Central Wisconsin News

University of Wisconsin-Stevens Point graduate student Ryan Bohen is bringing attention to a native fish species in Wisconsin, leading research that could influence fisheries management across the state.

Bohen, from UW-Stevens Point’s College of Natural Resources, is examining the population dynamics of bigmouth and smallmouth buffalo. These native fish species often go unnoticed in traditional fisheries management. Despite their longevity—some live up to 70 years—and ecological importance, they have seldom been the focus of scientific study.

Bohen's research aims to shift understanding of buffalo populations by studying age structure, reproductive patterns, and growth in 14 waterbodies across Wisconsin. The study also examines the role of buffalo in bowfishing tournaments statewide.

“Bigmouth and smallmouth buffalo are lesser-known native species that have garnered more attention in recent years due to their capacity to live to old ages,” said Bohen. “Our goal is to gather the data needed to make informed decisions about managing these populations, especially as bowfishing becomes more popular.”

Bowfishing involves shooting fish with a bow and arrow, often at night. Buffalo contributed moderately to tournament harvests in 2023 and 2024, representing about 17% of total harvest over two years.

To assess buffalo resiliency against harvest pressure, Bohen's team used advanced techniques to estimate fish age, finding lifespans ranging from 14 to 71 years. They also noted significant variation in how quickly buffalo reach reproductive maturity; some mature within two years while others take more than six.

“These findings show how adaptable buffalo are, but they also highlight the need for careful management,” said Daniel Isermann, director of the U.S. Geological Survey’s Wisconsin Cooperative Fishery Research Unit and Bohen’s advisor. “Not all populations will respond the same way to harvest pressure.”

The research was conducted with the Wisconsin Department of Natural Resources and the Wisconsin Bowfishing Association. It marks the state's first formal assessment of bowfishing harvests statewide and provides crucial data for future regulations and conservation strategies.

For Bohen, this project goes beyond academia. It offers a chance to raise awareness about an understudied species and contribute to long-term sustainability efforts for Wisconsin’s aquatic ecosystems.

“It’s exciting to conduct novel research on an understudied native fish,” he said. “Non-game native species like buffalo have historically received little management attention, but their role in aquatic ecosystems is just as important as that of native sportfish.”

Bohen’s findings may inform monitoring and management practices for other non-game fish species.

“Research like this is essential for making informed decisions,” Bohen said. “It’s exciting to be part of something that could actually affect management on the landscape.” He will graduate in January after presenting his results at his graduate public seminar in December.