Abstract: Based on the samples of Berryteuthis magister shevtsovi collected in the Sea of Japan in December 2018, fishery biological characteristics were examined, including morphology, mantle length, body weight, sex maturity, stomach stage and fatness index. The result showed that the mantle length and body weight of B. magister shevtsovi in dominant group were 100-120 mm and 30-70 g respectively, while the mean values of fin length and width were (58.36±5.81) mm and (90.44±6.89) mm, respectively. For the relationship between body weight and mantle length, condition factor a and allometric growth factor b were 0.0007 and 2.3934, respectively, with mantle length growing faster than body weight. The maturation of gonads was dominated by individuals from stage I and II. When the mantle length was lower than 110 mm, the stomach stage was mostly at grade 1-2. The proportion of individuals with stomach stage at grade 3-4 increased when the mantle length was higher than 110 mm. The fatness index decreased with increasing mantle length. Our results provide reference for the future research on population identification, life history, development and utilization of B. magister shevtsovi.

Key words: Berryteuthis magister shevtsovi, fishery biology, mantle length, body weight, stomach stage, sex maturity.