Non-native marine species risk screening and vector analysis to inform conservation management in the southern Caribbean

Marine protected areas of the Caribbean islands are at high risk of non-native species (NNS) introductions and impacts that may threaten conservation goals. To inform conservation management of these protected areas, the present study identified potentially-invasive NNS as well as introduction vectors and pathways for the southern Caribbean islands of Grenada, and St Vincent and the Grenadines. The activities associated with the introduction vectors and pathways relevant to priority NNS were assessed to highlight locations within the risk assessment area at elevated risk of NNS introduction and spread. The preliminary NNS list comprised 223 species of which 10 were screened using the Aquatic Species Invasiveness Screening Kit, which generated scores indicating moderate-to-high risk (18–51) of being invasive in the risk assessment area, based on generalized global threshold scores. The ports of Kingston (St Vincent) and St George’s (Grenada) were associated with the greatest shipping and boating activity, indicating elevated risk of NNS introductions by way of these vectors. Coastal areas in the south of the risk assessment area were associated with highest risk of introduction of NNS by natural dispersal. The evidence presented in this study provides a strong basis upon which to develop and implement risk-based biosecurity and monitoring programmes to protect and conserve this region’s marine protected areas.