东海带鱼主要体征与个体繁殖力的关系

Relationships between main physical characters and individual fecundities of hairtail Trichiurus japonicus in the East China Sea

利用2003年4～8月在东海长江口渔场和舟山渔场采集的带鱼(Trichiurushaumela)样品,对东海带鱼的个体繁殖力、以及个体繁殖力与各主要体征指标的关系进行分析。结果表明,个体绝对繁殖力r、相对繁殖力r/L和r/W均呈正态分布,分别为r～N(39233 4.5810×108)、r/L～N(150.33 2940.89)和r/W～N(140.95 284.26);个体绝对繁殖力r和相对繁殖力r/L与各度量体征指标呈幂函数关系,与称量指标则为线性相关关系;个体相对繁殖力r/W与各体征指标的关系均不十分密切;个体绝对繁殖力r与肝重的关系为:r=WLiv/(6.8531×10-6WLiv+2.4326×10-5);个体绝对繁殖力r与各体征指标的多元逐步回归方程为:r=-91304.2+225.1L+18070.1Lk+389.3Lh+801.0WLiv;个体相对繁殖力r/L与各体征指标的多元逐步回归方程为r/L=14.12057+1.021L+3.484WLiv,用肛长和肝重的变化可以反映个体相对繁殖力r/L的变动。

Using the individuals of hairtail Trichiurus japonicus Temminck et Schlegel collected in Changjiang Estuary and Zhoushan fishing ground in East China Sea from April to August 2003, the individual fecundities and the correlations between individual fecundities and main physical characters of hairtail were analyzed. The measured samples were at maturation stages IV and V in sex gland. Five measured indices are anal length (L ), head length (L _h), body height (L _d), body width (L_ k) and eye diameter (L_ e), and four weighed indices are body weight (W ), net weight (W _e), sex gland weight (W_ x) and liver weight (W _(Liv)). The results show that: (1) the individual absolute fecundity r , the individual relative fecundity r/L and r/W are all following normal distribution, namely r-N (392334.5810×10~8), r/L-N (150.332940.89) and r/W～N (140.95284.26), respectively; (2) r and r/L are of power function relation with measured indices and of linear function with weighed indices, while r/W is hardly of close relation with the main physical character measures; (3)the expression of the relation between r and W _(Liv) is r=W _(Liv)/(6.853 1×10^(-6) W _(Liv)+2.432 6×10^(-5)),and the multiple stepwise regression equation of r/L and the main physical character measures is r/L =14.120 57+1.021L+3.484W _(Liv); (4) the variations in L and W _(liv) can reflect the fluctuation in individual relative fecundity.