南沙群岛西南陆架区底拖网主要经济渔获种类组成和数量变动

根据1993-2002年南海区3省市渔业公司在南沙群岛西南陆架区底拖网的生产资料和渔业资源调查资料，分析了底拖网主要渔获种类组成和数量变动。结果表明，底拖网渔获种类组成基本相同，主要渔获经济种类有20多种，以蛇鲻属（Synodidae）、大眼鲷属（Priacanthidae）等底层鱼类为主，占总渔获物的70．9％。经济鱼类资源渔获率有明显的年间变动。底层鱼类资源除蛇鲻属和大眼鲷属外，其他种类如石斑鱼属（Serranidae）、鲱鲤属（Mullidae）、红笛鲷（L．sanguineus）、黄鳍马面纯（T．xanthopterus）、刺鲳（Psenopsis anomala）等波动很大，而中上层鱼类资源和头足类资源则相对稳定。分析认为捕捞是引起经济鱼类资源数量变动的主要原因。

Species composition and quantity dynamics of main economical fishes from bottom trawl in southwestern continental shelf of Nansha Islands

Based on the data collected by fishing records and field survey of state-owned fishing companies in the South China Sea during 1993-2002,the authors analyzed species composition and quantity dynamics of main commercial fishes from bottom trawl in southwestern continental shelf of Nansha Islands.The results showed that during the ten years,more than 20 species were the main catches from bottom trawl and the species composition were similar each year.The demersal species such as Synodidae,Priacanthide, Serranidae, Nemipteridae,Mullidae and L.sanguineu were predominant and account for 70.9% of the total catches in average.The catch rates of main economical fishery resource except Synodidae and Priacanthid,and others such as Serranidae,Mullidae,L.sanguineu,Thamnaconus xanthoperus and Psenopsis anomala had distinct annual variation in number.While pelagic fisheries and Cephalopoda were relatively stable,it's suggested that fishing should be the main cause of the economical fishes variation.