Development of a scheme to reproduce a migration history of Japanese sardine using otolith d18O and a data assimilation model

2017 Fiscal Year Final Research Report

• Project/Area Number: 15H04541
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Aquatic bioproduction science
• Research Institution: The University of Tokyo
• Principal Investigator: Komatsu Kosei 東京大学, 大学院新領域創成科学研究科, 准教授 (30371834)
• Co-Investigator(Kenkyū-buntansha): 瀬藤 聡 国立研究開発法人水産研究・教育機構, 中央水産研究所, グループ長 (10463100) ; 白井 厚太朗 東京大学, 大気海洋研究所, 助教 (70463908) ; 渡邊 千夏子 国立研究開発法人水産研究・教育機構, 中央水産研究所, グループ長 (30371818) ; 銭谷 弘 国立研究開発法人水産研究・教育機構, 中央水産研究所, センター長 (80371954)
• Research Collaborator: SAKAMOTO Tatsuya 東京大学, 大学院新領域創成科学研究科, 日本学術振興会特別研究員(DC2)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: マイワシ / 耳石 / 酸素安定同位体比 / 経験水温 / 回遊履歴

Outline of Final Research Achievements

A scheme reproducing a migration history of Japanese sardine (Sardinops melanostictus) was developed using the stable oxygen isotope (δ18O) in the otolith and a data assimilation model for contributing to clarification of the fluctuation mechanism of the stock-biomass. Juveniles were reared in three different water temperatures over the course of a month. Analysis of otolith δ18O was conducted by extracting the portions formed during the rearing period using a micromill, and it derived a linear relationship between otolith δ18O and ambient water temperature. Coupling of the relationship and a data-assimilative model enabled to reproduce a detailed movement of Japanese sardine with a temporal resolution of 10 days from their spawned region around the Kuroshio to the feeding ground in the subarctic area.

Free Research Field

海洋生態学