 juvenile red hake, Urophycis chuss, by Luczkovich 

 and 011a (1983). Both of these species contrast mark- 

 edly with larval juvenile growth in other taxa. Boeh- 

 lert and Yoklavich (1983), for example, summarized 

 laboratory and field growth measurements for 13 

 species in the genus Sebastes and noted growth rates 

 ranging from 0.092 to 0.590 mm/d. Young sablefish 

 thus utilize the neustonic and pelagic environment to 

 rapidly reach sizes at which migration to the benthic 

 adult habitat occurs. 



Acknowledgments 



This work was supported by the Northwest and 

 Alaska Fisheries Center, National Marine Fisheries 

 Service, Seattle, WA, through contracts 81-ABC- 

 00192-PR6 and 83-ABC-00045. We thank A. W. 



Kendall, Jr., W. G. Pearcy, and J. Shenker for pro- 

 viding specimens for this study, Chris Wilson for 

 technical assistance with otolith preparation, and R. 

 Methot for reviewing the manuscript. 



Literature Cited 



Barkley, R. a. 



1972. Selectivity of towed-net samplers. Fish. Bull., U.S. 70: 

 799-820. 

 Beamish, R. J., and D. E. Chilton. 



1982. Preliminary evaluation of a method to determine the age 

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Beamish, R. J., G. A. McFarlane, and D. E. Chilton. 



1983. Use of oxy tetracycline and other methods to validate a 

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Bell, F. H., and J. T. Gharrett. 



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Boehlert, G. W., and M. M. Yoklavich. 



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480 



