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出 处:《大连水产学院学报》2007年第5期392-396,共5页Journal of Dalian Fisheries University
基 金:浙江科技厅计划项目(2003C32033)
摘 要:根据近几年东海区渔业资源调查并结合相关历史资料,对东海区大黄鱼Pseudosciaena crocea的渔业状况、种群结构、生殖特性及种群洄游分布规律等进行了研究。结果表明:自20世纪70年代以后,由于东海区大黄鱼渔业投入的捕捞力量和强度过大,已远远超过了大黄鱼资源的承受能力,大黄鱼资源量快速衰减,过度捕捞使东海区在20世纪80年代中期已形不成大黄鱼渔汛,渔业部门虽然制订了许多资源保护措施,但至今大黄鱼仍属东海区资源严重衰退的鱼种;大黄鱼群体组成呈现低龄化、小型化趋势,群体优势年龄组和优势体长组分别由20世纪70年代的4~7龄(220~350 mm),减小到90年代以后的1龄(140~160 mm),且初次生殖年龄提前。The population structure, reproduction characteristics and the regular migration pattern were investigated in large yellow croaker Pseudosciaena crocea by a survey and collected data of the fishery resources in Zhejiang coast and the East China sea in recent years. The results showed that overfishing due to great capture capacity and intension led to the stock decline since 1970's. Since mid - 1980's there was no fishing season of the large yellow croaker in the main fishing ground because of the excess capture, although fishery department had carried out many measures to protect the stock. The large yellow croaker still are listed in the species whose stock was declined seriously in the East China sea. The population structure of the fish population presents lower age, early maturation and miniaturization in size, the predominance population with 1 age and 140 - 160 mm in body length after 1990's compared with 4 -7 age and 220 -350 mm in the 1970's.
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