Yes, Tridacna clams are CITES listed - as CITES II which means the trade is
regulated (you cannot go out and collect them but a commercial operator with
the proper license can collect, grow, and sell them) and they have been
commercially grown for well over a decade and are harvested for the tourist
trade (locally), meat, and the aquarium trade.  They have grown them long
enough that decent sized shells have been offered.

Tom Eichhorst
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