Checking in on Young Walleye: Michigan DNR Begins Fall Surveys in September

If you’re on the water in late September to early October, be on the lookout for Michigan Department of Natural Resources personnel conducting nighttime walleye recruitment surveys. Fisheries managers use these surveys to determine whether walleye that hatched in the spring (known as young-of-year) were born in the wild or were stocked, as well as how many are present in an area. This information about the status of young walleye in lakes helps the DNR make well-informed management decisions.
Using electrofishing boats at night, crews will survey shallow areas near the shoreline of lakes with the goal of capturing juvenile walleye. Walleye prefer cooler, deeper areas of lakes during the day but move into shallow, nearshore areas at night, making nighttime surveys more efficient. On larger lakes, two or more electrofishing crews using separate boats may operate at the same time to cover more area. The crews will work on a subsample of Michigan lakes that have been stocked with walleye, as well as lakes that have not.
Biologists also collect and keep a sample of young-of-year walleye from stocked lakes to determine whether the fish are primarily reproducing naturally or if young-of-year are from stocking. All other walleye will be released unharmed. Walleye that are stocked in these lakes are marked with oxytetracycline, a chemical marker that can be observed within captured fish by using a microscope with an ultraviolet light source in a laboratory setting. Read more