Project/Area Number |
17K07924
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Multi-year Fund |
Section | 一般 |
Research Field |
Aquatic bioproduction science
|
Research Institution | Fisheries Research and Education Agency |
Principal Investigator |
Suyama Satohsi 国立研究開発法人水産研究・教育機構, 東北区水産研究所, グループ長 (70344322)
|
Co-Investigator(Kenkyū-buntansha) |
冨士 泰期 国立研究開発法人水産研究・教育機構, 国際水産資源研究所, 研究員 (50792660)
|
Project Period (FY) |
2017-04-01 – 2020-03-31
|
Project Status |
Completed (Fiscal Year 2019)
|
Budget Amount *help |
¥4,550,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥1,050,000)
Fiscal Year 2019: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000)
Fiscal Year 2018: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
Fiscal Year 2017: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
|
Keywords | サンマ / 成熟 / 産卵 / 履歴 / 北太平洋 / 浮魚 / 水産資源 / 1歳魚 / 耳石 / 年輪 / 回遊 / 年齢 / 産卵履歴 / 成長 / 生殖腺 / 初回成熟 / 耳石日周輪 |
Outline of Final Research Achievements |
Pacific saury is widely distributed in the North Pacific Ocean. The growth rates of this species are known to vary between western and eastern habitat. We investigated the effects of different growing areas and growth on maturation based on the survey conducted in central to western North Pacific in June and July and January to March. Growth rate in age-0 fish collected in west of 160°E was higher than that of fish collected in the east of 160°E. Percentage of the age-1 fish that had spawning experience in the west of 160°E was also higher than that of in the east of 160°E. Hatch periods were estimated from October to March for age-0 and age-1 fish. However, few of age-1 fish hatched in early period of spawning season, October and November, were occurred in the west longitude area. The age-0 fish that hatched in early spawning season and grew in the west longitude area were considered to migrate to westward to next year.
|
Academic Significance and Societal Importance of the Research Achievements |
サンマは日本では重要な漁獲対象魚となっているが、漁獲量は年によって大きく変動している。また、秋の味覚の代表として、毎年の漁況の予測や漁獲量の推移は国民の関心も高い。2000年代は20万トンを超えていた漁獲量も2010年以降減少を続け、2019年は1950年以降最低の数値となった。サンマは北太平洋に広く分布しており、海域によって成長速度が異なるほか、成熟過程、特に初回成熟年齢が成長に影響を及ぼしていると考えられる。本課題では海域による成長、成熟特性の海域差を明らかにし、その違いが成熟に及ぼす影響を明らかにする。また、産卵する個体が行わない個体と回遊様式が異なるか否かを検討する。
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