Minnesota DNR Reports State’s Perch Are Shrinking in Size and Number

by Shelby Scott
(Photo by Reinhard Dirscherl/ullstein bild via Getty Images)

This fall, Minnesota anglers are facing a strange issue. Many of them have noticed that the state’s perch population is suddenly shrinking, both in size and in number. More on the new mystery and ongoing DNR investigation below.

According to the above clip from KARE 11, the state’s Department of Natural Resources (DNR) has begun investigating the problem. Everyday Minnesotans got an up-close, birds-eye view of the state’s perch and other popular fish populations at the DNR fish pond during the state fair earlier this month.

The outlet, speaking with local anglers, got insight into the state’s fish aside from investigating the shrinking population.

“They’re really good to eat,” one fairgoer said of the perch. “You just have to find fish that are big enough to fillet and get decent-sized filets.”

Sadly, however, these large-enough fish are rapidly disappearing. Speaking about MN’s perch problem, DNR rep Beth Holbrook stressed, “I think it could potentially be a problem particularly in our lakes that we really love to fish.”

What’s Causing the Perch to Shrink?

She continued, “Our conclusion is that perch bigger than five inches are decreasing in numbers and that those perch aren’t reaching a maximum size as big as they used to in the past.”

But what lies at the center of the problem? Holbrook believes the usual suspect is global warming. Specifically, she believes climate-warmed water, a change in perch predators, and zebra mussels have contributed to the early maturation of perch, therefore resulting in a smaller version of the species overall.

In a way, the zebra mussels work in the predators’ favor as they eat away at the lakes’ murkiness and overall nutrients, enabling predators to better see schools of perch. The DNR plans to continue its study into the shrinking fish population over the next year.

Minnesota Recently Experienced Another Strange Fish Mystery

Aside from the state’s holistically shrinking perch population, MN recently saw itself navigating another, more lethal, fishing mystery.

Over the summer, authorities became involved in an investigation after more than 2,500 fish—mostly brown trout—turned up dead. While there was no immediate answer to the cause, both authorities and local anglers at the time believe the mass deaths were caused by fertilizer runoff from nearby farms.

Wildlife experts and fishermen alike laid blame on local farms as a similar incident happened back in July. Severe storms rolled through the Midwestern state at the end of the month and, not long after, mass amounts of fish were found dead.

Following the most recent fish kill, Minnesota Pollution Control Agency (MPCA) spokesperson Mike Rafferty said, “Field crews from the three agencies have collected fish and water samples and are analyzing results to help determine the cause.”

As unbelievable as these mass fish kills seem, they’re hardly uncommon. Reports state as many as 500 mass kills like this take place every year. That being said, they’re more commonly a result of natural causes.