珠江口崖门鲈鱼年龄和生长的研究

AGE AND GROWTH OF THE JAPANESE SEE BASS (LATEOLABRAX JAPONICUS) IN YAMEN OUTFALL OF PEARL RIVER ESTUARY

本文依据1983年6月至1986年1月对290尾鲈鱼年龄和生长的调查资料,阐明鲈鱼鳞片年轮特征并计算出鲈鱼体长与鳞长、体长与体重的关系式。研究表明:3龄以前属幼鱼阶段,体长和体重的相对增长率较大,生长指标较高,3龄以后进入成鱼生长阶段。其生长适合von Bertalanffy生长方程,体重生长曲线的拐点位于3.05龄。因此以3龄、体重3.5公斤左右的鲈鱼作为商品鱼加以捕捞,经济效益最高。

The 290 specimens of young and adult Japanese sea bass (Lateolabrax japonicus) were collected from Yamen Outfal of Pearl River Estuary, during the period from June 1983 to January 1986. Scales used to determine the the age and growth rates of the fish are taken from the middle part between the dorsal spines and the lateral line. The annual ring is characterized by the rank of dense and sparse of the rings on the scale. New annual ring began 1o appear mostly during February-March, The Japanese sea bass matures at 3 years old and the growth rates decreased after the adult stages. The body length L (mm) as function of the scale radius R (mm) is expressed as L= 104.1999R-3.6554 and the length L(mm)- weight W(g) relationship is W = 5.0765 ×10-5 L2.8101. Growth of the Japanese see bass fits in von Bertalanffy equationship well. The growth parameters are: L. = 972.32mm, W∞= 12635.66g, K = 0.3146,to =-0.4401 and the turning point of growth curve in weight tr = 3.05 years. Due to the fact that the growth rate in weight increases with the increasing ages until 3 years old, the minimum catchable age and size of this fish may be suggested to be 3 years old with 600mm in length and 3.5kg in weight.