应用资源密度面积法估算东海区头足类资源量

Application of resources density/area method to estimate Cephalopod stock of the East China Sea

根据2001年、2002年东海区渔业资源监测网海区站监测调查资料,采用资源密度面积法,对东海区大陆架海域头足类及其主要种类的资源量进行估算。结果显示:(1)东海区头足类资源密度2001年、2002年都以夏季为最高,分别为463.70 kg/km2和237.43 kg/km2;2001年春季和2002年冬季最低,分别为98.24kg/km2和125.43 kg/km2。(2)两年中太平洋褶柔鱼的年平均资源密度在所有头足类种类中都为最高,分别为145.07 kg/km2和101.85 kg/km2;而蛸类的资源密度为最低,分别为4.69 kg/km2和2.53 kg/km2。(3)2001年、2002年东海区大陆架海域的头足类资源量分别为375384.90 t和172692.90 t,以年平均资源量算出的MSY分别为238 553.56 t和144277.31 t。

Cephalopod is the important constitution of Mollusca, distributed in the Pacific, Atlantic and sea area along the South Pole, the total ouput is about 3.5 million tons every year on the world since 2000. In China, It is mainly distributed in the East China Sea, its output is occupied about 70% - 80% of the total of China. Sepiella rnaindroni historically was the main economic species in the East China Sea, but its resources has been seriously declined since 1980 owing to over-fishing, the average annual output was about 11 × 10^4 t during 1993 -2002, but the resources of others such as Sepia esculenta and Todarodes pacificus are relatively steading up to now. In recent a few years, along with the declining of the resources of demersal and bathydemersal fishes in the sea area mentioned above, due to with some peculiarity as with shorter life-cycle and rapidly growing etc, Cephalopod is getting more and more important position in the fishery. Present paper deals with the estimation on the biomass of Cephalopod together with their main species at continuental shelf area of the East China Sea by means of stock density/area method according to the data based survey of monitoring station within fishery resources monitoring network in the East China Sea during 2001 and 2002. It came to the conclusions given as follows： （ 1 ） The maximum stock density of Cephalopod was in summer both in 2001 and 2002, 463.7 kg/km^2 and 237.43 kg/km^2 respectively; the minimum stock density in 2001 was 98.24 kg/km^2 in spring, in 2002 was 125.45 kg/km^2 in winter. （2） The average annual stock density of Japanese flying squid, Todarodes pacificus was the maximum among Cephalopod, 145.07 kg/km^2 in 2001 and 101.85 kg/km^2 in 2002. The stock density of octopus was the minimum among Cephalopod, 4.69 kg/km^2 in 2001 and 2.54 kg/km^2 in 2002. （3） The biomass of Cephalopod at continuental shelf area of the East China Sea was 375 384.90 t and 172 692.90 t respectively in 2001 and 2002, of which the MSY was 238 553.56 t and 144 277.31 t, respectively.