From No Fish Tale: Thais Catch 646-Pound Fish:
Thai fishermen caught a 646-pound catfish believed to have been the world’s largest freshwater fish ever recorded, a researcher said Thursday.The 8.9 feet Mekong giant catfish was netted May 1 by villagers in Chiang Khong, a remote district in northern Thailand, and weighed by Thai fisheries department officials, said Zeb Hogan, who leads an international project to locate and study the world’s largest freshwater fish species.
He confirmed it was the heaviest recorded fish since Thailand started keeping records in 1981.
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The fishermen had hoped to sell the fish to environmental groups, which planned to release it to spawn upriver, but it died before it could be handed over, and was later chopped up and sold in pieces to villagers to be eaten.
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The Mekong giant catfish — which shares the title of largest freshwater fish with a close relative, the dog-eating catfish — was listed as endangered in 2003 after research showed its numbers had fallen by at least 80 percent over the past 13 years.