Invasive species as threat multipliers in freshwater ecosystems: biodiversity loss, interacting stressors, and management responses in the Anthropocene

Résumé

Freshwater ecosystems occupy a small proportion of the Earth’s surface yet support exceptionally high biodiversity and essential ecosystem services. In the Anthropocene, these systems are increasingly threatened by interacting pressures, including hydrological alteration, land-use change, pollution, climate warming, and biological invasions. This review examines invasive species as a major driver of freshwater biodiversity loss between 2015 and 2026, while situating invasions within the broader multi-stressor context emphasized in recent freshwater studies. Importantly, this review advances the concept of invasive species as “threat multipliers” , defined here as ecological agents that not only exert direct impacts but also amplify, reinforce, and prolong the effects of co-occurring stressors such as climate change, eutrophication, and hydrological disruption. This framing extends beyond traditional invasion ecology by explicitly linking invasion processes to multi-stressor interaction theory. Evidence shows that invasive fishes, macrophytes, decapods, and other ecosystem engineers reduce native biodiversity through competition, predation, habitat modification, food-web disruption, pathogen transfer, and biotic homogenization. Their impacts are often intensified by warming, nutrient enrichment, altered flow regimes, and other disturbances that facilitate establishment, spread, and ecological dominance. Where available, quantitative evidence demonstrates substantial ecological and socio-economic consequences, including reductions in biodiversity indices, declines in ecosystem functioning, and measurable economic losses associated with degraded ecosystem services. In addition, invasions impair ecosystem functioning and weaken ecosystem services by altering water clarity, nutrient cycling, habitat structure, fisheries productivity, and biomonitoring reliability. The review also highlights emerging responses, including eDNA-based early detection, prioritization frameworks, integrated control strategies, and the concept of functional eradication where complete removal is unrealistic. Major knowledge gaps remain in understanding multi-invader interactions, seasonal detectability, cross-ecosystem spillovers, long-term ecological change, and climate-ready management, especially in underrepresented regions such as Africa. This review provides both generalizable insights and region-specific implications for biodiversity conservation and management in the Anthropocene.

Citer ce document

Accès au document

Texte intégral en lecture en ligne, réservé aux abonnés SPHAERO et aux membres de l'institution. Se connecter

Auteur(s)

Statistiques

Consultations : 1

Téléchargements : 0