A new study begins this month on Saginaw Bay, using acoustic transmitters that will be implanted in walleye to help researchers with the Michigan Department of Natural Resources, Michigan State University and several partner agencies obtain data about where the fish spawn.
Fish in such telemetry projects have acoustic transmitters affixed to them. Each transmitter then beeps a fish-specific code every few minutes. Acoustic receivers deployed in Lake Huron decode the tag beeps and log when fish tags are detected. The network of acoustic receivers in Saginaw Bay includes receivers in the mouths of rivers to listen for tagged fish moving to spawning grounds and receivers in Saginaw Bay to determine where walleye may be spawning.
Having a better understanding of relative sources of natural reproduction for walleye will help fishery managers determine which rivers and reefs to protect and, when needed, where to invest in actions that enhance and improve fish habitat.
Volunteer charter boat operations are assisting in the study by collecting the walleye hook and line in May while the fish from all spawning sources are mixed post-spawn, but before any leave the bay. Then when the fish return for spawning next spring, their locations will be logged in the receivers. There are at least 15 rivers and five offshore reefs that are likely sources of walleye spawning.
“The recovery of the Saginaw Bay walleye population is one of the great fishery management success stories of our time,” said Dave Fielder, a DNR fisheries research biologist. “However, we don’t fully know where all that natural reproduction takes place.”
Implanting the transmitters
Plans call for 150 walleye to be outfitted with transmitters this year, plus 200 more in 2023. The surgical procedure includes immobilizing the fish using low-voltage electricity and implanting a transmitter in the body cavity
