Comparative passage of northern pike (Esox lucius) in standard Denil and steeppass fishways

A standard Denil fishway and a steeppass fishway were operated adjacent to each other at a marsh in east-central Saskatchewan to determine how effectively these designs pass northern pike. Both fishways consisted of three sections from 8.2 to 10.4 metres in length at slopes of 10%. A total of 87 pike ascended the two fishways during the study in the spring of 1990. The fishways were operated at two flows,.045 m;There were no differences between fishways with respect to length, sex of spawning condition of ascending pike. Average size of pike that ascended the fishways was less than pike that did not ascend the fishways. There was no difference between ascending and nonascending pike with respect to sex or spawning condition. Pike ascended the fishways with little delay after they entered the fishway area, with a median delay time of 2.75 hours.;The channel downstream of the fishways was blocked with a two-way trap to monitor fish movements in the vicinity of the fishways. Forty-nine pike were tagged as they entered the study area and were later recaptured. Of these, twelve ascended the steeppass fishway and seven ascended the standard Denil fishway for an aggregate passage efficiency of 39%. The highest passage rate observed was in the steeppass fishway at the high flow regime, with an efficiency of 32%.