The ocean, a vast and mysterious place, covers approximately 71 percent of our planet. But did you know our seas and waterways are home to some of the oddest creatures in the world? Sea monsters have fascinated authors—not to mention sailors!—and tales abound about the Kraken, mermaids, and underwater lights. In modern society, these and many others, can be scientifically explained and many just might be the active imagination of seafaring men from long ago who saw the things that Zeb Hogan has seen in National Geographic’s Monster Fish.

Part myth buster, part educator, the Arizona native travels the globe with his crew in search of giant species of fish. Most of the fish Zeb searches for are rare, elusive, and more often than not, endangered but it’s his mission to document their existence to ensure their survival, as well as increase awareness of the importance of clean, healthy waters. Below is only a sampling of the nightmare, exotic and bizarre giant fish you’ll see as Zeb and his crew, together with local fishermen and other scientists and marine biologists, reveal the amazing and sometimes startling creatures that inhabit our planet. And who knows? Perhaps some of these giants are what have inspired the fictional sea monsters we’ve read about, adding to the mysteries of the deep, in Monster Fish.

25 The Ocellate River Ray

While looking for the short-tailed river ray, Zeb Hogan and fishing guide Mark Jones find an ocellate river stingray in the Paraná River in Argentina. The Paraná, the second longest river in South America, after the Amazon, is home to 6 different species of stingrays. With a thick, powerful tail, the ocellate is responsible for most of the accidents that occur on that river, releasing a toxin that’s more powerful than that of other rays. However, scientists believe the ocellate lashes out when it feels threatened as opposed to being an aggressive predator.

24 Demolition Derby

When Zeb Hogan, host of Monster Fish and fish biologist, isn’t filming with his crew, they partake in local events and enjoy eateries recommended by area natives. In this photo, welders, mechanics, and builders of “monster” cars pose after a demolition derby. The car was souped up special for the show and although it didn’t come out a winner, a good time was had by all. Zeb even was allowed to drive the car at this event that many say is exclusive to this particular area of the deep south.

23 Giant Wels Catfish

Zeb Hogan believes this giant wels catfish is the fish of a lifetime. Starting off in the small French town of Albi, in Southern France, Zeb observes catfish, normally a bottom dweller, feed in shallow water. Shaped like a supersized eel with a head like a massive balloon, the wels was reputed to grow up to 8 feet in length and weigh up to 200 pounds. This particular wels, captured in the wee hours of morning, is 8 feet long, weighs well over 200 pounds and took three men to lift the fish out of the water.

22 Giant Freshwater Stingray

After receiving reports of a giant freshwater stingray, Zeb Hogan and the crew of Monster Fish head to Nakhon Sawan province and then to the Mae Klong River in Central Thailand. They capture, measure, and weigh a stingray that is 14 feet long and comes in at just under 370 pounds, similar to the one shown here. However, experts believe that giant freshwater stingrays can weigh more than 1000 pounds. But documenting such exotic fish is tricky and dangerous due to the barbs in their tails, which can be toxic.

21 The Goliath Grouper - Misunderstood Giant

Zeb Hogan dives with one of the biggest Goliath groupers he’s ever seen and finds the fish is by-and-large misunderstood. Though some claim it’s a monster fish predator, nothing could be further from the truth. They tend to feed on sea creatures at the bottom of the food chain, attacking near the surface, and at bigger fish, only because the fish sees it as an “easy meal.” This particular fish measure 7 feet in length and weighed approximately 300 pounds and was found near a shipwreck off the coast of southwest Florida.

20 Amazon Redtail Catfish

In Thailand, searching for an endangered giant carp, Monster Fish host and fish biologist Zeb Hogan catches another nightmare fish in the Mekong River, which also flows from Thailand and into Cambodia. This time Zeb has caught an Amazon Redtail Catfish, a fish which can grow up to 100 pounds. Recognizable by the light belly, dark back and bright red tail, the specimen photographed with Zeb comes in at 30 pounds, is exotic to the area, and released before host and crew continue on their quest for giant carp.

19 Amazon Swamp Eel

While in the Amazon, searching for an elusive freshwater eel that reputedly shocks a person five times stronger than an electric socket, Zeb Hogan and the crew of Monster Fish need to tread carefully. From Manaus to the Purus River in Capichauã, Zeb ensured they were in wood boats, instead of metal, or they could be shocked. Especially when having to jump into the river. And remember that the larger the eel, the larger the shock. Luckily, the swamp eel in this photo was perhaps the only one they came across that doesn’t shock.

18 Noodling In Chattanooga, Tennessee

After many hours in the water, local fishermen in Chattanooga, Tennessee show off a large catfish, with Zeb Hogan and the crew of Monster Fish. Here Zeb has learned firsthand about a Southern style of fishing they call noodling. It’s an extremely difficult thing to do, time-consuming, and not to be done without work gloves to protect hands and skin. Noodling, as Zen learned, consists of sticking his hands into holes at the shallow end of a river, in order to catch fish without a net.

17 Silver King Tarpon

After exploring Lake Nicaragua, a lake the locals call the freshwater sea, Zeb Hogan and the crew of Monster Fish search for a 300-pound giant tarpon. Normally found at sea, this particular tarpon can be found in freshwater but heads to salt water in order breed. From Lake Nicaragua, Zeb, his crew, and local fishermen trek through the San Juan River to the Caribbean Sea, all to tag and witness a tarpon so large it can take hours to land the fish, even for the most experienced of fishermen.

16 Elusive Speartooth Shark

Together with Dion Wedd, Curator at Territory Wildlife Park, Zeb Hogan finds something rare and elusive, and exactly what he was on a quest to find. This small shark is between 1 and 2 years of age and is about three feet long. When fully adult, they are usually between 7 and 10 feet and can be identified by narrow, spear-like teeth, black tips on their fins, and the change in color from gray to white, almost at the same line of their very small eyes. This particular shark was captured and put on display at the aquarium in order to document behavior patterns.

15 Kicking Back And Chilling

Zeb Hogan is more than just host of National Geographic’s Monster Fish. And he’s much more than a biologist! This Arizona native is eager and excited to talk about fish. The show takes up a good portion of his time and when he and his crew are out filming, it’s non-stop. However, that doesn’t mean they don’t get to appreciate their surroundings. And what better way to get to know the locals than by kicking back and chilling between episodes? It’s the best way to find out about the expert fishermen living in the area that might be able to help out and be part of the show.

14 BTS Of Monster Fish In Chattanooga, Tennessee

While hosting and filming Monster Fish, sometimes there’s plenty of time to socialize. Here, while on a quest to find a monster catfish that is the stuff of local legend the size of a car, Zeb Hogan poses with local fishermen and his crew before filming their next segment. Shown here, in Chattanooga, Tennessee. Zeb poses along the river bank with fellow fishermen, and crew of Monster Fish, before filming the next segment, where they will all learn about a mostly Southern form of fishing called noodling.

13 Vampire Fish

One of the exciting things about going fishing for a specific type of monster fish is that Zeb Hogan and his crew never quite know what they’re going to find. In this instance, while fishing the Essequibo River in Guyana, Zeb comes across the Vampire fish, aggressive, acrobatic fish that can launch itself several feet out of the water. With the longest teeth on any fish in the world, it’s no wonder how it got its name or why one must be careful when capturing this exotic creature.

12 Wolffish

Known locally as Haimara, Zeb Hogan holds up a wolffish. This specific exotic predator was caught at night, when it’s known to feed, with the help of fishermen from the Wai Wai tribe, an indigenous group living between the border of Guyana and Brazil. The wolffish caught measures about 3.5 feet in length and weighs approximately 40 pounds. The species has the reputation of being the King of the river and is reputed to be even worse than the piranha. The elusive fish gets its name for its appearance and jagged teeth and is known as an ambush predator.

11 Swimming With Fish

What does Zeb Hogan do when he and his crew aren’t filming for Monster Fish? Why, promote, of course! But he doesn’t only talk about the wildly popular show he hosts. As an American biologist, specializing in fish, this Arizona native is all about the education and conservation of Earth’s most precious resource; the ocean. Shown here after a tour at the Tennessee aquarium, Zeb swims with sharks, stingrays and an entire assortment of more common, and some not so common, fish that grace our planet’s waterways.

10 Zeb Hogan - American Biologist

Zeb Hogan, an Arizona native, is an aquatic biologist and assistant professor at the University of Nevada. As host of Monster Fish, he and his crew get to travel the world, often to exotic, and at times out-of-reach places, where some of the giant fish are endangered. Zeb also enjoys speaking with people about the importance of fresh water, rainforest, and coral reef conservation. Protecting critically endangered fish, Zeb says, as well as the livelihood of people who live off what the catch, is crucial to healthy freshwater biodiversity. Shown here, he kicks off the Masterclass for Continental Trout Conservation Fund.

9 The Goliath Grouper - A Gentle Giant

Despite its size, the Goliath Grouper is more curious than aggressive, especially when it comes to people. They tend to aggregate in relatively shallow water, preferring to remain near small reefs or shipwrecks. Once over-fished, experts believe they may be making a comeback. They are protected and one of the largest bony fish on earth, growing up to 8 feet in length and weighing in at over 600 pounds. They are recognizable for their big head, thick lips, a large mouth, and mottled color.

8 Between Zeb Hogan And The Sea

Filming and hosting for National Geographic’s Monster Fish can be an exhilarating rush of adrenaline, especially when searching for bull sharks. But as Zeb Hogan himself has said, there can often be plenty of downtime in between production. So, while Zeb and his crew wait for the fishermen on the boat to trawl for shark bait, the Arizona native takes a break from his duties and smiles for the camera while on a boat in the Jupiter Inlet, just off the coast of Florida.

7 A Moment With The Captain

A fishing expedition is never an easy task. It takes a concerted effort and a group of dedicated professionals to pull one off, especially when it involves shark fishing. But just as important as crew, the captain of the boat is essential. Here, one of two captains, from one of two ships, takes a moment to relax with Zeb Hogan, who snapped this picture during a bit of downtime. Their mission to search for a bull shark to capture, tag and release, was successful, allowing them to determine why so many Floridians have encountered the aggressive ocean predator in freshwater when they usually swim in saltwater.

6 Sharing A Laugh With Zeb

Behind the scenes of Monster Fish, on site in Florida, Arizona native and American biologist Zeb Hogan shares a laugh with Arianne, during some downtime on the Caloosahatchee River. The fellow biologist is a member of Professor Jim Gelsleichter’s crew, from the University of North Florida, who all joined Zeb and his show crew in search of the wildly aggressive bull shark. Together, they went fishing for a bull shark and were able to capture and tag a baby shark in order to track growth and migrations patterns.