Transcript for Are sharks as dangerous as we think?
Reporter: It's every beachgoer's worst nightmare, coming face-to-face with the worst predator. Now terrifying headlines across the globe. One killed in Hawaii. The 65-year-old grandfather was swimming about 60 yards from shore when he was viciously mauled. Three bitten in North Carolina. I was like dad, please help me. Is she awake and breathing? If she is, she's barely. She's in bad shape. Reporter: A young woman tragically killed in the Jordan was fatally attacked. Her mother feet away from her in the water. Reporter: And this haunting green image captured by a father. The kids were standing in the water. And I'm like, get out, get out, get out. I was like ripping him out of the water and trying to get limb out of the water when my mom was telling us to get out. Reporter: The power of sharks has long terrified and fascinated people. But for Jeremiah Sullivan, his decades-long study of sharks has led him on a quest to get even closer, his work documented in TV shows. Oh, that was a close one! You have to figure out a way to work with sharks without disrupting their natural behaviors, and a cage in the water or safety divers or a bunch of other people tend to alter the behavior of the animals. Reporter: He created a shark suit, a protective armor allowing him to study them without cages. How did the suit evolve? The majority of sharks responsible for bites on humans are less than nine feet. These are reports when I was a young biology student. I'm thinking, okay, fine, we'll fix the worst problem. Let's take care of that. Exposing people safely to these kinds of animals in the right-structured circumstances and with the right information I think is a wonderful way to expose people to other creatures that we share the sea with. Reporter: But so far his suits haven't been foolproof, unable to withstand the biggest of shark bites. Now he's putting his latest id rags to the test. We make them in titanium and various other things. When you're making chum, frequently, the shark's sides are silvery. If you have a piece of fish in your hand it looks very similar to the hand. If he's coming in for the fish he could chew on you. Reporter: I will never wear a silver bathing suit again. Reporter: After meeting Jeremiah, I got up close and personal with sharks at the long Island aquarium, protected by a cage. Most people never get this close to sharks. And the reality shark bites are even rarer. You're about 30 times more likely to be struck by lightning and killed than you are to be bitten by a shark. You're about 100 times more likely to get in a car accident and get injured on your way to the beach. So shark bites are incredibly rare events. Reporter: Gavin is among the leading shark experts. His team set out to tag deep-water sharks. If we look over the long decadal trends we see there is a very slight increase over the last 50 years. And we believe this is largely because there are a lot more people pursuing recreational watersports. However, two years ago, we saw a substantial dip in the number of shark bites globally. Oh! Wow! Reporter: He says we have an irrational fear of sharks, cultivated over the years by popular culture with films like "Jaws" defining our image of the animals for generations. Shark bites are horrific events, and they're tragic it creates this wave of angst that spreads throughout the local population. And it is, it's very violent and traumatic but a lot of things in nature are. Reporter: Something Paige winter knows all too well. The 17-year-old told her story to my colleague, robin Roberts just days after she was attacked off the coast of North Carolina. How far away from shore were you? The deepest I got was waist-deep. Reporter: She was swimming off atlantic beach with her family when the shark attacked. Sometimes you go to the beach with your family and they grab your leg as a joke. And I was like, ha, ha, really funny, ow. I start feeling around and I feel it. I go from front to back, is this a snapping turtle? What's happening. You know how a dog, they get a rope and you grab the other end of the rope and they start going with their whole body. Reporter: She lost most of her left leg and sustained damage to both of her hands. I told her I was going to have to amputate her leg, and she said okay can I get a cool prosthetic? You can get whatever you want. Reporter: Paige doesn't blame the shark. This situation has urged me to learn more about sharks. Because even in the back of that ambulance, I was like, don't get mad at the shark. I'm like, the shark is fine. Can you help people understand why you feel that way? I've always liked animals more than I've liked people, you know. I think they don't do anything to people unless people do something to them. And, you know, I didn't do something directly to the shark. But I was in his water, you know. That's his house. Reporter: She's using the experience to raise awareness about the impact humans have on sharks. I love sharks. And let me tell you, 11,000 sharks are killed an hour. 97 million sharks are killed a Reporter: Most of the world's shark populations are in decline as a result of overfishing and habitat loss. It's estimated maybe a quarter of all shark species are threatened. With extinction. By contrast, there are perhaps on average six people that are killed at the hands of sharks every year. Reporter: These days, mainl is undergoing therapy to learn to walk in her new prosthetic leg. I was aware from the beginning, nothing's ever going to be the same again. Like, I'm still paigy, just a little different. I've got some pieces of the puzzle missing. But that's okay. The shark didn't touch your spirit. It did not. Reporter: For "Nightline," I'm Diane Macedo. You can catch Jeremiah Sullivan checking out his suit in "Man versus shark" during shark fest on nat geo. Up next, the man with moves
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