>> jimmy: nick, thank you for being here. his book is called "paddle your own canoe" and it is coming out in october. i don't think we've ever bumped anybody besides matt damon. he is out. we ran out of time. thank you for watching. "nightline" is next. good night.

they're dangerous, ruthless, killing machines. on "nightline." the most dangerous predators. sharks. with attacks on the rise. these guys are looking for their next meal in shallow waters near you. >> whoa! >> we're going face to face. with the coolest fish on earth. >> did you see that? this special edition of

good evening, thanks for joining us. their ancestors likely swam our

oceans 400 million years ago. well before dinosaurs ever struftd on land. sharks, as ghastly as they are graceful, have proven to be the ultimate survivors. while much of their innate savagery occurs under cloudy seas, when it comes to attacks on humans they are high profile predators with just about every incident making international waves. these days it is not all hype. attacks on human have increased by over 30% in the last five years. in partnership with discovery network, sam champion dives in with these awe inspiring creatures to find out why. >> they're some of the most feared predators on the planet. with ferocious teeth and a bite from hell. you rarely see them coming. >> there is this massive sharks head attached to me. >> every so often a person comes eye to eye with a killer and

survives. >> i was swimming through a pool of my own blood and i thought i was dead. >> take a close look. that's paul being pulled un. >> could i see the lip pulled back. i could see the gum and the row of teeth all the way across my leg and over my list. >> a highly trained driver, he was off the coast in australia when a ten-foot bull shark shred through his arm and leg. >> all i could do was just flop around in the water while this monster was shaking me. my survival instincts kicked in. i thought i've seen steve irwin, i've seen discovery channel, i'll jab him in the eyeball. i cut back and i hit him once. that did nothing. and he started shaking me. that's when the pain really kicked in. there was a tearing the hamstring out of my leg and tearing my hand off. >> experts say shark attacks on humans have reached an all-time high. it has been one of the most

fatal years on record. >> to a scary start to shark season. >> the jaws are inside the cage. >> a great white shark has killed a young surfer. >> there were 80 cases of unprovoked shark attacks on human last year. ten years ago, just 60 attacks. in some parts of the world, there is an larling trend of sharks developing a fatal attraction to shallow waters. there are many species of sharks but research shows shark populations are declining. so why are attacks on the rise? some experts believe we could be to blame. they say humans have been destroying the oceans for decades. polluting the water, overfishing and taking away the food sharks normally eat. these are shark experts and stars of the discovery channel's sharkpocalypse. andy and devin have traveled the globe in search of these killers

to find out why there is a spike in shark attacks. so i went underwater with their team in the bahamas to get an upclose look at some of the oceans' eating machines. >> don't act like food, don't smell like food, don't be food. >> we head out to the atlantic for my first experience eye to eye with a shark. >> that's a school of sharks. >> a boat was immediately surrounded by nine-foot caribbean reef sharks all looking for lunch. >> i can't even count how many there are. >> there's more than a dozen. >> the sharks i'm facing today are normally shy around divers but they've been known to become aggressive while feeding. so for my first dive, the crew recommends i wear a chain metal shark suit for extra protection. it weighs over 20 pounds. >> got that feeling of safety. >> with this special mask, i can talk freely so you're on the

dive with me. >> look down. shark on your right. >> wow! to see them up close. it's unbelievable. i have to keep turning around and turning around. they're in all directions and you don't want to miss a minute. >> the experience was incredible. these reef sharks are not the ruthless killers i expected. >> it's beautiful. >> but if their food source continues to decline, experts say sharks may be forced to look for an easy meal elsewhere. >> for the decimation of sharks be creating a sharkpocalypse? >> check this out. >> the team from the show decided to conduct an experiment to test a shark's pal at. >> what do we have before us? >> this is a shark buffet. we've got fish, pork, beef links, turkey, even a vegan mel.

>> a 14-foot tiger shark comes in and goes straight for the barracuda. part of its normal diet. >> it's biting the pig in half! >> discovery channel expert say pork is the closest thing to human flesh. >> let's see if he goes for the turkey next. here it goes. taking the turkey. >> the lesson here, if you disrupt a sharg's viral, take away their fish, they'll feed on the next best thing. but what if there was a way for humans to repel sharks? dr. patrick rice is a scientist developing a special chemical to fend off these killers. >> how does it work? >> we discovered that the king shark tissue releases a death

pheromene. >> let's test it. >> to test it out in this dive, devin baits the reef shark into a feeding frenzy. >> there is a lot of sharks down here. >> the chemicals from a dead shark will chase them away. >> that was close. hey, devin. use the repellant now. >> watch what happens when the chemical is released. within seconds, the sharks disappear. >> absolutely nothing around. >> these experiments are important to better understand why these brutal attacks occur. and how to stop them. >> every time that i ever got into the water as a diver, i always spotted sharks instantly every single time. i was petrified of sharks. >> let's face it. the chances you'll be attacked by a shark, 1 in 11.5 million, to be exact. when they happen, they are

brutal. paul's shark attack lasted just eight seconds. >> shark continued to shake me basically like a dog with a rag doll. a big pink plume all around me. i was just focused on getting to that safety boat. that was all he wanted to do. swim as hard and fast as i cox. >> he lost both a hand and a leg that day. >> the shark basically removed all of my hand except for one finger, i think my enthusiasm was almost inside out. there was a bit of thumb meat. but that was it. there was nothing that could be salvaged. >> even if they don't mean for us to be their food, paul's experience is a testament to the sheer power of the ocean's natural predators. coming face to face with death didn't stop paul. he continues to dive regularly even with shark. >> i think everything fell into place for me. someone was smiling on me that

day. >> i'm sam champion, in nassau, bahamas. >> paul is a brave man as is sam champion. now, keep in mind while shark attacks are up, your chances of becoming a victim are still tiny. shark week airs each night on discovery channel. next, from jaws to deep blue sea. we can never seem to get enough of a good shark flick. could save you fifteen percent or more on car insurance. mmmhmmm...everybody knows that. well, did you know that old macdonald was a really bad speller? your word is...cow. cow. cow. c...o...w... ...e...i...e...i...o. [buzzer] dangnabbit. geico. fifteen minutes could save you...well, you know.

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. ever since the blockbuster

film "jaws" hit theaters and spawned nightmares in the 1970s, it seemed movies about sharks are a recipe for success at the box office will come on, this summer's made for tv film "sharknado" about man eating sharks taking over los angeles became a summer phenomenon. while these film can be good for the movie studios, they're almost always bad for the sharks. >> they are hollywood's most perfect villain. sleek and silent. fascinating and fanning our deepest fears. great fun for us and guaranteed to sell tickets. but what about the sharks? >> these films depict them as ferocious, mutilating, thuggish monsters. that is bad for sharks. >> really bad. we kill something like 100 million sharks a year for soup.

the chance that you'll become a shark's meal, less than 1 in 264.1 million. >> the downside of these depictions of sharks in popular films where sharks are shown as being monsters, the down side is that the public then believes they are not worth saving. >> so what makes these movie monsters so mesmerizing? >> they're almost a perfect story telling engine. they just want to eat you and you have to get away from them and that's terrifying. >> think back to when they were making the granddaddy of all shark movies as seen here in the making of "jaws." and think of the star. he did not need make-up. he work for free. he always knew his lines, chomp, chomp. the shark in "jaws," 1975. he was really the perfect performer. except for the occasional mechanical problem in the water. but in the story, he was the

perfect villain. >> just the sheer fact that they're so relentless, the way they look with those jinlt rows of teeth. it is ridiculous. it makes you laugh. it makes you smile a little bit. the combination is really perfect for a very specific kind of genre movie. >> you want a bad guy? here's a bad guy. you want character development? well, maybe sharks aren't quite right for that. there's no real motivation to a shark. in the movies, other than i want your leg in my mouth right now. >> right. that's why in the deep, 1977, you basically feel you already know that shark. so shark as character, good for movie makers. without trying to be too exact about it, we counted up more than 50 shark movies in the spirit of "jaws" made since 1975

in which the shark represents evil. how many movies were made with shark as the good guy? again, not an exact accounting but it looks like almost none. even in identifieding nemo made by our parent company, walt disney, the shark was scary, although the joke was that they realized they needed to try to be nicer. >> i am a nice shark. not a mindless eating machine. >> we had to be far more scared for sharks, not of sharks. >> that's not how it goes. rather all the changes in the typical shark movie is the shark's meal. in jersey shore shark attack. >> they're everywhere! >> the entire city of los angeles in "sharknado" where sharks fly.

and speaking of sharks in weird settings, we've had sharks in weird unnatural configurations like shark-topus. a big shark with octopus legs. >> okay. you can do anything you want with it. you can go very serious and scary like "jaws" or you can have a borderline movie like deep blue sea. >> that's the one where the sharks become intelligence. let's take that back about no character development. hold it, stop this, freeze this. okay. let's roll the shark documentary. now, this is. closer to reality. to the truthful in the documentary called shark mountain. many such films show real respect. ah, but respect. does that sell tickets? for "nightline" in washington. >> interesting fact, six years

before stephen spielberg's "jaws," burt rernlds shot shark. it gives you a special appreciation for special effects. next will "i love it" be the star of the summer? see how you can vote. [ lighter flicking ]

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usher's son has a close call in a pool and an american tourist made to look like a fool. that's tonight's feed frenzy. a pool accident, singer usher's son is in the icu today. he was playing at home when he apparently dived into the pool to pick up a toy and then got his arm stuck in the drain at the bottom of the pool. usher was not at home at the time and the boy's aunt and then maid were unable to free him. two men in the house eventually saved the boy and administered cpr. doctors say he will recover from

the accident. hands off. in a very different type of accident, an american man visiting florence, italy forgot the cardinal rule of museum going. look. don't touch. holding his own handled up to a 600-year-old statue near the duomo, the tourist broke the pinky right off the priceless piece of art. art lovers around the world may now want to raise a different finger to him. summer songs. as we enjoy the last few weeks of sun and sand, the battle for official summer anthem is on. ♪ i don't care ♪ >> the show "girls" gave the stamp of approval. robin thick won himself controversy for blurred lines. and there is the can't hold up. and miley cyrus's we can't stop.

so you tell us. what's your soundtrack to summer 2013? go to our website to vote on your favorite. that vote is on our website. abc news.com/"nightline." thank you for watching abc news. world news now is coming up soon with overnight breaking news. tomorrow on "nightline," the sole survivor break his silence to talk about the fateful day he lost 19 of his firefighter brothers. i'll see you on "good morning america" tomorrow. good night.