Giant Catfish May Be World's Largest Freshwater Fish

Thai fisheries officials had hoped to release this adult female Mekong giant catfish after they stripped it of eggs (above) for a captive-breeding program. But the whopping fish, which was as big a grizzly bear, didn't survive.

Listed a critically endangered by the World Conservation Union (IUCN), the Mekong giant catfish is one of the world's largest freshwater fishes. Other contenders include the Chinese paddlefish and the dog-eating catfish—another Mekong River giant.