Safeguarding islands: A systematic review of global island biosecurity plans

Islands are globally recognised for their unique biodiversity and high levels of endemism. These fragile ecosystems also support the livelihoods of hundreds of millions of people, many of whom depend directly on natural resources for economic and cultural wellbeing. As international and domestic trade and tourism increases globally, so too does the risk of introduction of invasive alien species. In response, a growing number of islands have developed biosecurity plans to manage these risks. This study presents a systematic review of global island biosecurity plans. We found 41 island biosecurity plans from 13 countries with three countries accounting for 63 % of all island biosecurity plans; Australia (15 of 41 biosecurity management plans; 37 %), United States of America (6 of 41; 15 %), and New Zealand (5 of 41; 12 %). The number of world heritage sites, and the volume of international tourist arrivals, emerged as strong predictors for the presence of an island biosecurity plan. However, these factors were not strong predictors of the contents of plans. Plan content was strongly associated with interactions between environmental (e.g. terrestrial, marine, freshwater, or disease), governance (e.g. site, local, subnational, national, regional, or international), and economic (e.g. agriculture, fishery, tourism, export, import, or other) focus of islands. By highlighting the limited number of islands globally with established biosecurity management plans, and identifying shared features and context-dependent differences, this study provides a foundation for developing generalised, yet adaptable, biosecurity frameworks tailored for diverse island contexts