北部湾多鳞鱚生长与死亡参数的估算

Estimation of Growth and Mortality Parameters of the Silver Sillago(Sillago sihama) in Beibu Gulf

利用2008年3-9月北部湾底拖网和刺网渔获物中采集的样本,对北部湾多鳞鱚的生长、死亡特性进行了初步研究,并利用单位补充量产量模型对多鳞鱚渔业的开发状态进行了评估。结果表明:北部湾多鳞鱚优势体长为100～130mm,占60.71%;优势体重为5～25g,占83.96%;雌性个体略大于雄性个体,性比为1:1.36,雌雄个体数量不平衡;von Bertalanffy生长方程的参数分别为:L∞=188.6mm,K=0.51,t0=-0.32;体重的生长拐点年龄为1.86龄;总死亡系数、自然死亡系数和捕捞死亡系数分别为2.58、1.217和1.36;渔业生物学参考点F0.1和Fmax的值分别为0.34和0.50,渔业资源已处于过度利用状态。

The growth and mortality of the silver sillago （Sillago sihama） has been primarily studied according to the commercial catch sample caught in bottom trawls and gill nets in Beibu Gulf from March to September 2008, and the status of the silver sillago has been evaluated using the yield per recruitment model. The result shows that the dominant length of Sillago sihama ranges from 100 mm to 130 mm, accounting for 60.71 percent of the total; the dominant weight is between 5 g and 25 g, accounting for 83.96 percent of the total. The mean length of the female Sillaga sihama is larger than that of the male. The female is less than the male in population, by the sex rate of 1：136. The estimated parameters for yon Bertalanffy growth function of the stock are L∞=188.6 mm, K=0.51 and t0=-0.32 respectively. The turning point in body weight growth curve of the stock is situated at the age of 1.86. The instantaneous rates of total mortality, natural mortality and fishing mortality are respectively 2.58, 1.217 and 1.36. The fishery biological reference points F0.1 and Fmax are 0.34 and 0.50, re-spectively. The silver sillago fishery has been overfished.