extinct in the wild

File:Corvus hawaiiensis FWS.jpg has been listed as extinct in the wild since 2004.]]

File: Guam Micronesian Kingfisher at Bronx Zoo-8-4c.jpg has been extinct in the wild since 1986.]]

A species that is extinct in the wild (EW) is one that has been categorized by the International Union for Conservation of Nature as only consisting of living members kept in captivity or as a naturalized population outside its historic range.{{cite web |title=2001 IUCN Red List Categories and Criteria: Version 3.1 |url=https://www.iucnredlist.org/documents/redlist_cats_crit_en.pdf |url-status=dead |archive-url=https://web.archive.org/web/20100621095221/https://www.iucnredlist.org/documents/redlist_cats_crit_en.pdf |archive-date=21 June 2010 |access-date=30 May 2010 |publisher=IUCN |page=14 }}{{Cite web |title=The IUCN Red List Categories and Criteria |url=https://www.iucnredlist.org/ |website=IUCN Red List }} Classification requires exhaustive surveys conducted within the species' known habitat with consideration given to seasonality, time of day, and life cycle.IUCN. (2003). [https://portals.iucn.org/library/sites/library/files/documents/RL-2003-001-EN.pdf Guidelines for Application of IUCN Red List Criteria at Regional Levels: Version 3.0]. IUCN Species Survival Commission. IUCN, Gland, Switzerland and Cambridge, UK. ii + 26 pp. Once a species is classified as EW, the only way for it to be downgraded is through reintroduction.{{Cite web |title=Reasons for Changing Category |url=https://www.iucnredlist.org/assessment/reasons-changing-category |website=IUCN Red List }}

Not all EW species are rare. An example is the Brugmansia genus, where all seven species are widely cultivated, but none are found in the wild.{{cite web |last1=Petruzzello |first1=Melissa |title=Extinct in the Wild but Still Around: 5 Plants and Animals Kept Alive by Humans |url=https://www.britannica.com/list/extinct-in-the-wild-but-still-around-5-plants-and-animals-kept-alive-by-humans |access-date=16 November 2019 |website=Encyclopædia Britannica }} Ultimately, the purpose of preserving biodiversity is to maintain ecological function to prevent ecological extinction.

Examples

Examples of species and subspecies that are extinct in the wild include (in alphabetical order):

Abutilon pitcairnense (last surviving plant destroyed in 2005){{cite iucn |author=Bárrios, S. |author2=Smyth, N. |date=2018 |title=Abutilon pitcairnense |volume=2018 |page=e.T122926206A122926208 |access-date=16 December 2023 }}
Alagoas curassow (last unconfirmed sighting reported in the late 1980s, listed extinct in the wild since 1994){{cite iucn |url=https://www.iucnredlist.org/species/22678486/132315266#assessment-information |title=Alagoas Curassow (Mitu mitu) |date=7 August 2018 |url-status=live |archive-url=https://web.archive.org/web/20231215043257/https://www.iucnredlist.org/species/22678486/132315266 |archive-date=15 December 2023 }}
Beloribitsa{{Cite iucn |author1=Freyhof, J. |author2=Kottelat, M. |title=Stenodus leucichthys (Caspian Inconnu) |volume=2008 |page=e.T20745A9229071 |date=2008 |doi=10.2305/IUCN.UK.2008.RLTS.T20745A9229071.en |url-status=live |archive-url=https://web.archive.org/web/20231215042501/https://www.iucnredlist.org/species/20745/9229071 |archive-date=15 December 2023 }}
Corypha taliera (last tree cut down in 1979){{cite iucn |author=Johnson, D. |date=1998 |title=Corypha taliera |volume=1998 |page=e.T38493A10118302 |access-date=16 December 2023 }}
Christmas Island blue-tailed skink (listed extinct in the wild since 2014){{cite iucn |title=Christmas Island Blue-tailed Shinning-skink (Cryptoblepharus egeriae) |date=20 February 2017 |url=https://www.iucnredlist.org/species/102327291/102327566 |url-status=live |archive-url=https://web.archive.org/web/20231215035856/https://www.iucnredlist.org/species/102327291/102327566 |archive-date=15 December 2023 }}
Dabry's sturgeon (listed extinct in the wild since 2022){{cite iucn |author=Qiwei, W. |date=2022 |title=Acipenser dabryanus (Yangtze Sturgeon) |page=e.T231A61462199 |access-date=3 September 2022 |url-status=live |archive-url=https://web.archive.org/web/20231215035428/https://www.iucnredlist.org/species/231/61462199 |archive-date=15 December 2023 }}
Escarpment cycad (listed extinct in the wild since 2006){{Cite iucn |last=Donaldson |first=J.S. |title=Encephalartos brevifoliolatus (Escarpment Cycad) |date=2010 |page=e.T41882A10566751 |doi=10.2305/IUCN.UK.2010-3.RLTS.T41882A10566751.en }}
Franklinia alatamaha (last seen in 1803, listed extinct in the wild since 1998){{cite iucn |url=https://www.iucnredlist.org/species/30408/62077322#assessment-information |title=Franklin Tree (Franklinia alatamaha) |date=3 February 2015 |url-status=live |archive-url=https://web.archive.org/web/20231215033516/https://www.iucnredlist.org/species/30408/62077322 |archive-date=15 December 2023 }}
Golden skiffia (listed extinct in the wild since 1996){{cite iucn |url=https://www.iucnredlist.org/species/20285/2757376#assessment-information |title=Golden Skiffia (Skiffia francesae) |date=18 April 2018 |url-status=live |archive-url=https://web.archive.org/web/20231215031928/https://www.iucnredlist.org/species/20285/2757376 |archive-date=15 December 2023 }}
Guam kingfisher (listed extinct in the wild since 1986){{cite iucn |url=https://www.iucnredlist.org/species/22725862/117372355#assessment-information |title=Guam Kingfisher (Todiramphus cinnamominus) |date=October 2016 |url-status=live |archive-url=https://archive.today/20231215030917/https://www.iucnredlist.org/species/22725862/117372355%23assessment-information |archive-date=15 December 2023 }}
Hawaiian crow or ʻalalā (last seen in 2002, listed as extinct in the wild since 2004){{cite iucn |url=https://www.iucnredlist.org/species/22706052/94048187#assessment-information |title=Hawaiian Crow (Corvus hawaiiensis) |date=October 2016 |url-status=live |archive-url=https://web.archive.org/web/20230612175608/https://www.iucnredlist.org/species/22706052/94048187#assessment-information |archive-date=12 June 2023 }} Small groups have since been released in 2017{{cite web |url=http://www.alisolagunanews.com/alala-released-into-natural-area-reserve/ |title='Alalā released into natural area reserve |publisher=Aliso Laguna News |date=27 September 2017 |first1=Susan |last1=Keysor Espenschied |url-status=live |archive-url=https://web.archive.org/web/20230427090101/https://www.alisolagunanews.com/alala-released-into-natural-area-reserve/ |archive-date=27 April 2023 }}{{cite web |url=https://www.kitv.com/story/36609266/rare-hawaiian-crows-released-into-native-forests-of-hawaii-island |title=Rare Hawaiian crows released into native forests of Hawai'i Island |publisher=KITV4 |date=16 October 2017 |first1=Diane |last1=Ako |access-date=10 February 2020 |archive-date=24 October 2021 |archive-url=https://web.archive.org/web/20211024121436/https://www.kitv.com/story/36609266/rare-hawaiian-crows-released-into-native-forests-of-hawaii-island |url-status=dead }} and 2018.{{cite web |url=https://www.westhawaiitoday.com/2018/10/01/hawaii-news/go-for-crow/ |title=Five more alala released into Puu Makaala Forest Reserve |date=1 October 2018 |first1=Michael |last1=Brestovansky |publisher=West Hawaii Today |url-status=live |archive-url=https://web.archive.org/web/20230510141532/https://www.westhawaiitoday.com/2018/10/01/hawaii-news/go-for-crow/ |archive-date=10 May 2023 }}
Kihansi spray toad (listed extinct in the wild since 2009){{cite iucn |url=https://www.iucnredlist.org/species/54837/16935685#assessment-information |title=Nectophrynoides asperginis |date=25 July 2014 }}
La Palma pupfish (last seen in 1994, listed extinct in the wild since 1996){{cite iucn |url=https://www.iucnredlist.org/species/6174/3107266#assessment-information |title=La Palma Pupfish (Cyprinodon longidorsalis) |date=27 September 2018 |url-status=live |archive-url=https://web.archive.org/web/20231215041417/https://www.iucnredlist.org/species/6174/3107266 |archive-date=15 December 2023 }}
Lister's gecko (listed extinct in the wild since 2014){{cite iucn |title=Christmas Island Chained Gecko (Lepidodactylus listeri) |date=20 February 2017 |url=https://www.iucnredlist.org/species/11559/83321765 }}
Oahu deceptor bush cricket (listed extinct in the wild since 1996){{cite iucn |url=https://www.iucnredlist.org/species/11690/3301867#assessment-information |title=Leptogryllus deceptor |date=August 1996 }}
Panamanian golden frog (possibly extinct in the wild){{Cite web |url=http://news.bbc.co.uk/2/hi/science/nature/7219803.stm |access-date=22 February 2015 |date=2 February 2008 |title='Last wave' for wild golden frog |publisher=BBC }}
Père David's deer (listed extinct in the wild since 2008.{{cite iucn |url=https://www.iucnredlist.org/species/7121/22159785#assessment-information |title=Père David's Deer (Elaphurus davidianus) |date=31 March 2016 }} However, reintroduction from captive populations began in 1985, with 53 wild herds of varying sizes being recorded in 2003){{cite journal|author=Yang, R.|author2= Zhang, L.|author3= Tan, B. |author4= Zhong, Z. |year=2003|title= Investigation on the status of Père David's deer in China|journal= Chinese Journal of Zoology |volume=38|pages= 76–81}}
Partula species (listed extinct in the wild in the 1990s):
Niho tree snail
Miracle Partula
Moorean Smooth Partula
Sutural Partula
Rose-tipped Partula
Garrett's Partula
Raiatea ground Partula
Pink Partula
Variable Partula
Simandoa conserfariam {{cite web|url=https://arthroverts.org/conserfariam-roach/ |title=Simandoa conserfarium (Simandoa Cave Roach) |website=arthroverts.org }}
Socorro dove (listed extinct in the wild since 1994){{cite iucn |url=https://www.iucnredlist.org/species/22690740/93286172 |title=Zenaida graysoni (Socorro Dove) |date=1990s }}
Socorro isopod (last seen in 1988, listed as extinct in the wild since August 1996){{cite iucn |url=https://www.iucnredlist.org/species/21741/9315891 |title=Thermosphaeroma thermophilum |date=August 1996 }}
South China tiger (since 2008 IUCN Red List lists as critically endangered; possibly extinct in the wild){{cite web |url=https://www.worldwildlife.org/species/south-china-tiger |title=South China Tiger |publisher=World Wide Fund for Nature }}{{cite iucn |url=https://www.iucnredlist.org/species/15965/5334628 |title=Panthera tigris amoyensis |date=30 June 2008 }}
Spix's macaw (listed extinct in the wild since June 2019){{cite iucn |url=https://www.iucnredlist.org/species/22685533/153022606 |title=Spix's Macaw |date=20 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){{cite web |url=https://www.npr.org/2017/06/19/533203933/wyoming-toads-rebound-as-states-seek-endangered-species-act-reforms?t=1581297210546www.iucnredlist.org/species/22690740/93286172 |title=Wyoming Toads Begin To Recover As States Seek Endangered Species Act Overhaul |publisher=NPR }}

Conservation

=Reintroduction=

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. Reintroduction efforts, also referred to as translocation, are complex and a common source of complication is how animals behave upon release.{{Cite journal |last1=Berger-Tal |first1=O. |last2=Blumstein |first2=D. T. |last3=Swaisgood |first3=R. R. |date=April 2020 |title=Conservation translocations: a review of common difficulties and promising directions |url=https://zslpublications.onlinelibrary.wiley.com/doi/10.1111/acv.12534 |journal=Animal Conservation |language=en |volume=23 |issue=2 |pages=121–131 |doi=10.1111/acv.12534 |bibcode=2020AnCon..23..121B |issn=1367-9430 }} Climate suitability has been shown to influence reintroduction outcomes as well.{{Cite journal |last1=Bellis |first1=Joe |last2=Bourke |first2=David |last3=Maschinski |first3=Joyce |last4=Heineman |first4=Katie |last5=Dalrymple |first5=Sarah |date=December 2020 |title=Climate suitability as a predictor of conservation translocation failure |journal=Conservation Biology |language=en |volume=34 |issue=6 |pages=1473–1481 |doi=10.1111/cobi.13518 |issn=0888-8892 |doi-access=free |pmid=32304113 |bibcode=2020ConBi..34.1473B }} Though many efforts translocate populations to historic ranges, climate change may be causing those previously inhabited areas to no longer be suitable for the species.

File:Observation_des_chevaux_de_Przewalski_(Equus_ferus_przewalskii).jpg has been reintroduced, its status going from extinct in the wild to endangered.]]

The Przewalski's horse was downgraded from EW to Endangered in 2011 after decades of reintroduction efforts.{{Cite journal |last1=Turghan |first1=Mardan Aghabey |last2=Jiang |first2=Zhigang |last3=Niu |first3=Zhongze |date=15 November 2022 |title=An Update on Status and Conservation of the Przewalski's Horse (Equus ferus przewalskii): Captive Breeding and Reintroduction Projects |journal=Animals |volume=12 |issue=22 |pages=3158 |doi=10.3390/ani12223158 |issn=2076-2615 |doi-access=free |pmid=36428386 |pmc=9686875 }} In China, they are still classified as EW since they are given supplemental feed over the winter to aid survival. Of the 2500 living, about 1360 are in the wild, and all 2500 are descended from 12 wild-caught ancestors, causing an inbreeding depression that contributes to factors, such as shorter lifespans and high mortality, that impede conservation.

File:Northern_White_Rhinoceros_Angalifu.jpg, an EW species, at the San Diego Zoo Safari Park]]

Northern white rhinos have been extinct in the wild since 2007, and only two females remain in captivity.{{Cite journal |last1=Ryder |first1=Oliver A. |last2=Friese |first2=Carrie |last3=Greely |first3=Henry T. |last4=Sandler |first4=Ronald |last5=Saragusty |first5=Joseph |last6=Durrant |first6=Barbara S. |last7=Redford |first7=Kent H. |date=August 2020 |title=Exploring the limits of saving a subspecies: The ethics and social dynamics of restoring northern white rhinos (Ceratotherium simum cottoni) |journal=Conservation Science and Practice |language=en |volume=2 |issue=8 |doi=10.1111/csp2.241 |issn=2578-4854 |doi-access=free |bibcode=2020ConSP...2E.241R }} The San Diego Zoo Global is planning to save the species by using living cells from 12 rhinos that have been cryopreserved, turning them into stem cell lines, using in vitro fertilization to create embryos, and then having Southern white rhinos serve as surrogates. Currently, there have been no successful embryo transfers in rhinos. It is estimated to take at least 40 years for the target of 25–40 northern white rhinos to be reached.

Some people critique efforts to save species with such small populations due to the possibility of inbreeding as it can reduce the population growth rate.{{Cite journal |last1=Bozzuto |first1=Claudio |last2=Biebach |first2=Iris |last3=Muff |first3=Stefanie |last4=Ives |first4=Anthony R. |last5=Keller |first5=Lukas F. |date=2 September 2019 |title=Inbreeding reduces long-term growth of Alpine ibex populations |url=https://www.nature.com/articles/s41559-019-0968-1 |journal=Nature Ecology & Evolution |language=en |volume=3 |issue=9 |pages=1359–1364 |doi=10.1038/s41559-019-0968-1 |pmid=31477848 |bibcode=2019NatEE...3.1359B |issn=2397-334X |hdl=11250/2637691 |hdl-access=free }} Small effective population sizes are another critique. Effective population size is a measurement of the loss of genetic diversity.{{Cite journal |last1=Husemann |first1=M |last2=Zachos |first2=F E |last3=Paxton |first3=R J |last4=Habel |first4=J C |date=October 2016 |title=Effective population size in ecology and evolution |journal=Heredity |language=en |volume=117 |issue=4 |pages=191–192 |doi=10.1038/hdy.2016.75 |issn=0018-067X |pmc=5026761 |pmid=27553454 |bibcode=2016Hered.117..191H }} Multiple populations have been found to have an effective population size below conservation goals. Additionally, monitoring effective population size and using it to aid estimations of the success of conservation efforts has been shown to provide a better overview of determining population trends when compared to population size.{{Cite journal |last1=Wang |first1=J |last2=Santiago |first2=E |last3=Caballero |first3=A |date=October 2016 |title=Prediction and estimation of effective population size |journal=Heredity |language=en |volume=117 |issue=4 |pages=193–206 |doi=10.1038/hdy.2016.43 |issn=0018-067X |pmc=5026755 |pmid=27353047 |bibcode=2016Hered.117..193W }}

= IUCN Green Status of Species =

File:Brugmansia A.jpg, Since March 2014, they have been listed as Extinct in the Wild by the IUCN. ]]

The IUCN developed a system of classifying species recovery efforts in 2012 entitled the Green Status.{{Cite journal |last1=Grace |first1=Molly K. |last2=Akçakaya |first2=H. Resit |last3=Bennett |first3=Elizabeth L. |last4=Brooks |first4=Thomas M. |last5=Heath |first5=Anna |last6=Hedges |first6=Simon |last7=Hilton-Taylor |first7=Craig |last8=Hoffmann |first8=Michael |last9=Hochkirch |first9=Axel |last10=Jenkins |first10=Richard |last11=Keith |first11=David A. |last12=Long |first12=Barney |last13=Mallon |first13=David P. |last14=Meijaard |first14=Erik |last15=Milner-Gulland |first15=E.J. |date=December 2021 |title=Testing a global standard for quantifying species recovery and assessing conservation impact |url=https://conbio.onlinelibrary.wiley.com/doi/10.1111/cobi.13756 |journal=Conservation Biology |language=en |volume=35 |issue=6 |pages=1833–1849 |doi=10.1111/cobi.13756 |pmid=34289517 |bibcode=2021ConBi..35.1833G |issn=0888-8892 |hdl=10919/108163 |hdl-access=free }} The species recovery score is a 0%–100% scale, with 0% being the species is extinct or extinct in the wild and 100% being fully recovered. In addition, the Green Status also classifies previous and future conservation impacts with the Green Scores of Conservation Dependency, Conservation Gain, Conservation Legacy, and Recovery Potential.{{Cite web |title=The IUCN Green Status of Species |url=https://www.iucnredlist.org/about/green-status-species |website=IUCN Red List }}

For a species to receive a score of 100% and be considered fully recovered, three requirements must be met: the species must be present in all areas of both its current and historical range, it is viable in all areas of the range, and performs its ecological niche across the full range. Given the lofty standards, many species are not expected to meet the criteria and it is not a goal of this system. Land use changes have cumulated in many species losing habitat.

Green Scores are snapshots in time to assess a species' current status and how conservation efforts have influenced their status. It is also predictive as it can project how the status would change if conservation efforts ceased or continued. Conservation Legacy assess how previous conservation work has changed or maintained a species' status. The score ranges from high to low with low meaning conservation efforts were ineffective or did not occur. Conservation Dependency is the estimate of a species' status in 10 years if conservation efforts halted. High dependency means the species would have a lower status and low dependency equates to the status not changing. Conservation Gain is the flip side. It projects a species' status in 10 years if conservation efforts continue. Both dependence and gain are considered short-term measures. The long-term measure is Recovery Potential, which is how much of the range is estimated to be able to house ecologically functional populations.

= Flagship species =

File:Pinta_Island_Tortoise_Lonesome_George_2008.jpg]]

The Pinta Island tortoise (Geochelone nigra abingdoni) had only one living individual, named Lonesome George, until his death in June 2012.{{cite web |last=Gardner |first=Simon |date=6 February 2001 |title=Lonesome George faces own Galapagos tortoise curse |url=http://www.planetark.com/dailynewsstory.cfm/newsid/9708/newsDate/06-Feb-2001/story.htm |url-status=usurped |archive-url=https://web.archive.org/web/20110604055952/http://www.planetark.com/dailynewsstory.cfm/newsid/9708/newsDate/06-Feb-2001/story.htm |archive-date=4 June 2011 }} 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.{{cite book |last=Nicholls |first=H. |url=http://myweb.tiscali.co.uk/henry |title=Lonesome George: The Life and Loves of a Conservation Icon |publisher=Macmillan Science |year=2006 |isbn=1-4039-4576-4 |location=London, England |access-date=28 April 2011 |archive-url=https://web.archive.org/web/20110914155707/http://myweb.tiscali.co.uk/henry/ |archive-date=14 September 2011 |url-status=dead }} With his death on 24 June 2012, the subspecies is again believed to be extinct.{{cite web |date=24 June 2012 |title=Last Pinta giant tortoise Lonesome George dies |url=https://www.bbc.co.uk/news/world-18574279 |access-date=25 June 2012 |work=BBC News }} 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.{{cite web |date=22 November 2012 |title=Scientists: Extinct Galapagos tortoise species could be resurrected |url=https://www.ctvnews.ca/mobile/sci-tech/scientists-extinct-galapagos-tortoise-species-could-be-resurrected-1.1049936 |access-date=25 November 2012 |work=CTV News }}