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INFO/LITERATUUR/BOEKEN/ARTIKELS => TURTLENEWS => Topic gestart door: schildpaddennetcrew op 14 November 2008, 05:31:01



Titel: It's love or bust for Yangtze turtles (Caroline Davies)
Bericht door: schildpaddennetcrew op 14 November 2008, 05:31:01
THE GUARDIAN (London, UK) 01 June 08 It's love or bust for Yangtze turtles (Caroline Davies)
He nudged her gently. She nuzzled him back. And, almost as one, the dozen herpetologists, vets, conservationists and zoo officials who were gathered around the enclosure let out a sigh of relief.
He may be 100 years old and she a sprightly 80, but all hope for one of the most critically endangered species on the planet, the Yangtze giant soft-shell turtle, is vested in them. Nature must take its course and, say scientists, the first signs are more than encouraging.
Only four Yangtze turtles are known to exist. Three are male - one in a zoo in Suzhou in China's Jiangsu province, one in Vietnam's famous Hoan Kiem lake in Hanoi, and another in the wild in a lake east of Hanoi.
Until recently there was no known female. Barring a miracle, the species was to die out, mirroring the destiny of Lonesome George, the sole survivor of the Galápagos's Pinta Island tortoises. So the US-based Wildlife Conservation Society sent urgent circulars to every zoo in China asking for information on large turtles. It seemed futile. Repeated searches have yielded no others in the wild and the few specimens recorded in captivity were male, or had died.
Then Changsha Zoo in Hunan province responded. It had a turtle, but had no idea what kind. It had been bought from a travelling circus about 50 years earlier and had spent the past half century alone and largely unnoticed in a man-made pond.
With its stained, leathery shell, it attracted little interest among visitors to the rundown zoo. But its pig-like snout and wide, flattened dorsal shell resembled the photograph on the conservation society circular. Experts rushed to Changsha. Not only was it indeed a Yangtze turtle, but it was female and, though no teenager, she was still fertile.
'Can you imagine the excitement?' asked Paul Calle, the society's director of zoological health. 'There's four left in the world and only one of them is female. You can't get much more endangered than that without being hopeless. You can't get more critical.'
Today China Girl, as she has been affectionately named, is in a specially adapted enclosure 600 miles away at Suzhou Zoo, where she is becoming acquainted with her centenarian suitor. She was moved three weeks ago and almost immediately the pair began preliminary breeding activities. Bearing in mind that neither had seen another of their own kind for many decades, and that males can be particularly aggressive when breeding, it has gone better than could have been hoped for.
The zoo's pool was divided into three sections, she on one side, he on the other, with the middle empty. On the second day he was moved into the middle section and swam towards her. 'They saw each other and began sniffing each other through the grate,' said Rick Hudson, from the Turtle Survival Alliance. 'The day after that the grate was completely removed. The male was following the female when she moved, then she would move away and then come back to him. It was kind of flirtatious.
'We had mounting attempts within a couple of days - and it's still going on,' he said. 'We were worried. We didn't know when either of them last saw another one of their species. The male has got severe battle scars from a fight, but that was a long time ago. So he probably hasn't seen another turtle in 50 years. And she's been in captivity for probably longer than 60 years.
'We're all really tense. But we feel like we are making history here. This is really something. It's a remarkable event with new hope for a species that was getting ready to blink out on us.'
No one knows how long Yangtze turtles live, but China Girl had been producing unfertilised eggs. Ultrasound examinations proved she was still fertile. The Chinese initially wanted to perform artificial insemination, but no technique has yet been developed and turtles have died following the procedure. 'I don't think this would have been a good pair to experiment on,' said Calle.
So, eventually, it was decided to do it the old-fashioned way. Leading turtle expert Gerald Kuchling, an Austrian living in Australia, monitored China Girl's reproductive cycle and determined this month as the optimum time. 'If it all continues to go well over the next few weeks, she will lay eggs,' said Calle.
Much of the reptile's gradual demise has been attributed to the sale of the meat, bones and shells, partly for traditional Chinese medicine.
'It can't get more desperate than this.' said Hudson. 'This truly is the last gasp of a species and the risk we took is considerable. But the consequences of not doing anything was much worse.'
http://www.guardian.co.uk/environment/2008/jun/01/endangeredspecies.animalbehaviour