Assessing the impact of an invasive plant in a Protected Natural Area: Island of Cozumel, Mexico

The Island of Cozumel, located in the Mexican Caribbean, has been granted several protection denominations because of its high biodiversity. However, despite these efforts, several invasive species have been found on the island. Of these, published studies indicate that two plant species are invasive in beach and coastal dune vegetation, but information on their impact on native plant communities is lacking. This study aimed to analyze the impact that the invasive shrub, Scaevola taccada, has had on plant species composition, richness, diversity, and community structure of beach and coastal dune vegetation developing on the Island Cozumel. Our results suggest significant impacts on species composition: we observed 34% species turnover between invaded and non-invaded plots. Invaded plots also showed a decreased plant cover and changes in species dominance resulting in altered community structure. S. taccada has rarely been studied in Mexico, especially its invasiveness and impact on plant communities. Our results highlight the urgent need for programs to monitor and control the spread of this species throughout the coasts of the Island of Cozumel. Ultimately, the information reported here will be helpful to inform management actions regarding the need to control invasive species in this Biosphere Reserve.