Arkhipkm et al.: Distribution, stock structure, and growth of Berryteuthis magister 



21 



E 



c 

 (0 



2 



400 

 360 

 300 

 260 

 200 

 160 

 100 



400 

 360 

 300 

 250 

 200 

 160 

 100 

 60 



400 

 350 

 300 

 250 

 200 

 150 

 100 



400 

 360 



luu 

 250 

 200 

 150 

 100 

 50 



50 100 150 200 250 300 350 400 450 600 



50 100 150 200 250 300 360 400 450 600 



50 WO 160 200 260 300 350 400 460 600 



60 WO 150 200 250 300 360 400 450 500 



400 

 350 

 300 

 260 

 200 

 160 

 100 



fTBRUARY 

 hatch 



400 T 

 350 

 300 

 250 

 200 

 160 

 100 

 60 



400 



350 

 300 

 260 

 200 

 160 

 100 



400 

 360 

 300 

 260 

 200 

 160 

 100 



50 WO 150 200 260 300 350 400 450 500 



60 WO 160 200 250 300 360 400 450 500 



50 WO 150 200 250 300 350 400 450 600 



60 WO 160 200 250 300 350 400 450 600 



400 

 360 

 300 

 260 

 200 

 160 

 100 

 60 



MARCH 

 hatch 



50 WO 160 200 260 300 350 400 460 600 



400 

 360 

 300 

 260 

 200 

 |60 

 100 



60 WO 160 200 250 300 360 400 450 600 



60 WO 150 200 260 300 350 400 460 600 



400 



360 

 300 

 260 

 200 

 160 

 100 

 60 



DECEMBER 

 hatch 



V* 



60 WO 160 200 250 300 350 400 450 600 



Age (d) 



Figure 12 



Length-at-age data for males of Berryteuthis magister in the western Bering Sea. 



Maturation with growth Males and females of vari- 

 ous month classes matured at different sizes and ages 

 (Figs. 12 and 13). In our samples, juveniles were 

 mainly from a winter-hatched group, mature speci- 

 mens at different substages of maturity stage 5 were 

 from a summer-hatched group, and squid of various 

 stages of maturation and maturity were from a fall- 

 hatched group. Thus, it was reasonable to analyze 

 group rates of B. magister maturation by using the 

 data on both sexes from the fall-hatched group and 

 females from the summer-hatched group (because all 



summer-hatched males were already mature during 

 the period studied). 



Ages at various maturity stages (maturity rates) 

 differed between the sexes (Fig. 15). Males began ma- 

 turing earlier than females. All males were at matu- 

 rity stage 1 at 210 days. However, at 240 days al- 

 most half of them reached maturity stage 2 (a few 

 specimens already being mature). By 300 d, the pro- 

 portion of immature and maturing males (maturity 

 stages 3 and 4) was greatly reduced, with most of 

 the males already mature. At ages older than 310 d, 



