著者

後藤 暁彦 黒木 真理 森田 健太郎

出版者

一般社団法人 日本魚類学会

雑誌

魚類学雑誌 (ISSN:00215090)

巻号頁・発行日

vol.67, no.2, pp.241-245, 2020-11-05 (Released:2020-11-14)

参考文献数

20

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A non-native brown trout Salmo trutta (407 mm in fork length, 717 g in body weight) was collected from the Otsukushinai River, southern Hokkaido, Japan, in 2019. This specimen was an immature male (0.4 g in gonad weight). The otolith Sr:Ca ratio profile and annual rings suggested that the specimen had migrated to the sea at the age of 4+ years and ascended the Otsukushinai River in the year of the seaward migration. This study is the first record of invasion of anadromous brown trout through the sea in Japan.