IUCN Red List

The IUCN Red List of Threatened Species is the global standard for assessing extinction risk. It assigns each species to one of nine categories: Extinct (EX), Extinct in the Wild (EW), Critically Endangered (CR), Endangered (EN), Vulnerable (VU), Near Threatened (NT), Least Concern (LC), Data Deficient (DD), and Not Evaluated (NE). The three threatened categories are CR, EN, and VU, assigned against quantitative criteria on population size, decline rate, and range under Version 3.1. Red List status drives CITES listing proposals, CMS appendices, marine protected area prioritization, and bycatch and fisheries management for species such as vaquita and the right whale.