The Fisherman as a Harvester of Nutrients
As freshwater fishers we have become efficient at catching them. It has become a passion for many taking a recreational activity to the level of a professional fisherman. As a commercial netter of fish, we also have become efficient in our pursuit that has been a profession since early man. Early man and now modern humans harvest fish by spearing. And then there is the profession of fish management where fish are caught and released to determine populations and limit the catch of the fishers in the name of preservation. It is a complicated affair but if one adds to it an ecological understanding of a place, fish management affects the nutrients in a body of water that supports the fish, they are managing one must look at the bigger picture.
In Northern Wisconsin and neighboring states over time fish management has reduced the catch by limited commercial fishing in favor of sports fishing. The number of commercial fishers has decreased in number but laws of traditional rights and “grandfather clauses” keeps them present in dwindling numbers. Over the past thirty years sports fishing regulations have already reduced the harvest of both game fish and panfish. We have the last thirty years reduced all game fish take by decreasing seasons of catch, increasing size limit, decreasing bag limit, and creating … as in walleye “protective slot limits” … that have not improved the fisheries. It has only created an angler culture of trophy fishing for all game fish species and taken away the food connection of eating fish that you catch … including both game and panfish. The amount of nutrients removed from our water bodies by fishers removing fish is now minimal.
Meanwhile, the nutrients entering and disturbances of even the once pristine Northwoods lakes continue to increase. Our fisheries and waters that support them in Wisconsin are in trouble. We may blame climate change, shoreline development, water quality, or all … but the answer is solving all is understanding and acting. We now have new tools of AI (artificial intelligence) to analyze fisheries and water resources data we have collected for the last one hundred years. We can manage our fisheries, so all fish grow well AND improve water quality. This is the importance in understanding nutrients in our aquatic ecosystems and channeling them up through the food chain and harvesting fish again.
Aquatic food chains have developed in the Northwoods from the time the Wisconsin Glacier retreated eighteen thousand years ago. The landscape we see today in the Northwoods is based on what this glacier deposited and the soils, plants, and animals that evolved making intricate webs of life that feed nutrients from the smallest of fish to the largest fish. This development created bacteria, plants, and animals that channel nutrient up the food chain in the cycles of seasons and years. We have large digital data banks describing physical, chemical, and biological characteristics of these organisms and their environments. We need to move to natural resource management that is in the restoration mode, paying close attention to what nature over this time has created.
The walleye, one of the most extensively researched fish in the Northwoods region of the Upper Midwest, serves as a valuable model for restoration efforts. This species thrives in rivers, lakes, and reservoirs, functioning as an effective predator throughout its lifespan while also serving as prey at various stages, including instances of cannibalism. Walleyes demonstrate a preference for cooler, darker aquatic environments, yet thrives in waters rich in nutrients as well in lakes with limited nutrients. It is adaptive in its history and what it needs nutrition-wise to flourish. It is cherished as food by humans today and even going back to glacier recession time.
We cherished this species so much we developed hatcheries to supplement our love for this species but instead altered both its genetics and ability to reproduce naturally while severely disrupting the food chain and habitat that supported its natural reproduction. This is the ideal species to use in the restoration process. It has a strong history of over one hundred years of fish management. Now let us use this history and accumulated knowledge to solve the problems we have created.
Walleyes, just as salmon, and many other species of fish (and even muskellunge), return to the place of origin … where the eggs were lain and fertilized. Walleye hatchery production in Wisconsin has failed to do this and now attempts in their fish and egg movement regulations to do better. A lake community organization can restore fish populations and restore the functioning of lake ecosystems to channel nutrients into the food chain again.
Walleye Restoration Foundation, Inc. has accepted this challenge. We have designed a small shoreline hatchery and created methods to increase walleye eggs, fry, and fingerling production. This is a beginning to restore natural reproduction production and good growth of all fish and address water quality decreases in lake and reservoir aquatic systems. We need lake partners to achieve this goal. Please visit our website for more information. Please contact us if you have any questions. Please contact us if you are interested in participating!
Rand Atkinson, President
September 26, 2025