The development of the method to estimate the experienced environment by fish using stable isotope analysis

2015 Fiscal Year Final Research Report

• Project/Area Number: 25450279
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Aquatic bioproduction science
• Research Institution: Kitasato University
• Principal Investigator: HAYASHIZAKI Ken-ichi 北里大学, 海洋生命科学部, 准教授 (80208636)
• Research Collaborator: SHIOZAKI Takuhei 東京大学, 大気海洋研究所, 特別研究員 (90569849) ; IZUKA Takashi 神奈川県水産技術センター内, 水面試験場, 主任研究員
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: サケ / 安定同位体 / 環境変動 / 魚類 / 年齢 / 成長 / 生残 / 鱗

Outline of Final Research Achievements

The isotopic fractionation factors and turnover rates of young landlocked masu salmon and young char were determined. Carbon and nitrogen stable isotope ratios of age 3 chum salmon scales are measured using archived scales collected from 1975 through 2014 in Iwate prefecture. The variation of both stable isotope ratios tended to be high in recent years, which suggested that the composition of available food items for chum salmon in Bering and Gulf of Alaska form Iwate prefecture could be shifted in the period. The recruitment of age 1 chum salmon from Iwate prefecture was estimated by VPA like method. Even in the period of high abundance of Iwate chum salmon the recruitment levels could be low as in the low abundance period. Moreover the density effect on Iwate chum salmon seems to be still exit even in the recent year.

Free Research Field

水産資源解析学