The conservation status of a species indicates the likelihood that it will become extinct. Many factors are considered when assessing the conservation status of a species; e.g., such statistics as the number remaining, the overall increase or decrease in the population over time, breeding success rates, or known threats.[2] The IUCN Red List of Threatened Species is the best-known worldwide conservation status listing and ranking system.[3]
Over 40% of species are estimated to be at risk extinction.[4] Internationally, 199 countries have signed an accord to create Biodiversity Action Plans that will protect endangered and other threatened species. In the United States this plan is usually called a species Recovery Plan.