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棘头梅童鱼是长江口水域的常见小型经济鱼类,具有一定的捕捞价值.为了解长江口棘头梅童鱼食物组成和摄食习性的季节变化,本研究利用胃含物分析法对2013年11月—2014年8月在长江口水域捕获的棘头梅童鱼样本进行了分析.结果表明:长江口棘头梅童鱼全年摄食的饵料生物有8目30种,其中虾类(游泳亚目)是主要饵料生物,相对重要性指数百分比(IRI%)为38.5,优势指数(Ip)为79.1;其次为糠虾目和磷虾目.全年饵料生物中的主要优势种类为葛氏长臂虾、安氏白虾、脊尾白虾、长额刺糠虾、短额刺糠虾、光背节鞭水虱和中华哲水蚤等.饵料生物优势种存在季节差异,春季和夏季的主要优势种均为葛氏长臂虾、安氏白虾和短额刺糠虾,秋季主要优势种为长额刺糠虾、短额刺糠虾和脊尾白虾,冬季主要优势种为葛氏长臂虾、中华哲水蚤和中华假磷虾.长江口棘头梅童鱼全年空胃率为10.4%,冬季最高,秋季最低;全年平均胃饱满系数为0.6%,冬季最低,春季最高,摄食习性存在季节变化.
In order to understand the seasonal changes of food composition and feeding habits of the fish in the head of the Yangtze River Estuary, this study used the method of gastric contents analysis to analyze the 2013 From November to August 2014, the samples of Acanthopagrus chinensis captured in the Changjiang Estuary waters were analyzed.The results showed that there were 8 species and 30 species of edible fish fed on the Yangtze River estuary all year round, among which shrimp ( (Subunit) was the main bait organism with the relative importance index (IRI%) of 38.5 and the dominant index (Ip) of 79.1, followed by the order of the shrimp and krill.The main dominant species in the feed organisms were Ge Chinese white shrimp, white shrimp, long-legged shrimp, short-legged shrimp, Halophila aquatic larvae, and Chinese cabbage daphnids, etc. There are seasonal differences in the dominant species of bait in spring and summer The main dominant species are Gracilaria lemaneiformis, Pseudostellaria barbata and Pinctada martensii, the main dominant species in autumn are long-legged shrimp, short-legged shrimp, and spiny white shrimp. The main dominant species in winter are Ge Long-arm shrimp, Chinese phlogistic daphnia and Chinese fake krill. Which was the highest in winter and the lowest in autumn. The average annual coefficient of gastric fullness was 0.6%, the lowest in winter and the highest in spring. There was a seasonal change in feeding habit.