The first national assessment of established non-native species in Türkiye

The ecological and socio-economic impacts of non-native species underscore the importance of maintaining accurate national lists to support biosecurity and management strategies. Türkiye’s most recent national list highlights ongoing challenges in keeping records up-to-date. To advance Türkiye’s national assessment of non-native species, we present the first comprehensive list of established non-native species, documenting 271 species from 160 families across diverse taxonomic groups. Marine species ( n = 198) dominated the list, with notable contributions from Chordata, Mollusca, and Arthropoda, followed by Terrestrial (42), Freshwater (27), Terrestrial/Freshwater (3) and Freshwater/Marine (1). Our spatial analysis revealed considerable regional variation in data availability, with urban and coastal areas exhibiting higher rates of species establishment, likely facilitated by human-mediated pathways. We also identify Türkiye’s role as a crucial hub for the spread of non-native species across country borders. Furthermore, we demonstrate that 17% of non-native species have known ecological or economic impacts, emphasizing the need for targeted impact assessments, monitoring, and proactive management. By providing a detailed and up-to-date inventory of established non-native species and their impacts, this study offers a critical foundation for strengthening biosecurity policies, guiding targeted monitoring efforts, and fostering coordinated management responses at local, national, and international scales to safeguard Türkiye’s biodiversity.