长江上游宜宾江段渔业资源现状研究

Present Status of Fishery Resources in Yinbin Section of the Upper Yangtze River

为了解长江上游宜宾江段鱼类群落结构和渔业捕捞现状及变化趋势，为物种和资源保护提供依据，该文对宜宾江段的流刺网和小钩等主要作业渔具的渔获物进行了调查，对渔获物种类组成、捕捞规格和单位捕捞努力量渔获量等进行了统计分析．结果表明：在宜宾江段共采集到鱼类49种，隶属于3目10科29属，以鲤形目和鲇形目鱼类为主．圆口铜鱼、瓦氏黄颡鱼、异鳔鳅鮀、宜昌鳅鮀和蛇鮈为该江段的优势种．采集到长江上游特有鱼类11种，占鱼类总种数的22.4％，其中一半以上的特有鱼类为偶见种．宜宾江段渔业捕捞规格普遍偏小，大部分捕捞个体体质量在100 g以下，体长在150 m m以下．该江段流刺网和小钩的单位捕捞努力量渔获量仅为每船1～2 kg／d ．宜宾江段渔业资源已严重衰退，许多特有鱼类变为偶见种，渔业捕捞渔获量偏低，捕捞规格偏小，建议采取休鱼等措施，促进物种和资源的保护．

The purpose of this study was to understand the present status and changing trend of the fish community structure and fishing in Yibin section of the upper Yangtze River ,and to provide information for species and resources conservation .Investigations of catch per unit effort ,catch composition and fish‐ing size of different fishing gears including drift‐trammel‐net and baited hook were carried out and the data collected were analyzed statistically .Altogether ,49 fish species ,belonging to 29 genera ,10 families and 3 orders ,were collected in this section of the Yangtze River .Most of them belonged to Cypriniformes and Siluriformes .Coreius guichenoti , Pseudobagrus v achelli , Gobiobotia boulengeri , Gobiobotia filifer and Saurogobio dabryi dominated the fish community .Eleven endemic fish species were recorded ,accounting for 22.4% of the total ,and more than half of them were rare species .The fishing size in Yinbin section was small in general ,and most of the individuals caught were smaller than 100 g in weight and 150 mm in length .The catch was low ,and the catch per unit effort of drift‐trammel‐net and baited hook was only 1-2 kg per boat per day .In conclusion ,the fishery resources in Yibin section of the upper Yangtze River have been declining seriously with low catch and small fishing size ,and lots of endemic species have become rare .Measures such as fishing closures are suggested to be taken to improve the species and resources con‐servation .