Elucidation of migration routes of radiocesium to freshwater fish using the model water area

Miura, Tomisato*; Nakanishi, Takahiro   ; Sakuma, Kazuyuki   

From the analysis of yamame trout and aquatic insects inhabiting the Ukedo River system, it is speculated that the main migration route to yamame trout is via non-carnivorous aquatic insects. And, analysis of the yamame trout pond revealed a negative correlation between yamame trout body weight and radiocesium concentration, suggesting that individuals unable to receive non-contaminated food prey on benthos inhabiting the bottom of the pond. In this study, we analyze the concentration and stable isotope composition of radiocesium in yamame trout, aquatic insects, and benthos, and analyze the migration route of radiocesium to yamame trout.