CAJ | 학술논문

种群问题是渔业生物学研究的基础。根据2011年春季罩网渔船调查数据，研究了南沙海域鸢乌贼（ Sthe-noteuthis oualaniensis）的种群组成、胴长分布、雌雄比例、性腺发育等种群结构特征。结果显示：1）南沙海域存在中型和微型2个鸢乌贼种群，分别占渔获总尾数的88.92%和11.08%，微型种群渔获量少但也遍布整个调查海域；2）中型和微型种群渔获胴长范围分别为69~231 mm和51~125 mm，2个种群雌性的平均胴长均大于雄性；3）中型和微型种群中雌性个体分别占48.48%和61.88%，2个种群不同胴长组性比随着胴长的增加变化规律相似，即由开始阶段雌雄基本接近，到雄性个体占优，再到雌性个体占优，直至全部为雌性；4）微型种群性腺发育早于中型种群，雄性个体性腺发育早于雌性个体，雌、雄初次性成熟胴长（ ML50%）中型种群分别为179.7 mm和125.6 mm，微型种群分别为94.8 mm和81.1 mm。鸢乌贼雌雄比例的变化与雄性个体的生长发育密切相关。
충군문제시어업생물학연구적기출。근거2011년춘계조망어선조사수거，연구료남사해역연오적（ Sthe-noteuthis oualaniensis）적충군조성、동장분포、자웅비례、성선발육등충군결구특정。결과현시：1）남사해역존재중형화미형2개연오적충군，분별점어획총미수적88.92%화11.08%，미형충군어획량소단야편포정개조사해역；2）중형화미형충군어획동장범위분별위69~231 mm화51~125 mm，2개충군자성적평균동장균대우웅성；3）중형화미형충군중자성개체분별점48.48%화61.88%，2개충군불동동장조성비수착동장적증가변화규률상사，즉유개시계단자웅기본접근，도웅성개체점우，재도자성개체점우，직지전부위자성；4）미형충군성선발육조우중형충군，웅성개체성선발육조우자성개체，자、웅초차성성숙동장（ ML50%）중형충군분별위179.7 mm화125.6 mm，미형충군분별위94.8 mm화81.1 mm。연오적자웅비례적변화여웅성개체적생장발육밀절상관。
Research on fish population is foundamental for studies on fishery biology. Based on the survey data of purpleback flying squid( Sthenoteuthis oualaniensis)collected by Chinese falling-net vessels in Nansha area of the South China Sea during April to May in 2011,we studied the population composition,mantle length distribution,sex ratio and maturity of S. oualaniensis in that area. The results show that two populations of S. oualaniensis existed in Nansha area. The medium-form and dwarf-form individuals accounted for 88. 92% and 11. 08% of the total catches,respectively. The dwarf-form population was less abundant but occurred throughout the sur-vey area. Mantle length( ML)of S. oualaniensis ranged from 69 mm to 231 mm for medium-form population and from 51 mm to 125 mm for dwarf-form population,respectively. The average ML of females was higher than that of males for two populations. The females accounted for 48. 48% and 61. 88% in the medium-form and dwarf-form populations,respectively. The variation of sex ratio by differ-ent ML groups was similar for two populations. The sex ratio of females to males was approximately the same among young squids with increasing ML,i. e. ,males were first dominant,then were females and finally there were all females. The maturity stage of dwarf-form population was higher than that of medium-form population. The maturity stage of males was higher than that of females for two populations. By fitting Logistic function,the MLs at first maturity for females and males of medium-form population were 179. 7 mm and 125. 6 mm,respectively;and those for females and males of dwarf-form population were 94. 8 mm and 81. 1 mm,respectively. It is suggested that the variation of sex ratio is closely related to the growth and maturity of males.