The IUCN Red List sorts species into nine categories, of which only three count as threatened

Background

The International Union for Conservation of Nature runs the IUCN Red List of Threatened Species, which it calls the most comprehensive information source on the global extinction risk status of animal, fungus and plant species. Species are classified into one of nine Red List Categories - Extinct, Extinct in the Wild, Critically Endangered, Endangered, Vulnerable, Near Threatened, Least Concern, Data Deficient and Not Evaluated. Only three of those nine are threatened categories: Vulnerable, Endangered and Critically Endangered species are considered to be threatened with extinction. Alongside the list IUCN publishes the Red List Index. The Red List Index shows trends in overall extinction risk for species, and governments use the Index to track their progress towards targets for reducing biodiversity loss. The Red List is made possible through the active participation of the 13 Red List Partner organisations. The Red List also includes the IUCN Green Status of Species, which assesses the recovery of species' populations and measures their conservation success; there are eight Green Status Categories: Extinct in the Wild, Critically Depleted, Largely Depleted, Moderately Depleted, Slightly Depleted, Fully Recovered, Non-Depleted and Indeterminate. The criteria in current use were published as 2001 IUCN Red List categories and criteria, version 3.1. IUCN is headquartered at Gland, Switzerland.