Species-based prioritization is the most common and best-developed of the three focus areas, with many existing models . Species prioritization considers which alien species, and which traits, are associated with the greatest negative impacts on the economy, society, ecosystems, habitats, or native species.
This is a species-based and impact-focused scheme for assigning alien species to five semi-quantitative, sequential categories, ranging from minimal to massive impact [2,3].
Classification is based on a fixed set of mechanisms by which species cause impacts, including for example, competition or hybridization with native taxa, disease transmission and biofouling.
EICAT provides a transparent, standardized, and effective approach that can also be applied to a diverse range of taxa (across plants and animals) and differing types and quality of available evidence [2, 3].
Referenced material and links
McGeoch, M.A., Genovesi, P., Bellingham, P.J., Costello, M.J., McGrannachan, C. & Sheppard, A. 2016. Prioritizing species, pathways, and sites to achieve conservation targets for biological invasion. Biological Invasions 18, 299-314. doi 10.1007/s10530-015-1013-1
 Hawkins CL, Bacher S, Essl F et al (2015) Framework and guidelines for implementing the proposed IUCN Environmental Impact Classification for Alien Taxa (EICAT). Diversity and Distributions. Doi: 10.1111/ddi.12379