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IUCN Red List of Threatened Species


The World Conservation Union, through its Species Survival Commission (SSC) has for over 40 years been assessing the conservation status of species, subspecies, varieties and even selected subpopulations on a global scale in order to highlight wildlife threatened with extinction, and therefore promote their conservation. The IUCN Red List of Threatened Species provides taxonomic, conservation status and distribution information on wildlife that have been evaluated using the IUCN Red List Categories and Criteria.

This system is designed to determine the relative risk of extinction, and the main purpose of the IUCN Red List is to catalogue and highlight wildlife that are facing a higher risk of global extinction (i.e. those listed as Critically Endangered, Endangered and Vulnerable). The IUCN Red List also includes information on wildlife that are categorized as Extinct or Extinct in the Wild; on wildlife that cannot be evaluated because of insufficient information (i.e. are Data Deficient); and on wildlife that are either close to meeting the threatened thresholds or that would be threatened were it not for an ongoing taxon-specific conservation programme (i.e. Near Threatened).

A summary of the data for 2004 is given in the table below. For more detailed and up-to-date information can be found at:

Numbers of threatened species by major groups of organisms (19962004) <Click image for larger view>

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