千岛湖大眼华鳊年龄、生长和繁殖的初步研究

Primary study on the age，growth and reproduction of Sinibrama macrops in Qiandao Lake

摘要:

为了解千岛湖大眼华鳊（Sinibrama macrops）的种群状况，于2008年7月- 2009年4月在千岛湖采集了707尾实验样本，以其鳞片为材料进行年龄鉴定，对大眼华鳊种群的年龄、生长和繁殖特征进行了研究。结果表明：所获得的大眼华鳊样本年龄由雌性0⁺~5⁺（1~6龄）6个年龄组和雄性0⁺~4⁺（1~5龄）5个年龄组组成，雌雄的优势年龄组均为1⁺~2⁺龄（2~3龄），占总数的71.4%；体长范围为9.2~20.4 cm，体重范围为18~195 g；体长和体重生长关系式为W=0.0248L^2.8985（r=0.9482）；拟合的Von Bertalanffy方程为：L_t=24.04［1-e^{-0.1477(t+2.8540)}］，W_t=249.38［1-e^{-0.1477(t+2.8540)}]^2.8985；生长拐点年龄为4.35龄时，拐点体长、体重为15.74 cm、73.13 g；雌、雄性比为1.27∶1，绝对繁殖力为1 870～18 665粒，平均6 279粒，个体体长相对繁殖力平均为（408±214.22） 粒/cm，范围为134～989粒；个体体重相对繁殖力平均为（98±40.49） 粒/g，范围为38～215粒。调查期间，雌、雄鱼性腺成熟系数9月达到峰值，分别为22.85%、12.56%，表明9月也可能存在一个繁殖高峰。其1～4龄个体体长年增长量、瞬时生长率、生长常数、生长指标随年龄生长而下降，对应其个体体重年增长量、瞬时增长率、生长常数生长指标随年龄增长逐渐上升，丰满度在3月达到峰值。根据拐点体长、体重可知，目前存在过度捕捞的状况，应限制4龄以下个体的捕捞，有利于该物种自然资源的保护。

Abstract:

To evaluate the current status of 〖WTBX〗Sinibrama macrops〖WTBZ〗 population in Qiandao Lake, age、 growth and reproduction characters were studied using 707 specimens collected from July 2008 to April 2009. Ages were determined by reading annuli on scales, The estimated age ranges were between 0⁺-5⁺years for females and 0⁺-4⁺years for males, the age group advantage is 1⁺-2⁺, which accounts 74.1%. The body length and body weight range of population is 9.2 cm-20.4 cm, 18-195 g. The growth trait of the length and weight was similar as W=0.0248L^2.8985（r=0.9482）, The body growth pattern can be well described by von Bertalanffy equation and they were L_t=24.04［1-e^{-0.1477(t+2.8540)}］，W_t=249.38［1-e^{-0.1477(t+2.8540)}]^2.8985, The growth age at inflection point was 4.35 year old and the corresponding body length and body weight were 15.74 cm，73.13 g. The sex ratio for female and male is 1.27∶1, The individual absolute fecundity varied from 1 870-18 665 eggs(average 6 279), and the individual relative fecundity(FL) varied from 38-215 eggs/g (average 98), The gonadosomatic index for female and male is 22.85%,12.56%, and the female fish are total spawners. Growth indexs in general declined with age growth, and the condition factor reached in its peak in March. According to the body length and body weight in inflexion there had overfished condition, therefore, the countermeasures should be taken such as restricting the individual which is below 4 age, in order to protect the resources of Sinibrama macrops.