Worldwide invasions of Centrarchidae: The dark side of the sunfish family.

Abstract

Freshwater fish invasions are major drivers of global ecological change, disrupting native biodiversity and ecosystem functions. However, many invasive fish hold significant socioeconomic value, resulting in conflict over their management. Centrarchidae, which are globally distributed and are important for sportfishing and aquaculture, are now potentially becoming a global threat. Yet, no comprehensive appraisal exists across taxa and regions integrating taxonomy, pathways, impacts, and risk analysis for Centrarchidae. To address these gaps, we compiled published literature and leveraged publicly available databases to critically evaluate the current global status of non native Centrarchidae, finding 30 species established outside their native ranges with 17 being outside of North America. Largemouth bass (Micropterus nigricans) and pumpkinseed (Lepomis gibbosus) are the most widely 108 introduced centrarchids. Reported impacts of Centrarchidae introduction are mostly ecological, with predation, competition, hybridization and disease transmission as major mechanisms. Conversely, socio-economic and cultural effects are underreported. Currently, only ten species have undergone rapid risk screening, with 90% flagged as high risk. However, risk analyses remain sparse, confounded by taxonomic uncertainties (including hybridization) and context dependence of impacts. With the changing climate and other anthropogenic disturbances in freshwaters, habitat suitability is expanding for centrarchids. Although concerning, Centrarchidae form a highly human-mediated invasion complex with predictable pathways and tractable leverage points, so limiting propagule pressure and standardizing assessments can curb their future spread while informing balanced and evidence-based fisheries policy that reconcile socioeconomic benefits with environmental costs.