The ICUN has many ranks that define an animal's population and risk of extinction.^[1] 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.^[2] They formerly used a identification called lower risk to describe some animals.

The ICUN defined an animal with the conservation status of lower risk is one with populations levels high enough to ensure its survival.^[3] Animals with this status did not qualify as being threatened or extinct. However, natural disasters or certain human activities would cause them to change to either of these classifications.^[4]

When it was in use, this classification was sub-divided into three types:

• Conservation dependent - where cessation of current conservation measures may result in it being classified at a higher risk level.
• Near threatened - may become vulnerable to endangerment in the near future but not meeting the criteria.
• Least concern - where neither of the two above apply.

• Biodiversity action plan
• Endangered species