I wrote to a turtle conservation group in Bangkok and received the following email back:
"Dear Jeff, Unfortunately, what you've got is not a Mangrove terrapin. It is not even a native species. It is a Chinese Soft Shell Turtle (Pelodiscus sinensis). They have been introduced to Thailand as farmed animals, and they frequently escape from captivity. I suspect your sightings are of a small population that escaped from some farmer's ponds. Hope this helps. Sincerely, Bill"
Oh well, bit disappointed but so still a good find. I have been doing a little bit more research on the Chinese Softshell Turtle and they are classified vunerable on the IUCN Red List of Threatened Species. They are also mass bred for turtle soup.
Mentioned this to a friend of mine, (he's travelled the world a lot as he was in the Royal Navy some years back) and he said to me " Do you know how they deshell them?"
"No!" was my reply.
He said "They hang em up, and tie big weights to their neck and let them hang till they pop out" LOL...sick.
We keep finding terrapins all other the place, not sure what type but they are common, got some pics somewhere once I dig em out will post them. But the other month I had 3, one was quite big, used to keep them just outside in a water trough, anyway went to clean the trough out one day and the big one had gone. Some one had had it away.
About 2 months later I was having a drink with a swiss friend of mine, a taxi driver pulled up, he had a limp, and he came up to us, said to me your lady wan, nikhom, I said yes, he ment my lady is wan from Nikhom. He then asked me "Phuut Phaasaa Thai (speak Thai) I said " Nig Noi" (littlebit).
Asked my friend the same and he told him he understood and could speak thai. The taxi driver spoke to my friend, they both laughed and the taxi driver went and sat down with friends. I said to my friend what he say, he said he told me I had not to tell you. I said, what? . My friend said if I tell you you will get angry, I said I promise I will not get angry, so he then said that man as just said, "Farang's(forigner), turtle make good soup". I nearly fell off my chair laughing.
I couldn't believe it, I had never met this taxi driver in the 4 years I have been here, but he knew me, and he knew about the turtle disappearing. I starting to believe all Thais are related, cause they don't miss a thing.