2022 Fiscal Year Final Research Report
The importance of the northern Satsunan area as a spawning and nursery ground of small pelagic migratory fish
Project/Area Number |
20K06186
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Multi-year Fund |
Section | 一般 |
Review Section |
Basic Section 40030:Aquatic bioproduction science-related
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Research Institution | Kagoshima University |
Principal Investigator |
Kume Gen 鹿児島大学, 農水産獣医学域水産学系, 准教授 (00554263)
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Co-Investigator(Kenkyū-buntansha) |
一宮 睦雄 熊本県立大学, 環境共生学部, 教授 (30601918)
小針 統 鹿児島大学, 農水産獣医学域水産学系, 教授 (60336328)
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Project Period (FY) |
2020-04-01 – 2023-03-31
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Keywords | 北部薩南海域 / 湧昇 / 黒潮 / 多獲性浮魚類 |
Outline of Final Research Achievements |
To evaluate the importance of the northern Satsunan area as a spawning and nursery ground for small pelagic migratory fish (Engraulis japonicus, Trachurus japonicus, and Scomber japonicus), we investigated their early life history characteristics. E. japonicus larvae were dominantly occurred. The number of S. japonicus larvae started to increase in 2016, corresponding to the population dynamics of the Pacific stock of the species, which has shown increasing trends in recent years. Densities of larvae were consistently higher in the bay (upwelling area) than in the strait (non-upwelling area). Their diet clearly differed among species. In addition to copepods, S. japonicus larvae fed substantially on appendicularians. The trophic pathway involving appendicularians might support the feeding habits of S. japonicus, promoting its coexistence with other species. Our results provide insights for the fisheries management for small pelagic migratory fish in the Japanese Pacific coastal area.
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Free Research Field |
水産資源学
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Academic Significance and Societal Importance of the Research Achievements |
資源高水準期になると、北部薩南海域にはマイワシの最大規模の産卵場が形成されることが知られている。マサバでも同様の傾向がみられることが分かった。本海域はカタクチイワシ、マアジ、ゴマサバ、資源高水準期のマサバ、マイワシといった多獲性浮魚類の重要な産卵場として利用されていることが明らかとなった。 太平洋沿岸域において黒潮の上流に位置し、かつ、従来考えられてきた東シナ海の主要な産卵場に比べて近接する北部薩南海域は、我が国の太平洋沿岸域の水産資源を支える鍵となる海域である。今回得られた成果は、今後我が国の太平洋沿岸の多獲性浮魚類の資源管理施策を講じていく上で重要な知見であり、学術的かつ社会的意義は大きい。
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