Definition of 降河回遊 (こうかかいゆう)
こうかかいゆう
                        降河回遊
こうかかいゆう
koukakaiyuu
noun
•
        
downstream migration
Related Kanji
| 降 | descend, precipitate, fall, surrender | 
| 河 | river | 
| 回 | -times, round, game, revolve, counter for occurrences | 
| 遊 | play |