基于渔业声学和灯光罩网的南海中南部鸢乌贼资源评估

Estimation of purpleback flying squid （Sthenoteuthis oualaniensis） resource in the central and southern South China Sea based on fisheries acoustics and light-falling net

为查明南海外海鸢乌贼（Sthenoteuthis oualaniensis）的资源量及其分布，2012年秋季和2013年春季，利用科学探鱼仪（Simrad EY60）结合灯光罩网采样方法对南海中南部（16°N-5°N）鸢乌贼资源进行了声学调查与评估。在确定该方法的有效性基础上，调查结果显示，1）2012年秋季鸢乌贼丰度和资源量分别是3．26×10^10 inds和2．14×10^6 t，变异系数是23％；鸢乌贼个体胴长范围、平均胴长和平均质量分别是62～248mm、127mm和65g；秋季，鸢乌贼从南至北均有分布，主要分布在8．0°N以北和114．0°E以西海域；最高数量密度是1．7×10^6inds·nmi^-2（6．5°N，111．0°-111.1°E），最高资源量密度是85t．nmi^-2（15．0°N，114．35°114．45°E）；2）2013年春季鸢乌贼丰度和资源量分别是2．98×10^10 inds和2．44×^6t，变异系数是23％；鸢乌贼个体胴长范围、平均胴长和平均体质量分别是73～238mm、122mm和82g；春季，鸢乌贼从南至北亦均有分布，主要分布在11．0°N以北；最高数量密度是3．3×10^6inds·nmi^-2（13．0°N，116．55°-116．65°E），最高资源量密度是60t·nmi^-2（15．0°N，115．25°-115．35°E）。研究表明，南海外海鸢乌贼资源量至少在2．00×10^6t以上；与2012年秋季相比，2013年春季鸢乌贼密集区向东北移动。

In order to identify the abundance and distribution of Sthenoteuthis oualaniensis in the open waters of South China Sea, two acoustical surveys were conducted using scientific echosounder （Simrad EY60） in the area of central and southern South China Sea （16°-5°N） in the autumn in 2012 and the spring in 2013. The survey results showed： （1） The abundance and biomass orS. oualaniensis in the autumn in 2012 were 3.26×10^10 inds and 2.14×10^6 t respectively and the coefficient of variation was 23%; the mangle length range, mean mantle length and mean body mass of S. oualaniensis were 62-248 mm, 127 mm and 65 g, respectively; in the autumn S. oualaniensis population distributed in the entire central and southern South China Sea, mainly distributed north of 8.0°N and 114.0°E area; the maximum abundance density and biomass density of S. oualaniensis were 1.7×10^6 inds.nmi^-2 （6.5°N, 111.0°-111.1°E） and 85 t.nmi^-2 （15.0°N, 114.35°-114.45°E） respectively. （2） The abundance and biomass of S. oualaniensis in the spring in 2013 were 2.98 × 10^10 inds and 2.44× 10^6 t respectively and coefficient of variation was 23%; the mangle length range, mean mantle length and mean body mass of Sthenoteuthis oualaniensis were 73-238 mm, 122 mm and 82 g respectively; in the spring S. oualaniensis population also distributed in the entire central and southern South China Sea, mainly distributed north of 11.0°N area; the maximum abundance density and biomass density of S. oualaniensis were 3.3 × 10^6 inds.nmi^-2 （13.0°N, 116.55°- 116.65°E） and 60 t·nmi^-2 （15.0°N, 115.25°-115.35°E） respectively. The research results indicated that the biomass of S. oualaniensis resource was not less than 2.00×10^6 t in the open water of South China Sea; compared with the autumn in 2012, concentrated ground of S. oualaniensis moved north and east in the spring in 2013.