Contact(s): Dave Boyarski, DNR northern Lake Michigan fisheries supervisor, 920-746-2865; David.Boyarski@Wisconsin.gov; Brad Eggold, DNR southern Lake Michigan fisheries supervisor, 414-382-7921, Bradley.Eggold@wisconsin.gov; Jennifer Sereno, DNR communications, 608-770-8084, Jennifer.Sereno@wisconsin.gov
October 20, 2015
MILWAUKEE - The 2015 fall chinook spawning run in the Wisconsin waters of Lake Michigan is winding down and has produced enough eggs to supply hatcheries operated by the Wisconsin Department of Natural Resources and support neighboring states.
Although the 2015 spawning run has been later than usual this year and fish numbers have been down as expected, DNR fisheries staff at the Strawberry Creek Chinook Facility in Sturgeon Bay met their goal of 1.5 million eggs needed to produce the approximately 810,000 fish planned for spring 2016 stocking. Meanwhile, the Root River Steelhead Facility in Racine provided 450,000 eggs to the state of Indiana and the C.D. "Buzz" Besadny Anadromous Fish Facility in Kewaunee provided 100,000 eggs to the state of Illinois.
Dave Boyarski, northern Lake Michigan fisheries supervisor, said one last chinook egg collection will take place at Strawberry Creek on Thursday to ensure genetics from some of the later spawning fish are captured.
"Using this phased approach is a key part of our brood stock management program," Boyarski said. "By collecting eggs throughout the run, we ensure maximum genetic diversity in our spawning stock. We have been pleased with the returns at Strawberry Creek, which remains our primary location for chinook egg collection. We are also fortunate to have the Root River and Besadny facilities serving as backups and providing help to neighboring states this year."
Brad Eggold, DNR southern Lake Michigan fisheries supervisor, said fisheries managers anticipated this year's chinook spawning run would be off from recent record highs because in 2013, Wisconsin decreased stocking levels by 30 percent.
"We reduced stocking - as did other states - to better match the availability of alewives, the main food source for chinook," Eggold said. "This is part of the collaborative management we practice on Lake Michigan to help ensure a healthy and sustainable sport fishery that benefits anglers throughout the region."
This year, it is in large part fish from the reduced 2013 stocking class that made their way back home to spawn. Boyarski said this year's run still occurred within the typical four-week window, although lack of rain likely played a role in the delayed start.
"The return of fish each fall can be affected by a variety of conditions including water temperature, lake levels and stream flow," he said.
Going forward, the fisheries managers said, the department will continue to rely on the best available population estimates and models from a variety of state and federal agencies including the U.S. Fish and Wildlife Service and U.S. Geological Survey to continue to balance salmon stocking with alewife numbers. Although chinook were originally stocked in the late 1960s to help control alewife numbers, alewives are now at historic lows due to the effects of zebra and quagga mussels as well as predation from previously high numbers of chinook.
At least one bright spot is that recent USGS fall surveys indicate that the alewives had a successful 2015 spawning season this spring and young of the year alewives are now present. Final alewife abundance estimates for 2015 are expected in March.
"The bottom line for anglers is that we are trying to maintain an equilibrium of predators and prey that has produced harvests the last two years that are close to the 46 year long-term average catch," Eggold said. "These average catches are more sustainable and necessary to maintain a productive trout and salmon fishery based on the changing ecology of the lake."