东太平洋赤道公海茎柔鱼生物学特性

Study on the Biological Characteristics of Jumbo Flying Squid Dosidicus gigas in the High Seas Nearby the Equator of Eastern Pacific

根据2013年4-6月在赤道公海探捕期间采集茎柔鱼样本,研究赤道公海茎柔鱼渔业生物学特性。结果表明,不同性别、不同月份,茎柔鱼胴长和体质量组成不同。雌、雄性样本的胴长范围分别为93-495 mm和94-406 mm,优势胴长组分别为260-340 mm和240-320 mm,分别占样本总数72.53%和70.26%;雌、雄性样本体质量范围分别为25-3 900 g和33-2170 g,优势体质量组分别为400-1 200 g和200-1 000 g,分别占样本总数82.71%和87.82%。雌、雄性茎柔鱼净体质量比例分别介于31.69%-80.51%和37.05%-81.35%之间,平均值分别为60.45%和62.73%。协方差分析表明,茎柔鱼胴长与体质量、胴长与净体质量的生长均存在性别间差异,胴长与体质量的生长都最适合用幂函数表示,而胴长与净体质量的生长,雌、雄性样本分别最适合用幂函数和指数函数表示。不同月份茎柔鱼性别比例构成不同,4月、5月和6月性别比例分别为1.87∶1、1.61∶1和1.17∶1,全部样本的性别比例为1.61∶1。不同月份茎柔鱼性腺成熟度的组成不同。不同性别、不同月份间茎柔鱼胃含物等级组成存在差异。

The biological characteristics were studied based on the samples of Dosidicus gigas collected by Chinese squid jig fishing fleets during April to June of 2013 in the high seas nearby the equator. The result indicated that the mantel length （ML） and body weight （BW） composition were different according to different genders and months. The mantle length of females ranges from 93 mm to 495 mm with a higher concentration in 260mm to 340mm accounting for about 72.53% of all the samples. The mantle length of males ranges from 94 mm to 406 mm with a higer concerntration in 240 mm to 320 mm which accounts for 70.26 percentage of the total samples. The body weight offemales ranged from 25 g to 3 900 g with a dominative weight range from 400 g to 1 200 g accounting for about 82.71% of the total sample. The body weight of males ranged from 33 to 2170g with a dominative weight range from 200 to 1 000 g accounting for about 87.82 of the total sample. The ration of the somatic body weight （SBW）to BW of females ranged from 31.69% to 80.51% with an average of 60.45%. That of males ranged from 37.05% to 81.35% with an average of 62.72%. The relationship between the ML to BW and ML to SBW differed with their genders by the analysis of covariance （ANCOVA） . The power functions is suitable for growth models for ML to BW for both sexes, however, power function and exponential function are suitable for describing the relationship between ML and SBW for females and males by the Akaike＇s information criterion （AIC） , respectively. The ration of males to females in April, May and June werel.87 ： 1, 1.61 ： 1, 1.17 ： 1 with an average of 1.61 ： 1 for all the samples. Different genders reach to different maturity level in different months. The maturity level increased as the time went by. The feeding stage differed fromgenders and different months and it seemed that the grade increased with the month increased.Different Renders have different foods in their stomaches at different time too.