Yangtze giant softshell turtle
Yangtze giant softshell turtle | |
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One of the two R. swinhoei of Dong Mo, Son Tay , Vietnam
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Reptilia |
Order: | Testudines |
Suborder: | Cryptodira |
Family: | Trionychidae |
Genus: | Rafetus |
Species: | R. swinhoei
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Binomial name | |
Rafetus swinhoei (Gray, 1873)
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Yangtze giant softshell turtle range | |
Synonyms[3] | |
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The Yangtze giant softshell turtle (Rafetus swinhoei), also known
Description
The Yangtze giant softshell turtle is noted for its deep head with a pig-like snout and
Known individuals
Only two or three living individuals are known: one in China (captive) and one or two in Vietnam (wild).[12] Following the deaths of a wild individual in Vietnam in January 2016 and a captive individual in China in 2019, the species is listed as Critically Endangered in the IUCN Red List. The female of the last breeding pair died at Suzhou Zoo in China in April 2019.[13][14][15] A wild female was discovered in Vietnam on October 22, 2020; however, this last wild female was found dead in early 2023.[16][17][12][18] Another individual is believed to have been sighted in the same area.
Geographic range
The Yangtze giant softshell turtle has been known to inhabit the
A specimen at the Beijing Zoo died in 2005, and another one at the Shanghai Zoo died in 2006; both of them were caught at Gejiu in the 1970s.[19] In 1999, 2000, and 2005, turtles re-emerged from Hoan Kiem Lake in Hanoi and were seen by a large audience and caught on film. Only a single turtle was believed to be left in the lake.[20] In April 2011, it was captured because it had open sores (possibly due to refuse and pollution in the lake, injuries from fishing hooks or other turtles) that needed to be treated.[21] It was reported dead in January 2016.[22] On April 13, 2019, the only female turtle in Suzhou Zoo was reported dead shortly after the latest fertilization process.[13][14] In 2020, a new female was found in Vietnam's Dong Mo Lake, and it is believed that another individual (of unspecified gender) is also living in the lake. It is also discovered that there is also another individual living in the nearby Xuan Khanh Lake.[12] The Dong Mo specimen died in April 2023, leaving the turtles at Suzhou Zoo (possibly Dong Mo Lake) as well as Xuan Khanh Lake as the last two or three recognized surviving members of this species.[18][23]
Ecology and behaviour
Diet
R. swinhoei eats
]Reproduction
The Yangtze giant softshell turtle may lay from 20 to more than 80 eggs. It nests at night and during the morning.[11]
A fertile female from the
Behavior
Despite its massive size and distinctive appearance, this species is extremely secretive and only rarely comes up to breathe, largely preferring to stay submerged deep underwater. This may be part of the reason why it is so difficult to positively identify and confirm wild sightings of this species.[26]
Relationship with humans
Scientific description and systematics
The species became known to Western science in 1873, when John Edward Gray, the turtle expert at the British Museum, described the specimen sent to him from Shanghai by English biologist Robert Swinhoe.[27] He named the species Oscaria swinhoei, and described it as "the most beautiful species of Trionychidae that has yet occurred."[28]
In 1880, the Shanghai-based French
Later zoologists classified these turtles as belonging to the genera Trionyx, Pelodiscus, and Pelochelys; in 1987, Meylan categorized this species under the genus Rafetus.[29]
The placement of the related or conspecific
Key threats
The Yangtze giant softshell turtle is on the brink of extinction due to
Conservation efforts
External image | |
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One individual in Suzhou Zoo, 2008.[33] |
Captive breeding
Conservation efforts are concentrated on breeding captive turtles in China and searching for live specimens in the wild. An agreement was made to transfer the only known remaining female specimen located at the Changsha Zoo to the Suzhou Zoo to breed with the male specimen there. Also, efforts are being made to improve conditions for breeding at both the Suzhou Zoo and Western Temple in Suzhou. A workshop on the Rafetus Conservation at Yunnan was held by CI-Shanshui. Local Chinese scientists are searching for the last existent individuals.[34] The two specimens were able to produce two clutches of eggs, with over half of them being fertile, though all of them perished before hatching.[35] The Turtle Survival Alliance released a statement saying, "A number of the eggs had very thin shells, suggesting that the diet of the animals prior to breeding was not optimal."[36] The two turtles were prepared for another round of mating, while being fed a high-calcium diet in an effort to strengthen the eggs. Liu Jinde, the director of the zoo said, "We've worked very hard on this, We ought to succeed. The turtles are very healthy."
The scientists began preparing to mate the two once again in May 2009, which fell within this species' breeding season,
In 2015 artificial insemination was attempted, a first for this species.[39] In May 2015, the female was successfully inseminated. Semen was extracted from the sedated male using electro-ejaculation. By late July, the female had laid 2 clutches of eggs, totaling 89 eggs, but none were viable.[40] The female later died in April 2019 following another artificial insemination attempt.[13][14][15]
Surveys for surviving specimens
As of mid-2017, conservationists are searching for any possible wild individuals in the remote parts of China. A major target of the survey are parts of the Red River in Yunnan Province. Locals in the area have reported seeing 1-2 turtles that have a similar description to that of this species, meaning that there is a small possibility the species may still survive in the wild.[41] In Oct. 2018, the Asian Turtle Program announced that it was interviewing local people to collect data to guideline searches for R. swinhoei in the very large area of flooded valleys formed by damming the Da River.[42]
Rediscovered individuals
In April 2018, conservationists confirmed the existence of a second wild individual in Xuan Khanh Lake, Vietnam. The individual was photographed two times in 2012 and 2017, but both times the photograph was blurry and provided little confirmation of its identity. Using traces of the turtle's DNA in the lake's water, the specimen's identity was confirmed as R. swinhoei.[43] In Nov. 2018, it was announced that a second, smaller individual of R. swinhoei also lives in Dong Mo Lake; this individual had long been confused with the larger turtle until the summer of 2018, when both turtles were seen raising their heads out of the water at the same time.[44] In 2020, a survey at Dong Mo managed to capture one of the turtles and obtain genetic samples, and found that it was a female, representing the first known female R. swinhoei since the death of the captive female in 2019.[16] This female died from unknown causes in early 2023.[18]
There are also several other modern accounts of surviving individuals of R. swinhoei, although most of these are unverified or have not been followed up on. Following the creation of the Madushan Dam in China's Yunnan Province, local fishermen regularly reported sightings of one to two very large softshell turtles in the reservoir. However, extensive surveys in 2016 and 2017 were unsuccessful in finding any such turtles.[45] At some point prior to 2015, a survey team from the conservation group Turtle Island apparently managed to locate an individual of R. swinhoei in a section of the Red River between two reservoirs. However, the individual was never trapped and was at high risk of being caught by fishermen.[46] Another search by the same group found a pond in Laos where a R. swinhoei had apparently lived for over 45 years before a monsoon in 2013, during which the individual moved to a nearby river and was never seen again.[46]
The legend of Kim Qui
The specimen (which may be a distinct species R. leloii) located in Hoan Kiem Lake, in Hanoi is thought to be the legendary
In the 15th century, a gentry named
References
- ^ a b Fong, J.; Hoang, H.; Kuchling, G.; Li, P.; McCormack, T.; Rao, D.-Q.; Timmins, R.J.; Wang, L. (2022). "Yangtze Giant Softshell Turtle". IUCN Red List of Threatened Species. 2022. Retrieved 22 October 2022.
- ^ "Appendices | CITES". cites.org. Retrieved 2022-01-14.
- ISSN 1864-5755.
- ^ "Almost Extinct Turtle Discovered Living In Wild In Northern Vietnam". ScienceDaily. Retrieved 2014-06-16.
- ^ Dudgeon D (2010). "Requiem for a river: extinctions, climate change and the last of the Yangtze". Aquatic Conservation: Marine and Freshwater Ecosystems 20 (2): 127-131.
- ^ "World's Largest Freshwater Turtle Nearly Extinct". National Geographic. 2013-07-01. Archived from the original on July 7, 2013. Retrieved 2014-07-22.
- ^ Jian W, Hai-Tao S, Cheng W, Lian-Xian H (2013). "Habitat Selection and Conservation Suggestions for the Yangtze Giant Softshell Turtle (Rafetus swinhoei ) in the Upper Red River, China". Chelonian Conservation and Biology 12 (1): 177-184.
- ^ Le DM, Pritchard P (2009). "Genetic variability of the critically endangered softshell turtle, Rafetus swinhoei: a preliminary report". pp. 84-92. In: Ngo DC, Ta HT, Le NN, Hoang XQ, Vo VP, Nguyen VS, Nguyen VT, Le TT, Tran QD (eds.) (2009). Proceedings of the First National Science Workshop on Amphibians and Reptiles in Vietnam. Hue: Hue University Press.
- ^ a b Farkas, Balázs; Minh Duc Le; Truong Quang Nguyen (2011). "Rafetus vietnamensis Le, Le, Tran, Phan, Phan, Tran, Pham, Nguyen, Nong, Phan, Dinh, Truong and Ha, 2010 – another invalid name for an invalid species of softshell turtle (Reptilia: Testudines: Trionychidae)". Russian Journal of Herpetology. 18 (1): 65–72. Retrieved 17 February 2012.
- ^ a b Farkas B, Webb RG (2003). "Rafetus leloii Hà Dinh Dúc, 2000—an invalid species of softshell turtle from Hoan Kiem Lake, Hanoi, Vietnam (Reptilia, Testudines, Trionychidae)". Zoologische Abhandlungen. 53: 107–112.
- ^ a b c "Species: Rafetus swinhoei ". Asian Turtle Conservation Network. Archived from the original on 2006-12-14. Retrieved 2006-12-09.
- ^ a b c Carrington, Damian (January 2021). "Hopes for most endangered turtle after discovery of female in Vietnam lake". The Guardian. Retrieved 7 May 2022.
- ^ a b c "苏州动物园一只斑鳖人工受精后死亡,世界目前已知的仅剩三只" (in Chinese). Sohu.com. 2019-04-13. Retrieved 2019-04-14.
- ^ a b c "'Last female' of rare turtle species dies in China zoo". Al Jazeera English. 2019-04-14. Retrieved 2019-04-14.
- ^ a b Shams, Shamil. "Death of rare Yangtze giant softshell turtle leaves 3 remaining in the world". DW.COM. Retrieved 2019-04-16.
- ^ a b "World's Most Endangered Turtle Gets Some Good News In 2020". newsroom.wcs.org. Retrieved 2020-12-19.
- ^ "New discovery gives world's most endangered turtle a fighting chance". www.downtoearth.org.in. Retrieved 2021-08-09.
- ^ a b c "Rare, Revered Reptile on Brink of Extinction After Last Female Dies". Time. 2023-04-28. Retrieved 2023-05-06.
- ^ "Draft Action Plan – Rafetus swinhoei " (PDF). Turtle Survival Alliance. Archived from the original (PDF) on June 21, 2007. Retrieved 2006-12-09.
- ^ a b c "Hoan Kiem Lake Turtle: from myth to reality". VietNamNet Bridge. 2005. Archived from the original on 2006-12-07. Retrieved 2006-12-09.
- ^ "Vietnam hauls in beloved turtle for medical treatment". BBC. 2011-04-03. Retrieved 2011-04-03.
- ^ Cu Rua: Vietnam mourns revered Hanoi turtle, BBC News, 20 January 2016
- ^ "Thế giới còn bao nhiêu cá thể rùa Hoàn Kiếm?". Báo điện tử Tiền Phong (in Vietnamese). 2023-04-24. Retrieved 2023-04-25.
- ^ "Relocation of endangered Chinese turtle may save species". Newswise. Retrieved on June 30, 2008.
- ^ "World's Largest Freshwater Turtle Nearly Extinct". News.nationalgeographic.com. 2013-07-01. Archived from the original on July 7, 2013. Retrieved 2014-06-16.
- ^ "New individual of world's rarest turtle found in Hanoi". Retrieved 2018-04-16.
- ISBN 978-1-4214-0135-5. (Rafetus swinhoei, pp. 258-259).
- Annals and Magazine of Natural History, Fourth Series 12: 156-161 + Plate V. (Oscaria swinhoei, new species, pp. 157-158 + Plate V).
- ^ a b "Rafetus swinhoei ". In: Fritz, Uwe; Havaš, Peter (2007). Checklist of Chelonians of the World Archived 2011-06-23 at the Wayback Machine, p. 182.
- ^ Le, Tran Binh. "COMPARATIVE MORPHOLOGICAL AND DNA ANALYSIS OF SPECIMENS OF GIANT FRESHWATER SOFT-SHELLED TURTLE IN VIETNAM RELATED TO HOAN KIEM TURTLE" (PDF). Retrieved 17 February 2012.
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- ^ "红河干流梯级综合规划报告通过评审". Yunnan Channel, Xinhua Net. 2003-04-04. Archived from the original on 2009-02-12. Retrieved 2008-09-10.
- ^ "Rare elderly turtles fail to produce offspring". NBC News. 2008. Retrieved 2023-12-21.
- ^ "Workshop on Rafetus Conservation in the Honghe (Red River) Drainage Area". Asian Turtle News. 2008-05-30. Retrieved 2008-09-10.
- ^ Moore, Malcolm (2008-10-06). "Bid to save world's rarest turtles fails". The Daily Telegraph. London. Archived from the original on 2008-10-07. Retrieved 2010-05-22.
- ^ "Attempt to breed Rafetus in captivity ends in disappointment". Turtle Survival Alliance. 2008-10-01. Archived from the original on 2009-06-14.
- ISSN 0362-4331. Retrieved 2008-10-09.
- ^ a b "World's Last Yangtze Turtle Pair Fails to Reproduce, Again". EcoWorldly. 2009-10-15. Retrieved 2009-12-03.
- ^ Artificial insemination New York Times, Retrieved May 25. 2015
- ^ "First Artificial Breeding Attempt for World's Rarest Turtle Unsuccessful". 2015-07-22.
- ^ "There Are Only 3 of These Turtles Left on Earth". 2017-05-23. Archived from the original on May 23, 2017. Retrieved 2017-06-02.
- ^ "Interview surveys in northern Vietnam look for remaining Swinhoe's softshell turtles in the wild". www.asianturtleprogram.org. Retrieved 2019-04-15.
- ^ "Population of world's rarest giant turtle rises to 4 with new discovery". news.mongabay.com. 2018-04-13. Retrieved 2018-04-16.
- ^ "More than one individual of Swinhoe's Softshell Turtle living in Dong Mo lake?". www.asianturtleprogram.org. Retrieved 2019-04-15.
- ^ "The hunt for the Madushan Monster". www.chinadialogue.net. 26 June 2017. Retrieved 2019-04-18.
- ^ a b "The Yangtze Softshell Turtle – TURTLE ISLAND". 2019-04-18. Archived from the original on 2019-04-18. Retrieved 2023-11-08.
Further reading
- IUCNPublications.
- Meylan PA, Webb RG (1988). "Rafetus swinhoei (Gray) 1873, a valid species of living soft-shelled turtle (family Trionychidae) from China". Journal of Herpetology 22: 118–119.
External links
- China's Turtles, Emblems of a Crisis - The New York Times
- Species: Rafetus swinhoei - Asian Turtle Conservation Network
- Video: The Loneliest Animals - "The Last Living Pair of Rafetus Turtles" - PBS
- Kolbert, Elizabeth (2019-05-20). "Climate Change and the New Age of Extinction". The New Yorker. Retrieved 2019-05-13.
- Rafetus swinhoei - IUCN Red List of Threatened Species
- In Search of Rafetus swinhoei - Turtle Conservation Vietnam
- It's love or bust for Yangtze turtles - The Observer
- Picture th:ภาพ:Rafetus thanh hoar.jpg