DETROIT – The U.S. Army Corps of Engineers (USACE) Detroit District and Great Lakes Fishery Commission (GLFC) are pleased to announce the completion of a $1.67 million permanent sea lamprey trap on the East Branch Au Gres River in Iosco County, Michigan. The completion of the project represents a long-standing partnership between USACE and GLFC to control invasive sea lampreys and protect the $7 billion Great Lakes fishery.
Sea lampreys, parasitic fish that suck blood from other fish (e.g., lake trout and Pacific salmon), invaded the Great Lakes through shipping canals and devastated Great Lakes fisheries in the mid-1900s. Each sea lamprey can kill up to 40 pounds of fish per year. An estimated 4,500 sea lampreys enter Lake Huron from the East Branch Au Gres River each year. The Great Lakes Fishery Commission coordinates the sea lamprey control program that has reduced populations in the Great Lakes by about 90% since they first invaded, saving nearly 100 million pounds of fish each year.
Since sea lampreys are most vulnerable to capture as they move from lakes into tributaries to spawn, the control program relies on physical barriers to block their upstream migration during the spring, thereby reducing the population. Specially designed traps are built into or placed immediately downstream of sea lamprey barriers to remove the spawning sea lampreys from the system and support assessment efforts of the control program.
“Historically, portable assessment traps were operated in the East Branch Au Gres River, however the capture rate was quite low,” said Steve Check, U.S. Army Corps of Engineers, Detroit District project manager. “The new permanent trap was purposefully constructed to create higher water flows at the entrance to attract sea lampreys, which we expect to result in much higher catch rates.”
“We use every tool we can do keep the population of sea lampreys in check,” said GLFC Chair Jim McKane. “Traps not only remove sea lampreys from the system before they can spawn, but also provide a critical way to assess the adult population and gauge the success of the sea lamprey control program. The East Branch Au Gres River is one of nearly 60 tributaries trapped as part of the control program’s network and we look forward to seeing this new trap in operation this spring. We appreciate the support from Congressman Jack Bergman and Michigan Senators Debbie Stabenow and Gary Peters for their work to protect and improve the Great Lakes.”
Check continued: “The new East Branch Au Gres trap will ultimately serve as a model for similar trap construction projects in the future. It is a low-cost, versatile design that will only require minor adjustments to work in other systems and the maintenance requirements are relatively minor.”
The project was funded under the Great Lakes Fishery and Ecosystem Restoration Program (GLFER), which is carried out by the USACE in partnership with the GLFC. Through the program, state, federal, and tribal representatives solicit, develop, and prioritize projects for construction by USACE. Projects eligible under the GLFER authority include those that involve aquatic and terrestrial habitat restoration that promote the natural reproduction and stability of fish communities, as well as those that aid in the control of the introduction or spread of invasive species in the Great Lakes.
The contractor, Great Lakes Dock and Material, LLC., based in Muskegon, Michigan, began construction on the project in November 2022. USACE approved the completion of the project on Jan. 24, 2023, with plans to have the contractor return to the site in the spring to complete grass planting and seeding.
Additional federal funding for the project was made possible by the Great Lakes Restoration Initiative (GLRI), the Michigan Department of Natural Resources provided the property for the trap, and the U.S. Fish and Wildlife Service will oversee maintenance of the structure.
The Detroit District provides vital public engineering services in peace and war to secure our Nation, protect the environment, energize our economy, and reduce risks from natural disasters. The GLFER Program is the USACE’s primary program for Great Lakes aquatic ecosystem restoration. Visit https://www.lrd.usace.army.mil/Home/Great-Lakes-Fishery-Ecosystem-Restoration-Program/ for more information
The Great Lakes Fishery Commission is an international organization established by the United States and Canada through the 1954 Convention on Great Lakes Fisheries. The commission has the responsibility to support fisheries research, control the invasive sea lamprey, and facilitate cross-border management. Visit glfc.org to learn more.