Extinct in the wild
A species that is extinct in the wild (EW) is one that has been categorized by the International Union for Conservation of Nature as known only by living members kept in captivity or as a naturalized population outside its historic range due to massive habitat loss.
Comparison of Red list classes above
and NatureServe status below
Examples of species and subspecies that are extinct in the wild include:
- Alagoas curassow (last unconfirmed sighting reported in the late 1980s, listed extinct in the wild since 1994)
- Black soft-shell turtle (listed extinct in the wild since 2002)
- Cachorrito de charco palmal (last seen in 1994, listed extinct in the wild since 1996)
- Escarpment cycad (listed extinct in the wild since 2006)
- Fernandina Island tortoise 
- Franklinia (last seen in 1803, listed extinct in the wild since 1998)
- Golden skiffia (listed extinct in the wild since 1996)
- Guam kingfisher (listed extinct in the wild since 1986)
- Hawaiian crow or ʻalalā (last seen in 2002, listed as extinct in the wild since 2004) Small groups have since been released in 2017 and 2018.
- Kihansi spray toad (listed extinct in the wild since 2009)
- Northern white rhinoceros (possibly extinct in the wild)
- Oahu deceptor bush cricket (listed extinct in the wild since 1996)
- Panamanian golden frog (possibly extinct in the wild)
- Père David's deer (listed extinct in the wild since 2008. However, reintroduction from captive populations began in 1985, with 53 wild herds of varying sizes being recorded in 2003)
- Scimitar oryx (listed extinct in the wild since 2000. A herd of 21 was successfully released into the wild in Chad in 2016, producing the first offspring born in the wild in over 20 years in 2017)
- Socorro dove (listed extinct in the wild since 1994)
- Socorro isopod (last seen in 1988, listed as extinct in the wild since August 1996)
- South China tiger (since 2008 IUCN Red List lists as critically endangered; possibly extinct in the wild)
- Spix's macaw (listed extinct in the wild since June 2019)
- Wyoming toad (listed extinct in the wild since 1991, although 853 have been released into the wild since 1995, leading to a population of around 1,500 in 2017)
The Pinta Island tortoise (Geochelone nigra abingdoni) had only one living individual, named Lonesome George, until his death in June 2012. The tortoise was believed to be extinct in the mid-20th century, until Hungarian malacologist József Vágvölgyi spotted Lonesome George on the Galapagos island of Pinta on 1 December 1971. Since then, Lonesome George has been a powerful symbol for conservation efforts in general and for the Galapagos Islands in particular. With his death on 24 June 2012, the subspecies is again believed to be extinct. With the discovery of 17 hybrid Pinta tortoises located at nearby Wolf Volcano a plan has been made to attempt to breed the subspecies back into a pure state.
Not all EW species are rare. An example is the Brugmansia family, where all seven species are widely cultivated but none are found in the wild. Ultimately, the purpose of preserving biodiversity is to maintain ecological function, so when a species exists only in captivity, it is ecologically extinct.
Reintroduction is the deliberate release of individuals into the wild, from captivity or from other areas where the species survives. However, it may be difficult to reintroduce EW species into the wild, even if their natural habitats were restored, because survival techniques, which are often passed from parents to offspring during parenting, may have been lost.
An example of a successful reintroduction of a formerly EW species is Przewalski's horse, which as of 2018 is considered to be an endangered species, following reintroduction started in the 1990s.
- IUCN Red List extinct in the wild species for a list by taxonomy
- Category:IUCN Red List extinct in the wild species for an alphabetical list
- "2001 IUCN Red List Categories and Criteria: Version 3.1" (PDF). IUCN. p. 14. Archived from the original (PDF) on 21 June 2010. Retrieved 30 May 2010.
- "Alagoas Curassow (Mitu mitu)". IUCN Red List.
- Freyhof, J.; Kottelat, M. (2008). "Stenodus leucichthys". IUCN Red List of Threatened Species. 2008: e.T20745A9229071. doi:10.2305/IUCN.UK.2008.RLTS.T20745A9229071.en.
- "Black Softshell Turtle (Nilssonia nigricans)". IUCN Red List.
- "La Palma Pupfish (Cyprinodon longidorsalis)". IUCN Red List.
- Donaldson, J.S. (2010). "Encephalartos brevifoliolatus". IUCN Red List of Threatened Species. 2010: e.T41882A10566751. doi:10.2305/IUCN.UK.2010-3.RLTS.T41882A10566751.en.[permanent dead link]
- Rhodin, A.G.J.; Gibbs, J.P.; Cayot, L.J.; Kiester, A.R.; Tapia, W. (2017). "Chelonoidis phantasticus (errata version published in 2018)". IUCN Red List of Threatened Species. 2017. Retrieved 22 February 2019.
- "Franklin Tree (Franklinia alatamaha)". IUCN Red List.
- "Golden Skiffia (Skiffia francesae)". IUCN Red List.
- "Guam Kingfisher (Todiramphus cinnamominus)". IUCN Red List.
- "Hawaiian Crow (Corvus hawaiiensis)". IUCN Red List.
- "'ALALĀ RELEASED INTO NATURAL AREA RESERVE". Aliso Laguna News.
- "Rare Hawaiian crows released into native forests of Hawai'i Island". KITV4.
- "Five more alala released into Puu Makaala Forest Reserve". West Hawaii Today.
- "Nectophrynoides asperginis". IUCN Red List.
- Emslie, R. (2020). "Northern White Rhino". IUCN Red List of Threatened Species. 2020. Retrieved 8 May 2020.old-form url
- "Leptogryllus deceptor". IUCN Red List.
- "'Last wave' for wild golden frog". BBC. 2 February 2008. Retrieved 22 February 2015.
- "Père David's Deer (Elaphurus davidianus)". IUCN Red List.
- Yang, R., Zhang, L., Tan, B. and Zhong, Z. 2003. Investigation on the status of Père David’s deer in China. Chinese Journal of Zoology 38: 76~81.
- "Scimitar-horned Oryx (Oryx dammah)". IUCN Red List.
- "Scimitar-horned oryx returns to Sahara". Zoological Society of London.
- "Zenaida graysoni (Socorro Dove)". IUCN Red List.
- "Thermosphaeroma thermophilum". IUCN Red List.
- "South China Tiger". World Wide Fund for Nature.
- "Panthera tigris amoyensis". IUCN Red List.
- "Spix's Macaw". IUCN Red List.
- "Wyoming Toads Begin To Recover As States Seek Endangered Species Act Overhaul". NPR.
- Gardner, Simon (6 February 2001). "Lonesome George faces own Galapagos tortoise curse". Archived from the original on 4 June 2011.
- Nicholls, H. (2006). Lonesome George: The Life and Loves of a Conservation Icon. London, England: Macmillan Science. ISBN 1-4039-4576-4. Archived from the original on 14 September 2011. Retrieved 28 April 2011.
- "Last Pinta giant tortoise Lonesome George dies". BBC News. 24 June 2012. Retrieved 25 June 2012.
- "Scientists: Extinct Galapagos tortoise species could be resurrected". CTV News. 22 November 2012. Retrieved 25 November 2012.
- Petruzzello, Melissa. "Extinct in the Wild but Still Around: 5 Plants and Animals Kept Alive by Humans". ENCYCLOPÆDIA BRITANNICA. ENCYCLOPÆDIA BRITANNICA. Retrieved 16 November 2019.
- "An extraordinary return from the brink of extinction for worlds last wild horse". 19 December 2005. Archived from the original on 12 February 2012. Retrieved 5 March 2018.