The Department of Natural Resources today announced that, for approximately three weeks in mid-August, a study of the population of juvenile lake sturgeon in Black Lake (Cheboygan County) will be occurring.
The tag-and-recapture study conducted by the DNR’s Fisheries Division will consist of marking all netted sturgeon and determining the ratio of marked to unmarked fish to understand current population abundance and size structure.
Lake sturgeon rehabilitation has been ongoing in the Black River and Black Lake for more than a decade through the cooperative efforts of the DNR, Michigan State University, Sturgeon for Tomorrow and Tower-Kleber Limited Partnership. This has included rearing sturgeon in a streamside hatchery on the Black River near Kleber Dam. Fingerling sturgeon from the hatchery have been stocked in the Cheboygan River watershed for more than a decade to supplement declining wild fish populations. Such stocking efforts have been focused on Burt, Mullett and Black lakes and their associated rivers, with an emphasis on Black Lake. Previous assessments of juvenile sturgeon populations in Burt and Mullett lakes have shown excellent survival of young sturgeon, and this year’s assessment will center on Black Lake.
“Our goal is to assess how well our recent stocking efforts for lake sturgeon have fared in Black Lake,” said Ed Baker, fisheries research biologist. “We will be able to determine a population size of juvenile fish and their growth, as well as the proportion of stocked sturgeon compared to wild sturgeon based on marks the young fish receive in the hatchery prior to stocking.”
This information will allow fisheries managers to adjust future stocking levels and even determine eventual population goals.
Lake sturgeon will be captured in gill nets placed across Black Lake in depths and temperatures suitable for this species. These will include tandem gill nets 600 feet long tied together with either 3- or 4-inch mesh. The large mesh size should preclude species such as walleye or bass from entering the nets, and should limit the number of adult lake sturgeon getting tangled as well. Nets will be monitored hourly by crews during the day to reduce fish stress or mortality. Gill nets will be marked with large DNR buoys and will not be left out overnight. Each fish will be marked with a unique tag for future identification purposes.
“This is an important step in the Black Lake sturgeon rehabilitation efforts,” said Dave Borgeson, fisheries unit supervisor from Gaylord. “A tremendous amount of effort has been invested in this species in this area for more than decade, and determining survival and growth of stocked fish will help determine future project direction.”
For more information on lake sturgeon in Michigan, visit www.michigan.gov/sturgeon.
Logo courtesy Michigan Department of Natural Resources