Passage of Shad at the Bonneville Fishways

None supplied. From introduction: An evident factor in the decline of the shad is the erection of dams that prevented the fish from ascending streams to reach their natural spawning grounds. Although many of these dams had fish ladders intended to pass fish upstream, the shad generally did not use the ladders. Consequently, a part of the investigation of the Atlantic-coast shad has been a search for suitable methods of passing shad over obstructions. At the beginning of this study the only fishways we knew of that were utilized by shad were those at Bonneville Dam on the Columbia River in the Pacific Northwest, and a special study was made of the passage of shad by those fishways. This paper is a report of that study.