英文摘要 |
Before 1980s, swordfish and striped marlin in the Pacific Ocean were mainly caught by Japanese fishery. Although the catches of swordfish from other countries were relative lower, their catches have been more than that of Japan in recent years. Due to the expanding and increasing effort of Taiwanese large scale longline fishery since 1990s, the catches of swordfish and striped marlin increased substantially. Based on the CPUE calculated from data of fisheries operated in the Pacific Ocean, the CPUE of swordfish and striped marline decreased gradually since mid 1960s. Based on the data of Taiwanese fishery, however, the CPUE of swordfish increased substantially since 2000, while the CPUE of striped marlin were relative stable. The changes in fishing operation of Taiwanese fishery could lead to the difference of CPUEs between Taiwan and other countries. For data analysis of Taiwanese small scale longline fishery, the catch proportions of swordfish and striped marlin increased gradually in recent years. Considering the reporting rates of the logbook, however, this analysis is still preliminary. |