云龙湖水库青梢鲌的生长特性

采用鳞片和耳石对取自云龙湖水库的青梢鲌(Erythroculter dabryi)进行了年龄鉴定,并对其生长特性进行分析。结果显示:以鳞片和耳石为年龄鉴定材料时,二者的吻合率分别为59.57%和90.16%。年龄鉴定结果显示,所捕获的青梢鲌由1~8龄个体组成,主要是3~5龄个体;个体体长与耳石半径之间呈直线相关:L=9.5632R-0.1595(R2=0.995,n=175),体重与体长呈指数函数相关:W=1.07×10-2L3.3035,其生长规律符合von Bertalanffy方程:Lt=20.4741(1-e-0.2531(t+0.8056)),Wt=229.5864(1-e-0.2531(t+0.8056))3.3035;青梢鲌生长拐点年龄为3.92龄,对应的体长为14.28 cm,体重为69.88 g;3.92龄为合理的捕捞时期。

Growth Characteristic of Erythroculter dabryi in Yunlonghu Reservoir

263 Erythroculter dabryi were collected in Yonglonghu Reservoir,South of Xuzhou city,Jiangsu Province,from October 2004 to April 2005.Growth characteristic of E.dabryi in Yunlonghu Reservoir was analyzed by the scale and otolith.Ages assigned to scales and otoliths agreed 59.57% and 90.16% for samples in Yunlonghu Reservoir respectively.Otolith is better than scale to use for estimating age of E.dabryi,it has high precision and good reproducibility.The catch of E.dabryi contained 8 age classes ranging from 1 to 8 with 3~5 years old as preponderant age classes.The body length(L)and the otolith radius(R)were linearly correlated and expressed as L=9.5632R-0.1595(R2=0.995,n=175).The body length and the weight were exponentially correlated.Growth of E.dabryi can be described with von Bertalanffy equation expressed as Lt = 20.4741(1-e-0.2531(t 0.8056)),Wt =229.5864(1-e-0.2531(t 0.8056)) 3.3035.The body weight growth inflexion point is 3.92 a,with the corresponding body length of 14.28 cm and body weight of 69.88 g.