Masu Salmon
Masu salmon (Oncorhynchus masou), also called cherry salmon, live half their life in a river as freshwater fish before migrating to the ocean. They return to their home river to spawn after two to three years at sea. In Japanese, they are called sakura masu (cherry salmon) because they turn pink (the color of cherry blossoms) on reaching maturity, and because they are usually caught during spring (cherry-blossom season), when they return to their river spawning grounds. Some masu salmon never leave their home river; these fish are called yamame (yamabe in Hokkaido). Masu salmon have a very limited range, staying in coastal waters off northern Japan after reaching maturity.