ABSTRACT
A strong, efficient, and effective biosecurity system requires the determination of which areas are most susceptible to threat incursion, establishment, and spread. Maps of establishment potential are developed to inform where surveillance resources should be focused, to assess likely spread scenarios, estimate likelihoods of threat absence, create risk maps for prioritising threats and optimally minimise risk. This chapter outlines the three fundamental geographic barriers that influence establishment potential—propagule pressure, abiotic suitability, and biotic suitability. We describe how each barrier is commonly approximated using a range of methods such as species distribution models, pathway analyses, expert elicitation, border screening data, and distributional data of host or habitat. We provide particular emphasis on the various decisions and assumptions that must be made when constructing species distribution models for invasive species. Lastly, we provide a practical and pragmatic approach for integrating these various models and data to create maps of establishment potential. We illustrate this integrated approach using a hypothetical case study on oriental fruit fly (Bactrocera dorsalis) entering Australia.
