EFFECTS OF INVASIVE FISH SPECIES ON NATIVE SPECIES AND AQUATIC ECOSYSTEMS

Abstract

Biological invasions have emerged as one of the major drivers of global biodiversity loss, threatening native species, ecosystem functioning, and human well-being. This review examines the impacts of invasive species on native fish species and aquatic ecosystems, with emphasis on mechanisms of invasion, pathways of introduction, ecological consequences, and management strategies. Deliberate and accidental introductions facilitated by globalization, aquaculture, trade, and transportation have accelerated the spread of invasive organisms across freshwater and marine environments. Invasive fish species such as Nile perch (Lates niloticus), common carp (Cyprinus carpio), and other non-native organisms alter trophic interactions, compete with indigenous species, transmit diseases, and disrupt ecosystem processes, leading to biodiversity decline and reduced fisheries productivity. Ecosystem-level impacts include alterations in food webs, nutrient cycling, habitat structure, and ecosystem services, with significant socioeconomic consequences for fisheries and aquatic resource-dependent communities. The review further highlighted prevention, early detection, mechanical, chemical, biological, and emerging technological approaches for invasive species management, emphasizing the importance of integrated and pathway-based control strategies. Effective management requires coordinated international policies, strengthened biosecurity measures, and ecosystem-based approaches to safeguard native biodiversity and ensure the sustainable utilization of aquatic resources. Continued research, monitoring, and stakeholder collaboration are essential to mitigate the increasing threats posed by invasive species in a rapidly changing world.