FISHERY BULLETIN: VOL. 71, NO. 2 



moon resembled those from 125 m and 145 m 

 at new moon. The calculated total for full 

 moon was 1.4 x that for new moon and the 

 calculated size-frequency curves differed con- 

 siderably. Both differences were due to larger 

 catches of 17- to 23-mm fish at full moon. Both 

 these data and the CT-IK comparisons indicate 

 that the IK missed some smaller fish in the 

 upper layers at new moon. If these differences 

 are real, they could in part account for the 

 apparent lower numbers and percents of ju- 

 veniles estimated in night series (see above). 



There were substantial numbers of juveniles 

 (<20 mm) in the June, July, and September 

 series with few in December 1970 and practically 

 none in March 1971. The percentages of mature 

 females with developed ova (Table 2) were 

 highest in March and June 1971 and significantly 

 lower in December 1970. These suggest that 

 spawning occurs principally in spring and 

 summer and that the juveniles have reached 

 trawlable size within a few months. 



Bolin'tchthys suprulciteralis 



No B. supralateralis over 53 mm long were 

 taken above the day depth range. Out of 15 

 such individuals, only 3 were caught during 

 deep night tows. These could well have been 

 contaminants and do not clearly confirm that 

 the larger individuals do not migrate. However, 

 out of 50 smaller fish caught at night, 10 were 

 caught in tows within the day depth range 

 suggesting that all sizes may not regularly 

 migrate. In the upper layers at night, fish less 

 than 20 mm occurred between 100 and 200 m, 

 but only two between 20 and 30 mm and none 

 over 30 mm were caught above 200 m. All sizes 

 appeared to occur throughout the day depth 

 range. 



The pooled IK size-frequency data indicated 

 that B. supralateralis spawns principally in 

 late summer and fall and that it may take at 

 least 2 years to reach maturity. There were 

 distinct, well-separated size classes in all but 

 the March 1971 series where only 11 fish were 

 caught. Small fish, 12-20 mm long, were most 

 abundant and made up the majority of the 

 catch in September and December 1970. It 

 appeared that this group was represented by 



24- to 35-mm individuals in June 1971. A 

 second year class was suggested by size classes 

 present only in the December 1970 and June 

 1971 series (41-53 mm and 47-59 mm, respec- 

 tively). A few fish larger than 60 mm were 

 caught in all series and may represent a third 

 year class. The only female with developed 

 ova was 88 mm long, almost the largest speci- 

 men taken. It is likely that such large individuals 

 avoid the trawl in addition to being rather rare. 



Ceratoscopelns ivarviingi 



The smallest C. warmingi regularly collected 

 in the trawl do not appear to regularly migrate. 

 At night, individuals 15-19 mm long were 

 caught both between 20 and 100 m and at 

 600-700 m. In June 1971, when these sizes 

 were most abundant, about two-thirds of the 

 juveniles remained at depth. There was no 

 indication that larger fish did not regularly 

 migrate. 



Within both day and night depth ranges the 

 size-frequency curves differed significantly. 

 Except during June 1971, at night few fish 

 over 40 mm were caught above 50 m and few 

 smaller individuals were caught below 75 m. 

 In the June 1971 series, however, large num- 

 bers of 15- to 19-mm fish were caught down 

 to 140 m, throughout most of the night 

 range. During the day, few individuals over 

 20 mm occurred at 600-700 m, and larger 

 individuals occurred principally below 750- 

 800 m. 



At night the percentage of females among 

 mature C. warmi)igi tended to decrease with 

 depth. In March 1971, when large numbers of 

 mature fish were caught at several depths, 89% 

 of the mature fish from 25 to 30 m were 

 females. At 50 and 80 m the value was 64% , 

 significantly lower. The value at 95 and 100 m 

 was 33%, and at 120 m was 31%. Both were 

 significantly lower than the values from shal- 

 lower tows. Similar, but nonsignificant, trends 

 were present in the September and December 

 1970 series. The only day series where suf- 

 ficient numbers of mature fish were collected 

 at several depths was in December 1970; there 

 were no trends or significant differences in 

 percentages of females. 



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