Risk Assessment of Non-Native Nile Tilapia (Oreochromis niloticus L.) in Iran

The present study was carried out to assess the risk of non-native Nile tilapia (Oreochromis niloticus L.) in Iran. The common invasive risk assessment protocols of non-native species were examined according to specific criteria, and the invasive risk assessment of this species was applied based on the selected method and auxiliary tools of species distribution models. The Aquatic Species Invasiveness Screening Kit (AS-ISK) received the highest score for assessing the invasive risk of non-native fishes in the freshwaters of Iran. The results showed that the risk of the species in Iran is high, and its impacts are significant. The mean scores of the Basic Risk Assessment (BRA) and the total risk assessment (BRA+Climate Change Assessment) were obtained as 41.5 and 53.5, respectively, which are much higher than the threshold values of the model for Iran (i.e., 21). Also, according to the results of other protocols used, the species has a high risk. Overall, the Nile tilapia possess a high potential invasive risk in the country, and unfortunately, its control is complicated, costly and mostly impossible in the recipient ecosystems. Therefore, as the best management measure, preventing the introduction of this species should be considered.