What are the categories of endangered animals?

The International Union for Conservation of Nature (IUCN) defines seven categories of threatened species:

1. Extinct (EX): No known individuals of the species remain alive.

2. Extinct in the Wild (EW): The species survives only in captivity, with no populations remaining in their natural habitats.

3. Critically Endangered (CR): The species面临极高的灭绝风险，全球范围内存在数量极少或生存范围极其狭窄的种群。

4. Endangered (EN): The species面临极高的灭绝风险，但比极度濒危的物种种群数量略多或分布范围略广。

5. Vulnerable (VU): The species面临较高的灭绝风险，但比濒危物种数量略多或分布范围略广。

6. Near Threatened (NT): The species is close to being considered vulnerable, but does not meet the criteria for any of the other threatened categories.

7. Least Concern (LC): The species is widespread and abundant, with a low risk of extinction.