Graham Sustainability Institute

Restoring native fish migrations while controlling invasive species: an optimization approach

Project Photo


Peter McIntyre, University of Wisconsin
Patrick Doran, The Nature Conservancy Great Lakes Project
Matt Diebel, Wisconsin Department of Natural Resources

Additional Core Team Members

Margaret Guyette, Allison Moody, Tom Neeson, Michael Ferris and Adam Hinterthuer, University of Wisconsin
Mary Khoury and Matt Herbert, The Nature Conservancy Great Lakes Project

Project Summary

Fish and fisheries in the Great Lakes benefit enormously from access to productive spawning grounds in tributary rivers. Currently, access to a large majority of the Great Lakes watershed is blocked by dams and road crossings. These barriers also serve to limit the spread of certain invasive species such as sea lamprey and round goby. Rising political will and funding to remove barriers provide an opportunity to restore tributary connections, but the management community lacks a consistent framework for selecting projects that maximize benefits to native fishes while minimizing costs of removals and subsequent species invasions.

The project team is building on previous work to map tributary barriers throughout the Great Lakes and develop a computer model to identify the optimal set of barrier removals given a specified budget.

With funding from the U‐M Water Center, the team is further refining its barrier removal model by accounting for the spatial variation in the diversity of native migratory fish species that could benefit from barrier removal, landscape impacts on tributary habitat condition, improved estimates of barrier removal costs and potential for round goby invasion. By accounting for all of these factors in a transparent and objective way across the Great Lakes basin, the improved model addressed the needs of agencies and nongovernmental organizations for a decision‐support tool to identify cost‐effective barrier removals that can boost fisheries without jeopardizing control of invasive species.