The world's largest freshwater fish are losing the fight for survival, as pollution, overfishing, and construction threaten the rivers and lakes they call home.
So earlier this year ecologist Zeb Hogan launched the Megafishes Project, a three-year effort to document the 20-some species of freshwater fish at least 6.5 feet (2 meters) in length or 220 pounds (100 kilograms) in weight (profiles of the megafishes).
The project is designed not only to raise awareness of the animals' plight, but to highlight the increasingly dire situation of the world's water sources.
Join National Geographic News on the trail with Hogan as he tracks down and studies these real-life "Loch Ness monsters": leviathans such as the Mekong giant catfish, the giant freshwater stingray, the arapaima, and the Chinese paddlefish.
(The Megafishes project is funded by the National Geographic Society, which owns National Geographic News.)
| || || Part Five: World's Largest Shark Species at Risk, Expert Says (January 17, 2008)|
Whale sharks are coming under pressure from overfishing and habitat degradation, putting the world's biggest fish in urgent need of protection, says biologist Zeb Hogan.
| || || Part Seven: Giant River Stingrays Found Near Thai City (April 29, 2008)|
Fourteen-foot-long rays—perhaps the largest freshwater fish—are thriving not far from Bangkok. But overfishing may still threaten the giants.
| || || Part Nine: Giant Prehistoric Fish Rebounding in Canada (November 13, 2008)|
The white sturgeon, North America's largest freshwater fish, has bounced back in the Fraser River thanks to an unprecedented volunteer effort including fishermen and aboriginal groups.
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