MARQUETTE, Mich. (WOWO) — Michigan is turning to DNA testing to find out whether millions of dollars spent stocking fish are actually paying off, using a method similar to consumer ancestry tests to determine whether stocked fish survive and reproduce in state waters.
The Michigan Department of Natural Resources has begun using genetic testing to trace fish back to their parents, giving fisheries managers a clearer picture of whether stocked fish are contributing to future generations. A pilot program in the Upper Peninsula found the approach can reveal differences in stocking success from one lake to another.
The DNR spent more than $11 million on fish rearing and stocking during the 2024-25 fiscal year. The department says those activities account for about one-third of its annual budget, making it important to determine which stocking efforts produce lasting results.
Jen Johnson, a senior fisheries management biologist with the DNR, explained the concept during a Wednesday meeting of the Michigan Natural Resources Commission in Marquette.
“Think about genetics (testing) like Ancestry.com, 23andMe,” Johnson said. “Are you related? That’s the big question that we’re asking here.”
The technique, known as parentage-based tracking, allows researchers to examine the genetic relationships between fish in a lake and the parent fish used in stocking operations. By determining whether fish in a particular body of water descend from those parents, biologists can better assess whether stocked fish are surviving and reproducing.
Previously, the department’s methods for measuring stocking success were limited or expensive, according to the DNR. The genetic approach has proved cost-effective during pilot research and has reduced the amount of staff time needed to track results.
The findings also suggest stocking does not produce the same results everywhere. The Upper Peninsula pilot program found evidence that stocking was working in some lakes but not others, information that could help fisheries managers evaluate where their efforts are most effective.
Randy Claramunt, the DNR’s fisheries chief, said the new method could provide a much deeper understanding of the department’s work.
“This tool is going to open up a lot of insights into what we do at the fish division,” Claramunt said.
The department’s goal is to use the genetic information to make better-informed decisions about fish stocking and determine whether its investments are producing sustainable results. Rather than relying only on traditional tracking methods, biologists can use parentage testing to establish whether stocked fish are contributing genetically to populations in the lakes where they are released.
The Michigan Department of Natural Resources’ program was reported by Bridge Michigan in an article by Laura Herberg.
