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Home - Species - Concepts - Categories of risk in the world

In order to be more objective, the definitions currently used by the IUCN are necesarily complex. Some of the conditions necessary for classification in the different categories are given below:


When there is no reasonable doubt that the last individual of a species has died.


When individuals of a species survive only in captivity or in populations outwith their historical range.


When a species faces a high risk of extinction in the wild due to:


When a species faces a high risk of extinction in the wild due to:

Their population being less than 250 mature individuals, even if stable.




When a species has been evaluated under the criteria and, while not qualifying for the high risk categories, is very close and will probably qualify in the future.


When existing information is inadequate to assess risk of extinction of a species.


When a species has been assessed against the criteria but does not qualify for the high risk categories and would probably not qualify in the near future as it is abundant and has a wide distribution range.
 
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