中东太平洋金枪鱼延绳钓渔获物组成分析

根据2000年9月至2002年8月两年的中东太平洋金枪鱼延绳钓探捕调查结果，对延绳钓渔获物组成进行了初步分析。结果显示，延绳钓的主要渔获种类有肥壮金枪鱼(Thunnus obesus)和黄鳍金怆鱼(Thunnus albacares)等15种大洋性鱼类，渔获物中金枪鱼类分别占重量和尾数的76．41％和76．91％，旗鱼类占11．05％和7．83％．鲨鱼类占10．80％和12．08％，其他鱼类占1．73％和3．18％。相对重要性指标(IRI)表明，延绳钓渔业以肥壮金枪鱼和黄鳍金枪鱼为目标鱼种，其他大型中上层经济鱼类为兼捕对象。各渔获种类的渔获重量组成比例月间变化和海域变化明显。

Preliminary analyses on the composition of catches captured by tuna longline gear from the Eastern and Central Pacific Ocean

Based on the two years test fishing in the Eastern and Central Pacific Ocean (ECPO) from Sep., 2000 to Aug., 2002, the composition of catches captured by tuna longline gear was investigated. The results indicated that 15 species of pelagic fishes including bigeye tuna(Thunnus obesus)and yellowfin tuna(Thunnus albacares)were caught mainly by longline. The tuna is predominant in weight and individual number in the catches, accounting for 76.41% and 76.91% respectively, then swordfish and marlins for 11.05% and 7.83%, sharks for 10.80% and 12.08%, other species were considerably low in proportion for 1.73% and 3.18%. The index of relative importance (IRI) showed that bigeye tuna and yellowfin tuna were the major target species, and other large economic pelagic fishes were the by-catch species in longline fishing. The changes of species yield in proportion of catches were evident monthly and spatially. This longlining survey will provide the primary data for the further exploitation and reasonable utilization of the tuna resource in ECPO.