Giant fishes, including those said to have eaten dogs and cats, are to appear in a new television series on the National Geographic Channel.
The Monster Fish series, which is hosted by Zeb Hogan, the biologist working on the National Geographic Society and World Wildlife Fund MegaFishes project, offers a mix of "science, adventure and exploration".
Among the highlights are expeditions up the Amazon and the remote Rio Roosevelt, a 400-mile river in western Brazil, which is relatively unexplored by modern biologists.
The programme features introduced Asian carp, the Alligator gar, Wels, giant 600-pound Siamese carp, 10 foot long Mekong catfish and giant freshwater stingrays.
"Four of the shows focus on invasive species issues, where the giant fish are taking over new habitats", said Hogan.
"This series of shows focuses heavily on invasive-species issues, a critically important topic for the health of aquatic ecosystems like Lake Tahoe, the Mississippi River, and the Great Lakes.
"I'm alarmed by what I’ve learned. These carp put on several pounds each year, a phenomenal growth rate. They quickly outgrow any predators but humans. Native fish don't stand a chance against them; they can grow to almost 100 pounds."
The MegaFishes Project is described as the world's first attempt to document and protect the planet's freshwater giants.
Many of the world's largest fish species, including the Giant Mekong catfish, Pangasius gigas, the Giant Mekong stingray, Himantura chaophraya, as well as sturgeons and arapaima are "disappearing at an alarming rate."