Connecting wild salmon and steelhead to the ocean with cables Updated at Share This The following is a news release and photo from the Idaho Department of Fish and Game. LEWISTON — What does a large fish trap attached to a main highway bridge have to do with wild salmon and steelhead migration? Each late winter, a Fish and Game crew prepares and constructs a nearly 100-foot long fish trap. They tow it from a storage facility downstream of Clarkston, Washington to the Highway 12 (“Blue”) Bridge that spans the Snake River between Lewiston, Idaho and Clarkston, Washington. This ritual began at this site in 1984 and continues to this day.