Session D1: Towards Effective, Bi-Directional Selective Fish Passage

Abstract: Barriers interfere with aquatic connectivity by preventing or limiting migratory fishes from spawning and other life history processes, and there is increasing pressure to restore connectivity. However, conflicting management objectives exist in many jurisdictions where barriers to fish movement inhibit the restoration of native fishes but protect native fish communities above barriers from undesirable invasive species. In the Laurentian Great Lakes, barriers are an important management tool in the control of invasive Sea Lampreys. Sea Lampreys remain highly destructive in the Great Lakes, and are a constant threat to a 7 billion dollar fishery. Developing selective, effective bi-directional fish passage to remove Sea Lampreys while allowing the passage of native fishes has become an issue of great importance for Great Lakes fisheries managers. To date, efforts have included a variety of approaches including velocity barriers, seasonal barriers, trap-and-sort fishways, and eel ladders. The integration of emerging technologies, such as push-pull and electrical and pheromone guidance and advances in engineering, such as eel-style ladder traps are providing hope that better selective, effective bi-directional fish passage solutions are possible. The Great Lakes Fishery Commission is developing a research theme specific to selective bi-directional fish passage in the hopes of resolving the conflict between aquatic fragmentation and invasive species control