20 



Fishery Bulletin 94( 



1996 



Males 



100 150 200 250 300 



Mantle length (mm) 



B 



3 5 

 3 



25 

 2 



1 5 



Females 



n- 197 



400 500 



Males 



Figure 1 1 



Statolith growth in Berryteuthis magister. Relationship between (A) total length and mantle length and (B 

 length and number of second-order increments on the statolith (age in days). 



longed to different month classes, differed in size, 

 and represented different sections of the group 

 growth curves. There were only a few data on spring- 

 hatched B. magister, especially for males (Figs. 12 

 and 13). This prevented the comparison of growth 

 rates of the same-age squids from, for example, win- 

 ter- and summer-hatched animals. 



The growth curve of mantle length versus age was 

 best fitted with a logistic growth curve (Table 5). 

 Males and females grew at the same growth rate until 

 210-240 d (Fig. 14, Aand B). Thereafter, males grew 

 more slowly than females and at age 390 d their mean 

 ML was approximately 50 mm less than that of females. 



The relationship of mantle length to body length 

 did not show any pattern of sexual dimorphism (Fig. 

 14C). The power coefficient was less than 3 (2.62), 

 demonstrating the relative slenderness of the body 

 of large-size squid. According to calculated weight 

 growth curves, females began to exceed males in body 



weight later than in mantle length (at age 270 d) 

 (Fig. 14D). 



Berryteuthis magister is a rather slow-growing 

 squid. Daily growth rates (DGR) in ML were low in 

 juveniles (0.27—0.35 mm-d -1 ), reached their maxi- 

 mum values in males at ages 180-210 d (ca. 0.9 

 mm-d" 1 ) and in females at ages 210-270 d (1.05-1.08 

 mm-d ' ), then gradually decreased to juvenile levels 

 for females and fell even lower for males (Fig. 14E). 

 Juvenile DGR in BW were very low (0.02-0.06 gd ' ). 

 However, they quickly increased with age and at- 

 tained maximum values at older ages in both males 

 and females, 270-300 d and 300-330 d, respectively 

 (Fig. 14F). The instantaneous rate of growth (G) in 

 ML was maximum in early juveniles (0.0118—0.0124), 

 then gradually decreased to the age of 420 days, in 

 males to a greater extent than in females (0.0007 

 and 0.0012, respectively). Calculated values of G in BW 

 were similar to the trend in ML (Fig. 14, G and H). 



