Shark Files: How Did 'Deep Blue' Get So Big?

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Great white sharks are the biggest predatory fish in the world.


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Close Encounter With a Great White Shark: Photos

Great white sharks are the biggest predatory fish in the world. And despite their mass, they can travel at ridiculous speeds, at over 35 miles per hour, to track their prey. Marine biologist Joe Butler traveled with two friends off Hans Bay, South Africa, in hopes of seeing some great whites. Which they did. See more of Butler's story on a new episode of This Happened Here on the Seeker Network. Shark Files: Shark Bite Risk Down 91 Percent Since 1950

Joe Butler

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"In order to bring them in closer, to give everyone a good look, the crew would employ a tuna head on the end of a long rope and drag it out of the way before the shark had a chance to grab it," Butler said. Shark Files: Great White Shark Photobombs Friend

Joe Butler

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This amazing photo, taken from inside the cage, shows the shark grabbing the bait before anyone had a chance to react. "There's actually quite a sobering moment when you realize that proverbially you're the fish out of water, this is their home, and you’re not actually supposed to be there," Butler said. Shark 'Highways' Crisscross The World: Photos

Joe Butler

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"I think a lot people have this image in their head of them being sort of an idealistic predator, but in reality these animals are still quite vulnerable. However, seeing them in their natural environment is something I would recommend to anyone in a heartbeat." Above, Butler (left), prepares to cage dive with his two classmates. Shark Files: Scary Footage Shows 15-Ft Great White In Mass.

Joe Butler

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A marine scientist is dwarfed by what is being called the biggest shark ever caught on camera in a recent video taken near Mexico's Guadalupe Island. How did this 20-foot-long (6 meters) great white Internet sensation become such a behemoth?

How does a multi-ton shark come flying up out of the water in such dramatic fashion?

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Named Deep Blue, the female shark made a colossal impression in video clips shared on Facebook by shark researcher Mauricio Hoyos Padilla, director of Pelagios-Kakunjá A.C., a nonprofit organization that focuses on sharks and other open-water species. Underwater footage shows Deep Blue circling a shark cageholding Padilla and other divers. ( Another video of this huge sharkshowed the animal giving what some called a "high five" to cage divers.)

Even though great white females are typically larger than males, they average just 15 to 16 feet (just under 5 m) in length. Deep Blue's exceptional size, it turns out, is probably a combination of genetics and environment, experts say. [ See Stunning Images of Great White Sharks]

Great white sharks need decades to reach adult size, and they continue to grow throughout their lifetimes. So, a much-bigger-than-average shark, like Deep Blue, is likely an older shark.

In fact, Gregory Skomal, a fisheries biologist at the Massachusetts Division of Marine Fisheries, and his colleagues found great whites grow even more slowlythan scientists had thought: The biologists' research, published in January in the journal Marine and Freshwater Research, suggested males take 26 years to reach sexual maturity, whereas females aren't ready to have babies until they're about 33 years old — much later than once thought. That study also showed that great whitescould live to be at least 73.

Padilla estimated that Deep Blue was about 50 years old, based on her size. Skomal's study hints that there may be much older sharks than Deep Blue out there, and they could be even bigger.

After reaching maturity, white sharks' growth slows — but it doesn’t stop.