National Research Institute of Far Seas Fisheries, Fisheries Research Agency, 5-7-1 Orido, Shimizu, Shizuoka 424-8633, Japan. tamaki
J Fish Biol. 2010 Jun;76(10):2418-33. doi: 10.1111/j.1095-8649.2010.02628.x.
Species composition and food habits of four istiophorid billfishes were investigated and compared in three different tropical areas of the eastern North Pacific Ocean by longline operations from September to November 2004. Sailfish Istiophorus platypterus, shortbill spearfish Tetrapturus angustirostris and blue marlin Makaira nigricans had specific habitat preferences and mainly occurred in the near-continent area (13-16 degrees N; 103-107 degrees W), the open-ocean area (16-18 degrees N; 118-134 degrees W) and the near-equator area (5 degrees N; 104-120 degrees W). Small (<140 cm in lower jaw-fork length) striped marlin Kajikia audax mainly occurred in the near-continent area; however, large (>/=140 cm) individuals occurred throughout all three areas. Prey compositions of large K. audax in the three areas were different from one other reflecting the prey availability in each area. In the open-ocean area, molid fishes were dominant in mass for both large K. audax (49%) and T. angustirostris (73%), and large K. audax also fed on ostraciid (33%) and scombrid fishes (15%). In the near-continent area, tetraodontid fishes were dominant for large and small I. platypterus (54, 57%), and both large and small K. audax also fed on tetraodontid fishes (3, 12%). Large K. audax in this area fed mainly on scombrid fishes (86%). These results indicate that large K. audax show overlaps but little segregations of its prey with other billfishes. In the near-equator area, stomach contents of large K. audax and M. nigricans were few and billfish prey items were thought to be scarce.
2004 年 9 月至 11 月，通过延绳钓作业在北太平洋东部三个不同热带地区调查和比较了四种鲯鳅科鱼类的种类组成和食性。旗鱼 Istiophorus platypterus、短吻枪鱼 Tetrapturus angustirostris 和蓝枪鱼 Makaira nigricans 具有特定的栖息地偏好，主要出现在近大陆区（13-16 度 N；103-107 度 W）、开阔海区（16-18 度 N；118-134 度 W）和近赤道区（5 度 N；104-120 度 W）。小（下颌叉长<140 厘米）条纹枪鱼 Kajikia audax 主要出现在近大陆区；然而，大（>=140 厘米）个体出现在所有三个地区。三个地区大 Kajikia audax 的猎物组成不同，反映了每个地区的猎物可利用性。在开阔海区，大型 Kajikia audax 和 T. angustirostris 的主要食物是鲷科鱼类（分别占 49%和 73%），大型 Kajikia audax 还摄食鲻科鱼类（33%）和鲭科鱼类（15%）。在近大陆区，大型和小型 I. platypterus 的主要食物是鲀科鱼类（54%，57%），大型和小型 Kajikia audax 还摄食鲀科鱼类（3%，12%）。该地区的大型 Kajikia audax 主要以鲭科鱼类为食（86%）。这些结果表明，大型 Kajikia audax 与其他箭鱼的猎物有重叠但很少有分化。在近赤道区，大型 Kajikia audax 和 M. nigricans 的胃内容物很少，箭鱼的猎物似乎很稀缺。
