MINNEAPOLIS (WCCO) – The Minnesota Department of Natural Resources is encouraging anglers to toss back large sunfish and only keep the small ones to fry.

The DNR says that large sunfish, males in particular, play an important role in creating conditions where sunfish can grow to “keeper” size. So, in order for more large sunfish to grow, anglers are being asked to throw the big guys back.

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Wait, how does this work?

According to the DNR, the removal of large sunfish from lakes creates an environment where the small males don’t need to grow to compete for the best spawning areas, which are guarded during the spring and summer by the big guys.

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Instead, when the small males discover there’s no big sunfish, they switch their focus from bulking up to spawning, resulting in the lake becoming filled with small sunfish.

The DNR says that Minnesota anglers harvest around 16 million sunfish each year, making them the state’s most harvested fish.

Additionally, decades of survey data on anglers’ attitudes on sunfish show that they are generally OK with the amount of sunfish they catch on Minnesota lakes, but not so happy with the size of fish.

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“To maintain a high quality fishery, it’s important that anglers, guides and resort owners, all understand the important role these large nesting fish play, and that we all work together to exercise a conservation ethic that ensures these fish thrive,” said Grand Rapids area fisheries supervisor Dave Weitzel, in a press release.