东海北部和黄海南部鲐鱼年龄和生长的研究

本研究采用2002年11月～2003年8月在东海北部和黄海南部海域(30°～34°N、126°E以西)所获取的鲐鱼渔获样品,合计采集777ind,通过对鲐鱼耳石生长轮的观察和基础生物学测定,研究了鲐鱼的年龄和生长。结果表明叉长与体重的关系雌雄间没有显著性差异;所鉴定鲐鱼年龄组成为1～3龄鱼,共3个年龄序列,并补充20世纪80年代4～5龄鱼对鲐鱼的生长规律进行研究,采用Walford方法拟合,其生长参数K、L∞、t0分别为0.31993、451.3514和-1.20307;鲐鱼的生长拐点年龄为2.7yr,拐点体重为450g,拐点叉长为320mm。比较分析东海群系鲐鱼的渔业生物学历史状况,在目前所能观察得到的鲐鱼年龄段内(1～3龄),东海区鲐鱼个体平均叉长比20世纪80年代的都要小;与闽南、粤东近海地方群系的相比,东海群系的平均叉长在鲐鱼的整个生长阶段都明显的大。

Age and Growth of Pneumatophorus japonicus in the North of the East China Sea and the South of the Yellow Sea

Based on the data from bottom trawl surveys from November 2002 to August 2003 in the north part of the East China Sea and the south part of the Yellow Sea, the age and growth of Pneumatophorus japonicus were studied. By observing the otoliths and measuring their biological characters, the results showed that there was no visible difference between male and female in the relation between fork length and weight. The ages included three groups, age 1 to age 3. In order to study its growth regulation, the data of age 4 to age 5 from the 1980's were added. The parameters of growth equation obtained from Walford's method showed that K, L_∞, t_0 were 0.31993, 451.3514 and -1.20307, respectively. The turning points of age, weight and length were age 2.7, 450 g and 320 mm respectively. Comparing biological characters of Pneumatophorus japonicus in the East China Sea, the present mean length becomes less than that of the 1980's from age 1 to age 3, and the mean length of the East China Sea is larger than that of the offshore areas of Minnan and Guangdong Province.