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本文根据1982年4月至1984年4月所采集的3964尾湖鲚样本,进行生长与死亡、不同体长的摄食习性的研究。研究表明,湖鲚的自然死亡系数M为0.52,捕捞死亡系数F为2.66,总死亡系数Z为3.18,生长的拐点年龄为2.548。体长达131mm时,饵料中开始出现经济鱼虾;体长达170mm时,饵料中的经济鱼虾比重急剧上升,出现率为50—100％,经济鱼虾饱和分指数占饱和总指数85—99％,其中白虾约占40％—94％。 本文应用Schaofer模式、Beverton-Holt模式计算得出:湖鲚开捕年龄为0.5龄时太湖最大持续渔获量为652.5万公斤,最适捕捞努力量为3190000(日,吨位)。综合分析认为合理利用湖鲚资源的最佳开捕年龄应为1.5龄,即使F不变,渔获量也将上升三倍。
In this paper, from April 1982 to April 1984 collected 3964 taihuo samples, growth and death, feeding habits of different body length. The results showed that the natural death rate M of Lake 鲚 was 0.52, the fishing mortality F was 2.66, the total mortality Z was 3.18, and the inflection age of growth was 2.548. Body length of 131mm, the food began to appear economic fish; body length of 170mm, the proportion of economic fish and shrimp in food increased sharply, the rate was 50-100%, the saturated index of economic fish accounted for the total saturation index 85- 99%, of which white shrimp accounts for about 40% -94%. Using Schaofer model and Beverton-Holt model, the maximum sustained catch of Lake Taihu was 0.5255 million kg and the optimal fishing effort was 3190000 (day and tonnage). According to the comprehensive analysis, the optimum age for catching larval resources should be 1.5 years. Even if F is the same, catches will increase by three times.