| 摘要 |
PROBLEM TO BE SOLVED: To protect eels by forming a fishway system for young eel having a simple structure in an estuary barrage. SOLUTION: The fishway system for young eel is constituted of a guide water supply unit 3 provided with a guide water tank 3a on the barrage 1, a channel unit 7 provided with an aqueduct pipe 8 obliquely laid in the downstream side of the barrage, a waterborne fish collective unit 5 on the water surface in the downstream side of the barrage, and a guide unit 9 guiding young eel to run up to the barrage to the upstream side. Running up of young eel has been obstructed so far by the barrage or the like, but the system makes use of the usual behavior of eel to facilitate running up of eel by installing simple equipment. The fish collective unit 5 moves up and down in accordance with the downstream tidal change. The fish collective unit can be always set a float in a correct posture on the water surface by providing the aqueduct pipe with flexibility or by making the pipe freely bendable at the joint. COPYRIGHT: (C)2003,JPO
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