The categories in the middle, i.e., “vulnerable” and “endangered,” are for species considered under threat.
The IUCN Red List has nine categories to indicate how close a species is to becoming extinct. The closest to extinction is the “critically endangered” category, with a species example being the Asiatic cheetah (Acinonyx jubatus venaticus), a subspecies found only in Iran that has dwindled to fewer than 50 animals remaining in the wild. The least critical category is defined as “least concern.” For example, the global brown bear (Ursus arctos) population is considered to be of “least concern” because it is large and spread over three continents, even though there are some local populations that are under threat. The categories in the middle, i.e., “vulnerable” and “endangered,” are for species considered under threat.