From lake trout to invasive species, discover what Michigan’s waters revealed in this year’s DNR surveys.
Photo: Research tech Lydia Doerr with a large lake trout caught during survey at Isle Royale, June 2024. Credit: MDNR
January 22, 2025 – Michigan’s Department of Natural Resources (DNR) has completed its annual Great Lakes fisheries surveys, conducted from April to November 2024. These surveys, covering Lake Superior, Lake Michigan, Lake Huron, and the St. Clair-Detroit River System, are critical for understanding fish populations, invasive species, and the health of aquatic ecosystems. Here are highlights from this year’s findings:
Lake Superior and Northern Lake Michigan
Crews focused on lake trout, whitefish, and burbot, deploying over 257,000 feet of gill net across Lake Superior. Data showed stable adult lake trout populations and slight increases in juvenile recruitment in select areas. Deep-water surveys around Isle Royale and remote sites like Klondike Reef revealed strong trout activity. In Lake Michigan’s Little and Big Bay de Noc, surveys collected data to assess fish community changes and population trends for species like walleye, yellow perch, and invasive species, though specific changes were not detailed.
Lake Michigan
The Charlevoix Fisheries Research Station concentrated on lake trout, yellow perch, and forage fish. A spring gill net survey covered eight ports, yielding data on over 5,000 fish. Hydroacoustic surveys showed stable alewife populations but low reproduction rates for young fish. Bottom trawl surveys in ports like Grand Haven and Pentwater identified trends in nearshore species and invasive activity.
Lake Huron
Lake trout surveys in northern Lake Huron showed consistent adult populations, while young lake trout were mainly found in the northern areas. Cisco restoration efforts in Saginaw Bay saw positive indicators, with significant young walleye numbers recorded. However, yellow perch populations in the bay remained low. In the Les Cheneaux Islands, yellow perch populations improved slightly.
St. Clair-Detroit River System
The St. Clair River and Lake St. Clair surveys revealed distinct subpopulations of smallmouth bass and a strong presence of young lake sturgeon. Collaborative efforts with Ontario and federal agencies monitored larger fish in offshore areas and the forage fish community. Lake Erie surveys highlighted strong walleye reproduction and promising yellow perch numbers.
Looking Ahead
The data from these surveys informs fishery management decisions, including stocking levels and catch limits. Collaborations with academic institutions continue to enhance research on Michigan’s aquatic ecosystems. For more information, visit Michigan.gov/Fishing.