江苏沿岸定置张网主要渔获组成以及对经济鱼类幼体的损害分析

深水张网是吕四渔场传统的作业方式,渔获量占江苏省海洋捕捞总量的比重较大。根据2004年4月~2005年11月吕四渔场深水张网渔业监测资料,结合渔业统计数据,分析了该渔业渔获物种类组成及其季节变化,以及主要经济鱼类渔获物种类组成和幼鱼比例。结果表明,各季节深水张网优势渔获物种类组成具有明显的季节变化特征,春季主要以小黄鱼、黄鲫、焦氏舌鳎和葛氏长臂虾为主,夏季为小黄鱼、黄鲫、焦氏舌鳎和银鲳,秋季为小黄鱼、焦氏舌鳎、棘头梅童鱼、灰鲳和银鲳,冬季为小黄鱼、焦氏舌鳎、棘头梅童鱼和斑鰶;小黄鱼和焦氏舌鳎是深水张网渔业常年优势渔获物。主要经济鱼类小黄鱼以6月份平均网产最高,但主要以幼鱼为主,2004年和2005年的平均体重分别仅0.81 g/ind和1.04 g/ind,幼鱼渔获尾数分别占到99.1%和99.8%,累计损害幼鱼尾数分别达1.84×107ind和2.37×107ind;银鲳平均体重3.22 g/ind和3.8 g/ind,累计损害幼鱼尾数分别为4.84×105ind和4.41×105ind。建议对深水张网渔业加强管理,可对该渔业提前一个月休渔,提高网囊网目尺寸,并强化管理力度。

Analysis on the species composition of catches together with the injured status of commercial juvenile fishes caught by stow net with double stake along the coastal waters of Jiangsu Province

The fishing of stow net with double stake is one of the traditional operations along the coastal waters of Jiangsu province,its catches have been occupied more propotion in total marine catches of Jiangsu province.Based on the independent fisheries data related to stow net with double stake conducted in the water areas mentioned above during April 2004 to November 2005.The present paper represents on the species composition of the catches and the injured status of commercial juvenile fishes as well.According to the analyzing on the species composition and monthly variation of the catches,as well as the injured juvenile numbers of commercial fishes,it came to the conclusion that the composition of dominant species in catches obviousily varied in various season.There were dominated by Larimichthys polyactis,Setipinna taty,Cynoglossus joyneri and Palaemon gravieri in spring,by L.polyactis,Setipinna taty,C.joyneri and Pampus argenteus in summer,by L.polyactis,C.joyneri,Collichthys lucidus,Pampus cinereus and P.argenteus in autumn,by L.polyactis,C.jouneri,C.lucidus and Konosirus punctatus in winter.The CPUE of the most commercial species L.polyactis reached the peak in June,but most of them were the juveniles during 2004 and 2005,the average body weight were 0.81 g and 1.04 g respectively,the juvenile numbers accounted for 99.1% and 99.8% about,and the accumulative total number of the injured juveniles were respectively 1.84×107 ind and 2.37×107 ind about.At the same period,Pampus argenteus was dominated by juveniles too,the average body weight of them were 3.22 g and 3.8 g,the accumulative total number of injured juveniles were respectively about 4.84×105 ind and 4.41×105 ind.It was indicated that there were heavily negatively effected on the regional fishery resources by the fishing activities of stow net with double stake,although it could be brought great commercial benefit.Relevant management and conservation should be reinforced.It is herewith suggested that the closured fishing period should be moved up one month and the mesh size of cod end should be expended,and enhanced the management for this traditional fishing gear.