Restoration as a Pathway to Invasion: Early Management of Scaevola taccada in a Protected Restinga

Biological invasions are a leading direct driver of biodiversity loss in coastal ecosystems worldwide, undermining conservation investments and the effectiveness of protected areas. Here, we report the first occurrence and incipient invasion of the Indo-Pacific shrub Scaevola taccada in a legally protected coastal reserve in southeastern Brazil and quantify its early spread relative to the rare native congener S. plumieri . Using systematic shoreline transects and georeferenced mapping, we detected 12 shrubs of the exotic species and only a single large individual of the native species, and classified S. taccada as a dominant invader according to a widely used decision key for invasive plant management. Our results show how canopy opening associated with tree-invader removal can inadvertently create establishment opportunities for new invasive species, illustrating a general restoration–invasion trade-off that is relevant for coastal management far beyond Brazil. Building on global evidence for the cost-effectiveness of early detection and rapid response, we provide a practical identification key, a spatially explicit baseline for eradication, and management recommendations aligned with national guidelines for invasive plant control. This case demonstrates how integrating historical herbarium data, targeted surveys, and reserve staff participation can transform an isolated “first record” into a model for proactive management of emerging coastal invaders in protected areas worldwide.