The relationship between a global population, sub-population and local population for the purposes of EICAT assessments. The global population includes all individuals of a taxon, a sub-population is a geographically or otherwise distinct group in the population, and a local population is a group of individuals within a sub-population. In this example, local population 1 includes all individuals within sub-population 1. Local populations 2, 3 and 4 are connected by frequent natural immigration, whereas sub-populations 1 and 2 are largely isolated from each other. Reproduced from IUCN (2020a) IUCN EICAT Categories and Criteria, IUCN (Gland): page 4, https://doi.org/10.2305/IUCN.CH.2020.05.en, with permission from IUCN.

 
 
  Part of: Volery L, Blackburn TM, Bertolino S, Evans T, Genovesi P, Kumschick S, Roy HE, Smith KG, Bacher S (2020) Improving the Environmental Impact Classification for Alien Taxa (EICAT): a summary of revisions to the framework and guidelines. In: Wilson JR, Bacher S, Daehler CC, Groom QJ, Kumschick S, Lockwood JL, Robinson TB, Zengeya TA, Richardson DM. NeoBiota 62: 547-567. https://doi.org/10.3897/neobiota.62.52723