Climate change scenarios differentially modulate the impact of invasion in a native macrophyte species

Biological invasion and climate change threaten freshwater ecosystems, potentially amplifying their impacts through interaction. However, empirical evidence on how future climate scenarios influence the invasion process and their interactive effects on native species remains limited. We conducted a full‐factorial experiment to evaluate the independent and interactive effects of Hydrilla verticillata invasion and future climate scenarios (baseline, mitigation, and business‐as‐usual) on the native macrophyte Cabomba caroliniana. We also assessed the response of the non‐native H. verticillata to these climate scenarios. The climate change mitigation scenario maintained the invasive potential of H. verticillata, as indicated by its vertical growth and colonization potential via vegetative propagules, which were comparable to baseline conditions. Simultaneously, the mitigation scenario supported the vertical growth and production of C. caroliniana at levels similar to those under the baseline. Under the business‐as‐usual scenario, H. verticillata exhibited enhanced vertical growth and colonization capacity via vegetative propagules. Interestingly, its presence under the business‐as‐usual scenario was associated with increased vertical production of the native species. Although invasion appeared to buffer the adverse effects of extreme climatic stress, it merely enabled C. caroliniana to recover vertical production to baseline and mitigation levels, rather than providing a long‐term advantage. Our findings highlight the ecological benefits of climate change mitigation and the complex outcomes arising from the interaction between invasion and future climate scenarios for native species.