Madison Lakes: Perch Population Declines Due to Invasive Species

Madison, WI – The perch population in Madison’s lakes is facing a significant decline, impacting both the ecosystem and local businesses that rely on anglers. What was once a thriving fishery is now struggling, with catch rates plummeting to record lows, according to the Wisconsin Department of Natural Resources.

Pat Hasburgh, owner of D&S Bait Tackle and Fly Shop in Madison for the past four years, has witnessed the changes firsthand. A lifelong angler with 25 years of experience fishing Lakes Mendota and Monona, Hasburgh recalls a time when the lakes were renowned for their perch fishing.

“When I first started perch fishing here in town, 25 years ago, the perch population was crazy,” Hasburgh said. He remembers a bustling shop, often with lines stretching to the back, as anglers eagerly prepared for a day on the water. “I heard stories about lines all the way to the back of the shop, with people streaming in trying to get in on the good perch bite,” he recounted.

However, the situation has deteriorated steadily over time. “It’s just been on a slow decline, and this year is the worst we’ve ever seen,” Hasburgh stated. The decline in perch has directly affected his business, reducing customer traffic and altering inventory demands, particularly during the crucial winter months.

Data from the Wisconsin Department of Natural Resources confirms the anecdotal evidence. Catch rates have fallen dramatically, from 61 fish per net-night in 2020 to a record low of 14.4 fish per net-night in 2024. This sharp decrease raises concerns about the long-term health of the perch fishery and the broader ecological balance of the lakes.

Hasburgh points to the presence of zebra mussels and spiny water fleas as contributing factors to the decline. These invasive species disrupt the food chain, impacting the availability of sustenance for young perch. “I’ve definitely seen the perch population going down and now to the point where it’s very hard to even find catchable fish out there,” he explained.

Spiny water fleas, which became established in Lake Mendota in 2009, are a particular concern, as they are an invasive species of zooplankton that impacts the food supply for young perch, according to a report on Lake Mendota’s yellow perch population from 2020-2024.

Despite the challenges, Hasburgh remains optimistic about the possibility of a future recovery. While the current situation is dire, he hopes that ongoing monitoring and potential management strategies will help restore the perch population to its former abundance. The future of perch fishing in Madison, and the businesses that depend on it, hangs in the balance.