淀山湖光泽黄颡鱼的生物学初步研究

光泽黄颡鱼(Pelteobagrusnitidus)是淀山湖重要的优势种之一,也是渔民重要的捕捞对象。2011年8月至2012年7月在淀山湖采集780尾光泽黄颡鱼样本,按肉眼观察选取体态完整的238尾进行体长分布、体重分布、体长与体重的关系、性比、食性、性腺成熟度和性腺指数等方面的生物学初步研究。研究结果表明:(1)光泽黄颡鱼体长范围为4.7~16.0 cm,优势组为8.0~12.0 cm;体重范围为1.3~28.4 g,优势组为5.0~15.0 g;(2)雌、雄样本平均体长分别为10.9cm和11.4 cm,平均体重分别为15.1 g和15.9 g;(3)雌雄样本体长与体重关系为,W♀=0.041×L2.533,W♂=0.037×L2.557,呈显著差异;(4)雌性光泽黄颡鱼最小性成熟个体体长为8.6 cm,体重为6.9 g;雄性最小性成熟个体体长为9.4 cm,体重为8.9 g;(5)雌、雄性腺指数具有差异性,雌性性腺指数大于雄性,成熟个体的性腺指数大于未成熟个体,雌性性未成熟个体性腺指数随着鱼体增大而增大,而雌性性成熟个体的性腺指数却随着鱼体增大而减小;(6)胃含物以虾为主,摄食等级以2~3级为主,占57.66%。

Primary biological study of yellow catfish(Pelteobagrus nitidus)in Dianshan Lake

Yellow catfish （PeIteobagrus nitidus）is an important target species in Dianshan Lake fishery. From August 2011 to July 2012, 780 specimens of Pelteobagrus nitidus were sampled to study their biology . The results showed that： （ 1 ） The length distribution of yellow catfish samples was 4.7 - 16. 0 cm, with a dominant group of 8.0 - 12.0 cm; The weight distribution of those samples was 1. 3 - 28.4 g, with a dominant group of 5.0 -15.0 g. （2） The mean length of females and males were 10.93 cm and 11.37 cm, with a mean weight of 15.1 g and 15.88 g, respectively. （3）The length-weight relationships of females and males were described as W♀ = 0. 041 x L2533 , and W♂ = 0. 037 ×L2.557 , respectively, and with significant ditterenee based on covarianee analysis. （4） The length of minimum sexual maturity of female and male yellow catfish were 8.6 cm and 9.4 em respectively. （5） The mature individuals＇ gonad somatie index （GSI） of yellow catfish was obviously higher than the immature individuals＇ and the female immature individuals＇ GSI, which tended to increase with total length and conversely for the female mature individuals＇. （6） The main prey of yellow catfish was shrimp and the feeding intensity was high in the classes 2 and 3 which accounted for 57.66% of the total specimens.