东海6种石首鱼的年龄鉴定与生长特性的研究

AGE AND GROWTH OF SIX SCIAENID FISHES (SCIAENDAE) IN THE EAST CHINA SEA

利用1985年9月-1988年10月长江口近海采集到的6种石首鱼的标本，以及1981年和1982东海作业区收集到的部分石首鱼标本，用且石切片机，对6种石首鱼的耳石进行切片试验，以确定6种石首鱼且石的最佳切片方法;并进行年龄鉴定。运用幂函数方程、vonBertalanffy生长方程和季节生长方程对6种石首鱼的生长特性进行分析和比较。结果表明，体长和体重的相关参数在不同种之间差异性显著，生长速度与极限体长（L∞）和极限体重（W∞）成正相关，生长速度的时间分布由K值决定。季节生长的冬滞点（WP）和耳石暗带的形成时间是一致的。

To compare the growth characteristics of sciaenid fishes, 7688 individuals of 6 sciaenid fishes were collected. 6619 of them were caught in Aug. 1985 to Oct.1988 with trawl in the Changjiang Estuary and adjacent waters. The others were in 1981 to 1982 caught with trawl by commercial fishing boat in the East China Sea. The big and thick otoliths of different sciaenid fishes were different in shape and stru-cture. Through cutting experiment with otolith slicer, the optimum location and di-rection of cutting was determined. The results of linear regression analysis based on an exponential equation showed that body length of these 6 sciaenid fishes had close relationship to their body weight, but the A and B for these species were remarka-ble different. The value of A of females was larger than that of males of the same species and had positive relationship with L∞ and W∞; but was the contrary with the value of B. By means of Walford's graphical method and method of least squares and ba-sing on von Bertalanffy growth equation, the growth parameters, K, L∞, W∞ and To, of the six sciaenid fishes were calculated. The result showed that the value ofK was negatively correlated to L∞. The species with larger L∞ and less K had la-rger growth rate and longer period of growth.With seasonal growth model: the seasonal gro- wth patterns of the six species were also simulated. lt indicated that the body gro-wth in winter and spring was much slower than that in summer and autumn. WP(winter point) of each species appeared in different time but appeared simultaneou-sly with the opaque zone of their own otoliths respectively.