Bringing together cutting-edge data science techniques in the Artificial Intelligence (AI) domain and the wealth of information available on the internet can improve ecological conservation and support a sustainable exploitation of natural resources. In this work we demonstrate the potential of citizen science online platforms and their broad image collection to track the spread of a recently detected invasive alien gastropod species within and beyond the currently known invaded range. For that, computer vision tools were used to train a supervised machine learning model for early detection and spread of this inconspicuous invasive alien species and applied it to screen for unreported individuals. Our validation case is a recent invader in Europe, currently reported only in Spanish and Portuguese coasts, with recognised negative impacts both on native biodiversity and shellfish commercial exploitations.