Managing Fish Passages and Barriers on Canadian Tributaries to the Laurentian Great Lakes
Fish Passage Policy and Technology: Proceedings of a Symposium
American Fisheries Society
The 1800s settlement of the Laurentian Great Lakes caused the construction of thousands of dams and weirs for water power. After a mid-1950s 100 year storm which destroyed most barriers, resource agencies rebuilt structures especially for flood control, but occasionally to block fish migrations. The arrival of desired (e.g. Oncorhynchus spp) and undesired (e.g. Petromyzon marimus) species forced biologists and engineers to rethink the design and operation of barriers and fish passages. Conflicts arose when passage design and/or operation allowed upstream migration of undesired species yet blocked migration of desired species. As well, dam removal and aquatic habitat renewal to increase production of salmonids increased production of sea lamprey. Close cooperation amongst agencies at planning, design, and operation stages has reduced conflict between programs and contributed to more holistic management of streams systems.