北上大堰付設バーチカルスロット式魚道に おけるアユ及びサケの遡上調査

抄録

Fishways are located at each end of the dam across the lower part of the Kitakami River. The fish entrances of each fishway is situated 14m downstream from the foot of the dam, at each end of the dam, and the water flow of each fish entrance reaches to the center of the river through a collection gallery at ebb tide. The vertical slot fishway is 44.6m long with l16 sIots between baffles. The actual velocity of the falling water in a slot varies from l.06m/sec to 2.40m/sec. 732 ayu fish and 90 fish of other species swam up the two fishways at two days of June 12 and 20, 1991. 2,458 chum salmon and 55 fish of other species swam up the two fishways at five days during the period from September 12 to October 23, 1991. It is known from the results that the fishways located at each end of the dam across the lower part of the Kitakami River are navigable for ayu fish, chum salmon, and five other species of fish.