A Global Account of Established Non-Native Fish Species

Area of Science:

• Ecology
• Invasive Species Biology
• Conservation Science

Background:

• Non-native aquatic species introductions, driven by human activities like aquaculture and trade, significantly alter ecosystems.
• Despite concerns, a comprehensive global assessment of established non-native fishes and their impacts is lacking.

Purpose of the Study:

• To conduct a global appraisal of established non-native fish species.
• To analyze their taxonomic diversity, geographic spread, introduction routes, and ecological consequences.
• To identify knowledge gaps regarding invasion impacts.

Main Methods:

• Compiled a global dataset of established non-native fish species from multiple sources.
• Included 1535 species across 193 countries, covering 82% of global coverage.
• Analyzed introduction pathways and documented ecological impacts.

Main Results:

• Leuciscidae, Cichlidae, Salmonidae, and Cyprinidae are the most common families. Introduction rates appear to be declining.
• Aquarium trade and aquaculture dominate freshwater introductions, while corridors are key for marine species.
• Impact data is limited, but competition and predation are primary threats to native biodiversity.

Conclusions:

• Significant knowledge gaps exist regarding the ecological impacts of non-native fish.
• Urgent policy and management interventions are crucial for high-risk invasions.
• This study provides a foundation for targeted biosecurity policies to mitigate invasion impacts.