A version of this story was originally published on the USGS website on April 15, 2025.
Fishing plays a vital economic, cultural, recreational, and subsistence role in the United States. Annually, inland recreational fishing across the U.S. generates approximately $36 billion in expenditures. Midwestern states have some of the most valuable recreational fisheries in the country, with Minnesota, Michigan, and Ohio among the top six states for angling expenditures.
The Midwest is home to abundant lakes, rivers, and streams that support a variety of fish species including walleye, bass, catfish, trout, sturgeon, perch, sunfish, and others. Fishing activities contribute to local economies, tourism, and the overall well-being of communities across the region, connecting people with nature. Fishing is not only a recreational activity but also an important cultural tradition for many communities, including Tribes, where fishing is intertwined with cultural identity and tradition. However, fishing in the Midwest is facing a number of threats, including climate change, invasive species, and harvest pressure. The impacts of climate change are increasingly evident, affecting water temperature, fish habitat, and the timing of fish spawning. Warmer temperatures can lead to shifts in fish populations, altering species distributions and life cycles, which can affect the overall diversity of aquatic ecosystems. Changes in precipitation patterns also influence water quantity and quality, impacting fish habitats and reducing availability of those habitats during critical life history time periods (e.g., spawning and nursery habitats).
Managers and conservation organizations are actively working to address these issues through the implementation of sustainable fishing regulations, habitat restoration projects, reintroduction and stocking, and community engagement. If adaptation strategies—such as improving watershed management, restoring ecosystems, promoting climate-resilient fishing practices, and managing for future expected population shifts—are implemented, managers can be better prepared to manage for climate change, increasing and protecting the viability of fish populations and the livelihoods of communities that rely on freshwater fishing.
Supporting Fishing in the Midwest
The Climate Adaptation Science Centers (CASCs) are supporting state and Tribal natural resource managers as they seek to maintain and enhance opportunities for recreational and subsistence fishing opportunities in the Midwest. Results from multiple research efforts are providing information on habitat restoration practices that hold the greatest potential to enhance sportfish populations, expected shifts in fish communities as waters warm, and stocking strategies that will produce the best fishing opportunities.
Assessing Fisheries Across Landscapes in the Face of a Changing Climate
Fisheries managers are often confronted with the challenge of assessing thousands of waterbodies with limited staff and financial resources. The thousands of lakes and rivers in the Midwest vary in depth and shape, sensitivity to climate change, and current fish communities. Often, disparate and missing data limit the ability of managers to understand and respond to environmental change.
To address this challenge, CASC scientists are building models to determine if commonly measured indicators of fish population status can serve as simpler alternatives to more complex data-gathering methods. Partnering with state and Tribal fisheries managers, the project aims to address a critical need in inland fisheries management – how to best assess and manage data-limited fisheries, when information and resources are limited. The results will identify effective metrics that can aid managers in making more efficient and informed decisions about fish populations and their resilience in the face of climate change.
Learn more about this project.
Supplementing Sportfish Populations Through Stocking
Stocking fish raised in hatcheries and releasing them into bodies of water is a common practice used to support fisheries, especially when natural reproduction is low. As climate change threatens fish species that rely on cooler waters, like walleye, the demand for stocking these species is expected to increase as natural populations decline. However, fish available for stocking are a limited resource, and future stocking demand could surpass the available supply.
Focusing on walleye, CASC scientists worked with state agencies across the Midwest to analyze the future supply-and-demand tradeoffs associated with stocking, by forecasting the success of stocking efforts for individual lakes and reservoirs based on future climate projections. The results are helping state agencies understand how many walleye may be needed for future stocking efforts in order to maintain fishing opportunities, and the likelihood of success of these efforts. This information is helping managers ensure that stocking efforts are applied in the most cost-effective manner.
Learn more about this project.
Informing Climate-smart Fisheries Restoration and Management
Freshwater fisheries have faced challenges from habitat loss, pollution, overfishing, and species introductions for many years, and climate change compounds these challenges. Walleye, an essential cool-water sportfish, have been declining in the Upper Great Lakes Region since the early 2000s, although some populations have been thriving and even responding positively to warming temperatures.
Rather than solely focusing on the decline, CASC scientists are investigating the factors that contribute to successful walleye fisheries, highlighting effective management strategies in the context of environmental change. By collaborating with state and Tribal biologists, the team seeks to uncover insights that will support sustainable walleye management in a changing climate.
Learn more about this project.