Advances in fish passage in the Great Lakes basin

Y Addressing the impact of dams and other water control structures on fish communities and aquatic ecosystems is a major concern for fisheries managers in the Laurentian Great Lakes. Although nature-like and technical fishways (i.e., vertical slot, pool and weir, Denil) and, when suitable, barrier removals have been implemented across the basin, these fish passage applications are vastly outnumbered by barriers to fish movement. Lowermost barriers are the first structure that blocks fish passage within a tributary; and, in the Laurentian Great Lakes, they present a unique situation where restricting access to upstream habitat is a major component of a half a century long strategy to control invasive sea lamprey Petromyzon marinus. Solutions for passage at lowermost barriers must therefore consider alternative management actions surrounding increased connectivity and invasive species control. These actions are underlined by the primary management objective of enhancing production/diversity of native and recreationally desirable fishes. This review surveys the current state of fish passage technologies deployed in the Laurentian Great Lakes and other fish passage solutions under development, providing a reference for resource managers making decisions about barriers and fish passage that are critical for invasive species control and fishery restoration. (C) 2020 The Authors. Published by Elsevier B.V. on behalf of International Association for Great Lakes Research.

Automated summary

Addressing the impact of dams and other water control structures on fish communities and aquatic ecosystems is a major concern for fisheries managers in the Laurentian Great Lakes. The current fish passage applications are vastly outnumbered by barriers to fish movement, highlighting the need for alternative management actions surrounding increased connectivity and invasive species control.