The Gulf toadfish goes south: assessing the potential habitat suitability of Opsanus beta in response to climate change

Climate change can directly influence invasive species range, and may reflect in greater habitat suitability, consequently increasing losses in native biodiversity. Habitat suitability modelling can help identify priority areas for conservation and rapid response for invasive taxa. This study aimed to model the habitat suitability of Opsanus beta, an invasive fish species, in South America under current and future climate change scenarios. Three modelling techniques, Generalized Linear Model (GLM), Maximum Entropy Algorithm (Maxent), and Random Forest (RF), were applied, and their results were compared and then put together in an Ensemble model to visualize habitat suitability. We found that the current habitat suitability of O. beta in South America is relatively low, with its occurrences mostly related to coastal port areas, suggesting that the species was introduced from ballast water. The increase in mean temperature at mean depth and temperature range were the most relevant variables influencing the species habitat suitability. The gradual increase in habitat suitability for the 2100 climate change scenarios, particularly in more severe climate change scenarios, such as the RCP 8.5, was also observed. The study highlights the critical need to use habitat suitability models to mitigate the impact of future climate change scenarios on invasive species. The findings call for preventive measures to be taken in time to prepare areas that may become the target of dispersal and establishment of O. beta.