Macrophyte Coverage Increases Largemouth Bass Abundance and Trophy Potential: A Resist‐Accept‐Direct (RAD) Application for Aquatic Plant Management in North‐Temperate Lakes

Climate change is altering north‐temperate lake ecosystems through warming and increased aquatic macrophyte production. These changes have the potential to cause ecosystem shifts that challenge status quo fisheries management and require the adoption of new strategies to resist, accept, or direct such shifts. Warming waters and increases in aquatic macrophyte production may benefit native warmwater fish species (e.g., bluegill Lepomis macrochirus , largemouth bass Micropterus nigricans ), while negatively affecting native cool‐ and coldwater species (e.g., yellow perch Perca flavscens , walleye Sander vitreus ) in north‐temperate lakes. Our objective was to test for relationships between largemouth bass electrofishing relative abundance (catch‐per‐unit‐effort, CPUE) and population size structure (proportional size distribution, PSD) and aquatic macrophyte coverage for 186 lake‐years during 2005–2018 (108 unique lakes) across northern Wisconsin lakes. Largemouth bass CPUE and PSD‐Memorable were significantly, positively related to aquatic macrophyte coverage. We found no relationship between largemouth bass PSD‐Stock, PSD‐Quality, or PSD‐Preferred and aquatic macrophyte coverage. Our findings suggest that managing aquatic macrophyte coverage may increase largemouth bass relative abundance, trophy potential, and recreational angling opportunity, especially in lakes that may be unable to continue to support cool‐ and coldwater fish populations. Our study provides a case for integrating the Resist‐Accept‐Direct (RAD) decision framework into aquatic macrophyte management.