WASHINGTON -- Most people run away from monsters, but not Zeb Hogan.
The host of National Geographic's "Monster Fish" has made a career our of unearthing some of the planet's most terrifying, if misunderstood, aquatic creatures.
"I've had a project the last 10 years or so to find, study and protect the world largest freshwater fish," Hogan says.
This sounds like a noble cause, but consider what kinds of fish he's huntng. They are generally longer than 6 feet and weigh more than 200 pounds. Hogan's research has taken him all over the world, from Southeast Asia to South America and even to the backdoor of some local neighborhoods.
Bullsharks, invasive snakehead fish and giant Atlantic sturgeon are among the unusual species found in the waters of the Potomac River. In fact, the world record for one species of snakehead was caught locally last year. The beast weighed more than 17 pounds and was nicknamed the "Frankenfish" because of its ugly mug.
"They're from Asia and they're not supposed to be in the Potomac," Hogan says of the fish. "But now that they're there, they are getting big."
A marine biologist and University of Nevada professor by trade, Hogan does not recommend that anglers or lay fishermen go out and seek these river monsters. If you happen to encounter one, however, "the best thing to do is respect the fish as the large potentially dangerous creature it is," he says.
"They're not a threat to humans and, actually, we pose much more of a threat to the fish than they pose to us," Hogan says.
About 70 percent of the fish he hunts are verging on the brink of extinction, Hogan says.
The Arizona native developed a passion for studying these creatures at an early age, but it wasn't until his college years that Hogan was able to fully explore them.
As an undergrad, Hogan surveyed endangered fish in the Grand Canyon's Colorado River and then spent time in Thailand, which happens to be home to more species of giant freshwater fish than anywhere else in the world.
"That got me thinking, 'Are there big fish like this in other places?'"
The answer turned out to be yes. There are roughly two dozen species of giant freshwater fish in rivers and lakes around the world: the Nile in Egypt; the Danube in Europe; the Mississippi in North America; the Amazon in South America and so on.
On his show, Hogan and his team travel the globe in search of these creatures. He links up with local scientists, fisherman and residents familiar with the fish.
Of all the towns and countries he has visited, Hogan says northern Australia with its red rocks and massive canyons stands our from the rest. The region reminds Hogan of his native Arizona, but there is one very big difference.
"You get this desert feel, but the rivers in northern Australia are home to three species of freshwater sharks, a giant species of freshwater stingray and a couple species of freshwater sawfish, which can get to over 20 feet long," he says.
With so many strange and unusual animals from which to choose, Hogan says picking a favorite can be hard. In fact, each new fish he encounters becomes a current favorite. He is partial to the giant stingray, however, which tends to be friendly and curious when it comes to humans.
"They're not shy. I was able to get in the water with the stingray and they just kind of sit there and check me out."
Despite its amiable nature, they can be dangerous. The stingray's barb is sharp and can be used as a defense mechanism.
Hogan says he has mostly been lucky and avoided injury, but not necessarily his crew.
One camera man was shocked by an electric eel, capable of producing a shock up to 700 volts, or fives times what comes out of a wall socket, Hogan says. And a different member of the crew was bitten by a shark just this year.
"We were quickly handling the shark to get it back in the water and the (shark) just turned up and got his hand," Hogan. "It was just unlucky."
"Monster Fish" airs Mondays at 9 p.m. on Nat Geo WILD. Click here for an episode guide.
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