Climate-driven distribution shifts of invasive earthworm species in a river basin affected by mining tailings

Changes in temperature and precipitation patterns, along with extreme weather events, have altered natural habitats, contributing to species extinctions and ecosystem fragmentation worldwide. Climate change can exacerbate disturbances and trigger biological invasions that threaten native species. Here, we used ecological niche models to predict the future distribution of five invasive earthworm species (Amynthas corticis, Amynthas gracilis, Dichogaster bolaui, Polypheretima elongata, and Pontoscolex corethrurus) within the Doce River Basin (DRB), Brazil. We also assessed the potential contribution of the Fundão dam collapse to changes in species distributions by using a vegetation index as a proxy for forest cover. We found that, despite being invasive, most species are expected to experience contractions in climate suitable areas, with losses reaching up to 30.2% for P. elongata. Only D. bolaui is predicted to find climate suitable areas across the entire study area in all climate scenarios. The results also indicated that the Fundão collapse may contribute to greater reductions in the average climate suitable area within forested areas, with post-collapse areas approximately 44% smaller than pre-collapse conditions. Nevertheless, the southwestern portion of the DRB is projected to retain suitable climate conditions for all species, indicating a high invasive potential in this region. These findings highlight the need for targeted management strategies to prevent the dominance of invasive species and restore vegetation to buffer against the impacts of climate change and control invasive earthworms. Ecological restoration efforts, alongside the integration of environmental monitoring and ecological modeling, are crucial for mitigating biodiversity loss and enhancing ecosystem resilience to invasion by alien earthworms in the face of climate change.