Carpobrotus edulis, a highly invasive plant species repeatedly introduced along the Atlantic coast of South America, poses a significant threat to the ecological integrity of coastal dune ecosystems in Uruguay. This study used 15 years of iNaturalist records to assess the magnitude of Carpobrotus invasion, focusing on its distribution, abundance, and reproductive phenology. Through the analysis of georeferenced and dated data, we determined that Carpobrotus has spread extensively, covering a 10-km-wide coastal area and occupying approximately 220 km along the Atlantic coast and the outer Rio de la Plata estuary. Records have increased in the last three years, with a summer prevalence of 52.9%, due to higher activity on the platform. The species exhibited two flowering peaks in spring and autumn, suggesting an extended reproductive period. The widespread presence of this species in both natural and urbanized areas highlights the urgent need for effective management strategies to mitigate its impact on native biodiversity. Utilizing citizen science platforms like iNaturalist has been instrumental in monitoring and documenting processes of invasion. However, further investigations are necessary, particularly in less sampled regions, to fully understand the extent of Carpobrotus invasion. To protect the country’s coastal ecosystems, it is crucial for local authorities to reassess current practices related to non-native species ornamental planting. By addressing the invasion of C. edulis, the ecological integrity of coastal dune ecosystems can be preserved, ensuring the survival of native flora and fauna along Uruguay’s Atlantic coast.