How to read the IUCN Red List
A Red List category is a dated extinction-risk assessment of a named taxon in a stated geographic scope, supported by criteria and an assessment record.
Scope: Global and IUCN-published regional species assessments; not a substitute for national legal-protection lists · Last updated
Begin with identity, scope, and date
Confirm that the assessment covers the taxon you mean, including any subspecies or population qualifier. The summary states whether the scope is global or regional and gives the last assessment date. It can also report population trend, habitats, threats, conservation actions, and a distribution map; missing fields should not be silently filled with assumptions. [1][3]
Read the category ladder precisely
The sequence includes Extinct, Extinct in the Wild, Critically Endangered, Endangered, Vulnerable, Near Threatened, Least Concern, and Data Deficient. Only the middle three are collectively called threatened by IUCN. Not Evaluated taxa do not appear as assessed species on the Red List, and Data Deficient is not positioned as a low-risk category. [1][2]
Open the criteria and rationale
Categories are assigned through quantitative criteria concerning population reduction, geographic range, small population size and decline, very small or restricted populations, or quantitative extinction analysis. The assessment text explains the evidence and criterion used. A badge without that rationale leaves out the assumptions, time windows, and uncertainty behind the result. [2][3][6]
Treat status as a dated assessment
A global result and a regional result can differ because they cover different populations, use different dates, or apply regional rules. A later category change may reflect a genuine biological change, but it can also follow new information, taxonomic revision, corrected error, or changed methods. Cite the assessment itself and its date rather than copying an undated category from another page. [3][4][5]
Related guides
Identify it and save the field note.
Where this guide comes from
Source-checked editorial guide. Last updated . This guide teaches identification and field skills; it is not a substitute for expert verification when it matters.
