黑龙江抚远江段冬季江鳕的摄食生态研究

Research on feeding ecology of Lota lota in winter in the Fuyuan reach of Amur River

本研究采用胃含物分析法,对2019年1月抚远定置刺网捕获的319尾江鳕(Lota lota)胃含物样品进行分析,捕获江鳕样本体长范围为162~536 mm,研究江鳕的食物组成及其随体长和性别变化特征。研究结果显示:抚远江段江鳕主要以鱼类、甲壳类和水生昆虫为食,属于肉食性鱼类;基于相对重要性指数(IRI)分析,甲壳类是江鳕最重要的食物类群(IRI=8 301.79),其次是鱼类(IRI=7 059.39),水生昆虫最低(IRI=3.56)。江鳕的食物组成未随着体长的增加出现明显的食性转换,但在食物的质量百分比上出现了明显的变化,鱼类的质量百分比逐渐增加,甲壳类逐渐减少。江鳕不同体长组的空胃率差异不显著,平均饱满指数呈现显著性差异;不同性别的空胃率差异不显著,平均饱满指数差异显著。

From the perspective of economics and conservation,Lota lota has delicious meat,high nutritional value and fast growth,so it has a certain economic value.At the same time,in recent years,the resource quantity of L.lota has continued to decline,and it has been listed as a national second-class protected fish.The effective utilization and protection of L.lota resources are urgent.Based on the protection and development of L.lota resources,this paper studies the feeding habits of L.lota and analyzes the stomach contents of 319 L.lota samples captured by fixed gillnet in Fuyuan in January 2019 by using the traditional analysis method.The body length of the captured L.lota samples ranges from 162 mm to 536 mm.The main purpose of this study was to study the food composition of L.lota and its variation characteristics with body length and sex.The research results showed that L.lota mainly fed on fish,crustaceans and aquatic insects,and they were carnivorous fish.The food composition of L.lota does not significantly change with the increase in body length,but the food mass percentage changes significantly.The mass percentage of fish gradually increased,while the crustaceans gradually decreased.With the increase of L.lota body length,the bait type and quality percentage variation was consistent with the“optimal feeding theory”.The feeding habits of L.lota in Fuyuan reach of Amur River were studied for the first time,providing certain basic data for the artificial propagation and breeding of L.lota to provide a scientific basis and theoretical basis for rational utilization and protection of L.lota resources.