One of the global indicators for invasive alien species is the Red List Index for impacts of invasive alien species.
The Red List Index (RLI) for impacts of invasive alien species shows the overall impact of invasive alien species (IAS) on the extinction risk of species globally. It is a measure of how fast IAS are driving the world’s biodiversity to extinction (and how effectively we are mitigating this). It shows changes over time in the extinction risk of all bird, mammal and amphibian species worldwide driven by IAS, integrating the negative impacts of invasions and the positive impacts of successful eradication and control programmes for IAS. The number of species in each Red List category and the number changing categories between assessments as a result of genuine improvement or deterioration in status is assessed (see Butchart et al. 2004, 2005, 2007 for further detail) and for each genuine category change, the primary driver (threat, or threat mitigated) is identified. The extent to which IAS are primary drivers of category changes for threatened birds, mammals and amphibians is then determined.
Further information about the Red List Index.