Fishing grounds of longtail tuna in the Sea of Japan

2016 Fiscal Year Final Research Report

• Project/Area Number: 15K18739
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Aquatic bioproduction science
• Research Institution: Fisheries Research and Education Agency (2016); National Fisheries University (2015)
• Principal Investigator: Tanoue Hideaki 国立研究開発法人水産研究・教育機構, 水産大学校, 助教 (40601084)
• Research Collaborator: MOHRI Masahiko ; MANABE Ryotaro
• Project Period (FY): 2015-04-01 – 2017-03-31
• Keywords: 漁業情報学

Outline of Final Research Achievements

Recently, the increased catch of the longtail tunas in the Sea of Japan has led to the increased risk for juvenile bluefin tunas whose forms are similar to the longtail tunas to be confused and caught. Questionnaire and hearing survey have been conducted through this study to understand how the fishing ground of the longtail tunas is formed. The results show that the longtail tunas in the Sea of Japan are mainly caught in Hokuriku district and the area to the south. The fishing season is found to be from May to December, and the catch is the largest in September (at 25.3 ± 1.6 ℃) according to the slip showing the fish catches by set net in Futaoi-jima island. Their gonado-somatic index is the highest in June for female and in July for male, and a systematic observation shows that their oviposition and spermiation occur in July. The data from pop-up archival transmitting tag indicate the possibility that they are moving in the water area near warm shores in October.

Free Research Field

水産資源管理学