Jan. 30, 2018

Contact: Darren Kramer, 906-786-2351 or Troy Zorn, 906-249-1611, ext. 308

New study to track movements of walleye and lake whitefish in and around Green Bay

The U.S. Geological Survey, the University of Wisconsin-Stevens Point, the Wisconsin Department of Natural Resources, the Michigan Department of Natural Resources and the Great Lakes Acoustic Telemetry Observation System are collaborating on a large-scale study to determine movements of walleye and lake whitefish in and around Green Bay.

This important research will provide new information regarding seasonal movements of individual fish and help determine which spawning locations are critical to the sport and commercial fisheries for these species.

The study consists of implanting transmitters into 300 walleye and 400 lake whitefish. The transmitters are black cylinders (as shown in the attached photo, below) that are surgically implanted into the body cavity of the fish. These transmitters periodically send out a coded signal that is detected by an array of more than 150 acoustic receivers located in and around Green Bay. The transmitters will allow tracking of fish for up to four years. A small temperature sensor, attached to each transmitter, will also allow researchers to better understand the water temperature preferences of individual fish along with likely water depths used by each fish.

"We are excited to partner on research that will help us better understand the movement patterns of and habitats used by walleye and lake whitefish,” said Troy Zorn, Michigan DNR fisheries research biologist. “Through previous tagging projects, we have some general information on walleye and lake whitefish movements, but the more sensitive information from this study will greatly increase our knowledge on current movement patterns. It’s a timely study since ecological conditions have changed so much in recent decades. The information gathered will help us sustain these important fisheries into the future."

Each fish implanted with a transmitter also will receive an external orange loop tag (as shown in Figure 2), indicating a $100 reward for return of the transmitter. Recovered internal transmitters can be implanted in other fish to continue tracking efforts.

If one of these tagged fish is legally harvested, anglers are asked not to freeze the fish and to contact Dr. Dan Isermann with University of Wisconsin-Stevens Point at 715-346-2178 or dan.isermann@uwsp.edu to coordinate the tag's return and reward.

/Note to editors: Photo examples of the internal transmitter and external orange loop tag anglers may see are available below. Images courtesy of the Wisconsin Department of Natural Resources./

The Michigan Department of Natural Resources is committed to the conservation, protection, management, use and enjoyment of the state’s natural and cultural resources for current and future generations. For more information, go to www.michigan.gov/dnr.