中国南海北部剑尖枪乌贼资源现状及其合理利用对策

头足类动物是海洋渔业资源的重要组成部分.剑尖枪乌贼(Loligo edulis)是头足类动物中主要种类之一,其在中国南海的资源分布和变动等规律还不清楚.因此,调查南海北部剑尖枪乌贼的资源现状,探索其时间变动规律,对于更好地开发利用南海剑尖枪乌贼资源具有积极意义.本文基于2000-2002年调查数据,介绍中国南海北部剑尖枪乌贼生物学特性,分析其资源密度指数的区域、昼夜、季节以及水深变化规律.结果表明,海南岛以东近海剑尖枪乌贼的平均密度指数和平均尾数密度指数均明显高于北部湾及海南岛南部近海;整个南海北部剑尖枪乌贼的平均密度指数和平均尾数密度指数夜晚高于白天,其中平均密度指数以海南岛以东最高,为6.453 kg/h;平均尾数密度指数以北部湾及海南岛南部为最高,为134.6 ind/h;整个南海北部剑尖枪乌贼的最高网次密度指数和最高网次尾数密度指数均出现于夏季,最大值均出现在海南岛以东;随着水深变化,密度指数和尾数密度指数最大值出现在北部湾及海南岛南部18～20 m水深范围,其值分别为15.500 kg/h和910.0 ind/h;其次出现在海南岛以东100～110m水深范围.南海北部剑尖枪乌贼渔获量在头足类中超出中国枪乌贼(Loligo chinensis)居于首位,其资源还有一定的开发潜力.本研究旨在为剑尖枪乌贼资源的保护利用提供科学依据,为中国南海海洋生态系统可持续发展提供理论基础.

Resources status and conservation strategy of Loligo edulis Hoyle in the northern South China Sea

he fishery production has been decreased with over-exploitation of marine fisheries resources. Cephalopoda is an important part of marine resources. The resources status of cephalopoda has been under consideration. is the major species among cephalopoda animals. Little information on resources status and variation trends of was reported. Based on the fishery resource survey in the north of South China Sea during 20002002, the present paper analyzed density index for the circadian, seasonal, and regional variation and the biological characteristics of Loligo eduli from the east of Hainan Island was significantly higher than that of from Beibu Gulf and south of Hainan Island. Density index and individual density index of in the north of South China Sea during the night were higher than those of during the day time. The highest density index (6.453 kg/h) of was observed in the east of Hainan Island. The highest individual density index (134.6 ind/h) was observed in the south of Hainan Island. The findings of seasonal variation of indicated that the density index and individual density index in summer were higher than those of other seasons. The highest index was observed during the summer in the east of Hainan Island. The density index (15.500 kg/h) and individual density index (910.0 ind/h) of in the depth of ranging from 18 m to 20 m in Beibu Gulf and the south of Hainan Island were higher than those of ranging from 100 m to 110 m in the east of Hainan Island. The catches of was the predominant in yield among the catch species, which was higher than that of among the Cephalopoda species from the northern South China Sea. In order to prevent from overfishing of fishery resources, strategies of protection and utilization for should be carried out, which make the sustainable development of fishery resourses.