黄渤海区三重刺网渔业结构分析

Analysis of fishery structure of trammel net in the coastal regions along the Yellow Sea and the Bohai Sea

为确定三重刺网适用范围,促进《全国海洋捕捞渔具目录》的实施,于2015年在黄渤海区以三重刺网渔业为研究对象,调查了刺网渔船渔业动态和三重刺网渔具种类和作业参数,并追踪调查了代表性渔具的渔获结构、产量和产值,对三重刺网作业渔船的捕捞能力与经济效益加以分析。结果表明,三重刺网渔具对甲壳类和鲆鲽类的选择性较强,捕捞效果好,兼捕幼鱼比例相对较低,是目前近海捕捞渔具中选择性比拖网和张网相对较好的作业渔具。但鉴于目前生产中使用的三重刺网内网衣网线较细,缠绕力强,兼捕现象较为严重,在经济鱼类幼鱼较多的渔场作业,会对渔业资源造成较大的损害。同时从渔民收入角度出发,三重刺网过渡期以后的归属管理应开展进一步调查和研究。

The trammel net is used widely for fishing in coastal waters.As a controversial fishing gear,it has attracted attention for the conservation of fishery resources,and ranged as a kind of temporal marine fishing gear in the transitional period.To determine its admittance or prohibition of use and promote the implementation of National Marine Fishing Gear Catalog,the trammel net fishery was investigated in the area of the Yellow Sea and the Bohai Sea in 2015.Based on the investigation of gillnetters fishing state and kinds of trammel net,catch composition,fishing capacity and economic benefits of trammel net were analyzed.Results showed that there were mainly 4 kinds of trammel net in the coastal regions of the Yellow Sea and the Bohai Sea,their target species were Oratosguilla Oratoria,Fenneropenaeus chinensis,Portunus trituberculatus and Cleisthenes herzensteini respectively.There were more than 50% crustanceans in the captures of squilla or prawn trammel net,and more than 70% Portunus trituberculatus in crab trammel net.By-catches of trammel net consisted mainly of demersal fish,such as Cynoglossus joyneri,Paralichthys olivaceus,Platycephalus indicus,Lateolabrax maculatus etc.It was revealed that trammel net had advantages of the highly selective ability and fine fishing effects for crustanceans and flatfishes compared to single gillnet.Trammel net was currently a better fishing gear than trawl net and filter net showed relatively lower ratio of by-catched juveniles,but the string of the inner net of trammel net was fine and had strong entanglement,it would cause great damage to fishery resources if there were many juveniles of economic fishes in the fishing grounds,especially for squilla and prawn trammel net with the inner mesh sizes of 50 mm to 60 mm.Many registered gillnetters fishes periodically with trammel net,whose yield accounts for 90% of the gillnet fishery,thus the fishery of trammel net is an important source of livelihood and income for fishermen.Further investigation and research should be done to confirm the management of trammel net after the transitional period.