Rafetus swinhoei

Rafetus swinhoei, commonly known as the Shanghai soft-shell turtle, Yangtze giant soft-shell turtle , or Swinhoe's soft-shell turtle, is a species of soft-shell turtle. It may be the largest fresh water turtle in the world. It is listed as critically endangered in the IUCN Red List 2006, and is one of the rarest turtles in the world. There are only two known to survive in China: an 80-year-old female in Changsha Zoo and a 100-year-old male in Suzhou Zoo. In Vietnam, a single large individual lives in Hoan Kiem Lake in the center of Hanoi. In 2007, scientists conducting surveys west of Hanoi discovered the world's only living example of ''Rafetus swinhoei'' in the wild.

Distribution

''Rafetus swinhoei'' have been known to inhabit the Yangtze River and Lake Taihu, situated on the border of Jiangsu and Zhejiang provinces, in eastern China; Gejiu, Yuanyang, Jianshui and Honghe in Yunnan province in southern China; and the in the north of Vietnam. In recent years a single specimen of ''Rafetus swinhoei'' was caught by fishermen in Hoa Binh Province on the tributary of the .
The last known specimen caught in the wild in China was in 1998 in the Red River between Yuanyang and Jianshui ; that turtle was then released. A turtle in Hoan Kiem Lake in the center of Hanoi, Vietnam, has been sighted and caught on film in recent years.

Some local scientists claim that the specimen in Hoan Kiem Lake in Hanoi, Vietnam, is a separate species named ''Rafetus leloii'', or Hoan Kiem Turtle.

There are only two known living specimens in China, one each at Suzhou and Changsha Zoos. A third living specimen is at Hoan Kiem Lake;
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.
Another was recently discovered in a north Vietnam lake, according to scientists. This specimen is said to still be in the lake.

Cordinated by the Wildlife Conservation Society and the Turtle Survival Alliance, the still reproductive, more than 80-year-old female living in the Changsha Zoo was introduced to the only known male in China, a more than 100-year-old individual living more than 600 miles away at the Suzhou Zoo, On May 5, 2008. The female has arrived safely and settled in well into her new habitat at the Suzhou Zoo, and biologists were optimistic for breeding success.

Description

''Rafetus swinhoei'' are noted for their deep head with pig-like snout and eyes placed. They measure over 100  cm in length and 70 cm in width and weigh approximately of 120-140 kg. Their carapace, or shell can grow larger than 50 cm in length and width. Their heads can measure over 20 cm in length and 10 cm in width. Males are generally smaller than females and have longer, larger tails.

Reproduction

Individuals lay from 60 to more than 100 eggs. They nest at night and during the morning.

Diet

Includes fish, crabs, snails, water hyacinth, frogs, and .

Key threats

Rafetus swinhoei is on the brink of extinction due to habitat loss, hunting for subsistence and local consumption, and the use of the carapace and bones in medicine. Skulls are often kept as trophies. A recent plan to build hydropower cascade of 12 dams on the Red River in China may flood all of its habitat and change the ecosystem of lower Viet Nam

Conservation efforts

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. The two specimens were able to produce two clutches of eggs with over half of them being fertile, though unfortunately all of them perished before hatching. 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." . The two turtle are now being 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 are preparing to mate the two once again in May 2009, which falls within this species' breeding season.

The legend of Kim Qui

The specimen located in Hoan Kiem Lake in Hanoi is thought to be the legendary ''Kim Qui'' , or Golden Turtle God, who has appeared at opportune moments throughout Vietnamese history. The golden turtle first appeared during the reign of King An Duong Vuong and assisted the king in the construction of defenses for the ancient capital of . When Co Loa was attacked Kim Qui assisted the king in making a magical cross-bow that rained arrows upon the invaders. When the King’s daughter conspired against her father Kim Qui emerged again to inform An Duong Vuong of the betrayal; the king consequentially killed his daughter and drowned himself in the lake.

In the 15th century, a general named Lê L?i obtained a magical sword that a fisherman had pulled out of the lake. Lê L?i used this sword to lead a rebellion against the Chinese armies that were in occupation of Vietnam. After establishing Vietnam's independence the now King Lê L?i returned to the lake and Kim Qui caught the sword in his teeth and submerged. Lê L?i then named the lake 'Lake of Restored Sword', or Hoan Kiem.

In 1999, 2000, and 2005 turtles have reemerged from Hoan Kiem Lake on special occasions, when it was seen by a large audience and caught on film. It is believed that there is only a single turtle left in the lake.