with anderson cooper error is next, right here on cnn. thank you so much for joining me this evening. i'm alice in camerota had a wonderful sunday night and come welcome to the whole story. i'm anderson cooper. sharks had been around for at least 400 million years even before dinosaurs walked the earth these apex predators have reputation for attacking all sorts of marine life, which sometimes includes the occasional human. but are shorts danger to people or people at danger to sharks? according to scientists, more than one-third of shark species are at risk of extinction, mostly due to overfishing some fishermen in the u.s. argue that sharks are coming out in greater numbers in every stealing their catch and making it harder for them to earn a living. seen as bore sanchez is an experienced diver and over the next hour he takes us underwater, with sharks to show us both a beauty in danger of these creatures. we want to warn you some of the images you'll see in this hour. maybe disturbing below. >> the surface at tiger beach you're supposed to steady your breath limit your movement and keep your head on a swivel there are shadows lurking ancient predators with remorseless eyes staggered rows of razor-sharp teeth circling closer jagged silhouettes that hold a lethal reputation a beast that inspires dread and all they are such fascinating. >> iconic creatures it's like a cross between a dinosaur, a tiger, and a puppy dog they eat everything. >> they're eating machines. the other dangerous you go into water. you got a good chance of getting bit how about the word vulnerable how many people would also say the word shark? >> with vulnerable sharks are now at the center of a deepening conflict there's just a lot more sharks out there. >> so there's a lot more interactions my question is, is this the new normal between those competing with apex predators, angular's struggling to make a living off the ocean. >> you go out there and about half of your kitsch is eaten by sharks. >> and those who know these creatures by name and personality. >> i can say grandma was comfortable with me. i say grandma allow me to have her in my lap and pattern literally advocates who say a negative reputation is unwarranted are worried that current global trends signal a bleak future. they're not these mindless eating machines. there's so much to learn about them, and there's so misunderstood the movie jaws famously portrayed shocks and the huge threat. you're going to need a bigger boat it was so successful that are caused the whole genre of hi, it's can be produced. that's perpetuated, that message people think of shark and they think of violence stuff gore, blood teeth, and nothing could be further from the truth they aren't mindless killers, but in fact, these amazing curious, and just graceful animals three victims injured in separate shark attacks, while shark attacks do happen, experts say they're rare checks can be a risk to human beings. >> but we have less than ten fatalities a year worldwide we're here inherent coal for nova scotia we are tracking some of the white checks in the range and boris worm is a marine biologist in nova scotia studying shark populations what got you interested in sharks? well, about 20 years ago we realized that shocks were on their way out, that there are populations were declining in many regions and that really shook me our research has shown that about 100 million sharks are killed every year around the world more than one-third of shark species are threatened by extinction right now, like the great hammerheads sasha sharks, oceanic white tip we need sharks because they have been a functional part of ocean ecosystems for at least 400 million years. >> that's twice as long as dinosaurs they actually survive five major mass extinction event in earth's history. and they have their sixth extension now. and it's driven by us sharks are older than trees sharks as a group or older than the rings around saturn marine ecologist neil hammer slag operates short expeditions in the north atlantic we know that predators in general health, maintain balance and regulate ecosystems when they are removed, there can be this trickling effect throughout the ecosystem. if i have a fancy watch, right? and i opened it up and i pull out a random spring. i'm not exactly sure what's going to happen, but probably the watch is not going to function as well. lot of people like think about sharks role in the ecosystem. they're eating all these fish and helping control populations that way. well, they certainly have to eat. but one of the big ways that sharks have helped balanced ecosystem it's them is by scaring fish. and that's important because it prevents any one species from like taking over and out-competing the other ones which promotes diversity shaq's often be alive young, like us, they materially like us. they have few offspring throughout their life humans couldn't be fish sustainably over time. she is candy either what do humans use sharks for? shark meat for a long time was not prized at all. shocks were often caught accidentally then in the 1990s, with increasing afterwards in asia, particularly in china and neighboring countries shark fins became a highly priced delicacy it was seen as a cultural sign of wealth having shark fin soup, certain fins are more valuable. they could go from 50 to $500 a pound and what would happen is the sharks would be brought towards the boat it's something called finning the fins would be cut off and the rest of the shock would be thrown away at sea to die essentially, the sharks suffocate to death, mutilated sharks cause an outcry and that contributed very much to the heightened extinction risk. we now see for sharks since then that practice of cutting off the shark fins and selling them for profit has been banned in many countries. now phish's are incentivized to land the whole shock what is happened is that it seems to have created a bit of a demand for shark meat. and also a very rapidly increasing trade in shark liver oil. >> a very valuable oil called squalene, which is used, for example, in supplements or in cosmetics despite an increase global demand for shark meat, the fda warns that it could contain high levels of mercury. shark meat is not good for your health. so my own studies have found that sharks tissues have very high levels of toxins like mercury, arsenic, and even in your logical toxins are linked to development of alzheimer's disease in humans, you did research about shark finning regulations and whether that helped to reduce mortality. >> what did you find? >> we were, really interested in finding out whether the rise of shark finning regulations around the world has helped to reduce mortality of shocks and the short answer is no. it did not because it simply incentivized fischer's to land the whole shock, use, the whole shock, creating additional markets for their products. in some sense raising the value of the shark worms research also looks at the countries were the most sharks are killed while indonesia regulates shark fishing it tops the list with a legal shark exports. you see the big six 66 countries make up 50% of global shark mortality. >> as you see, the united states at number eight, with an estimated 2.8 million sharks killed according to our data, it's a major shock fishing nations, but they're also doing things for sustainability but i think most people would be surprised to learn that there's so many shots being fished in the states how serious is the overfishing of sharks as a problem around the world? the loss of sharks from directed fishing from sharks and also sharks being caught unintentionally is a major, a major problem. this is like a global phenomenon despite warnings that sharks are in danger globally, some anglers say the short population in the united states it's out of control at shark disdain it right there at a recreational fishermen says the humanizing of shock parks has gone too far. i could show you pages and pages of instagram accounts on personal sharks that people are feeding off the coast of florida they have names. this is snooty, a female lemon shark. >> i do not see kids going to farms and naming chickens and naming cows next we traveled to the bahamas to meet those naming sharks and we get a close to some of the creatures they're trying to say do you think the shark knows you're trying to help it? yeah, i do. advise why we should keep coming back when it hurts. it's trying to remove a whole hertz but she'll do a tight circle and come back violent earth with liev schreiber tonight did nine on cnn you know what's brilliant thing about it. boring is the unsung catalyst for bolt. >> what straps mold to a rocket and hurdles and into space or boring makes vacations happen, early retirements possible, and startups start off because it's smart, dependable, and steady. >> all words you want from your bank for nearly 100 let me 60 years, pnc bank has been brilliantly boring. so you can be happy and fulfilled which is pretty and boring if you think about it every birthday marty. >> oh no, yeah. do let me get this thanks. you're too kind i've heard that unlimited 2% cashback. the wells fargo active cash credit card get the moon so lining back down every day, mission and innovate to move the world forward on the road and far beyond michelin motion for life once upon a time there was an infinity meticulously crafted to stir your imagination and daring to dream luxurious. three roe drink for everything, for every passenger could be just right introducing the all new three roe infiniti qx at greetings happen. purity, yeah that's not good. happened huge things happen happened with three jump early brende deals at amazon.gov, dr. sanjay gupta reports the last alzheimer patient next sunday at eight once cnn for those who cherish shark interactions few places on earth rival the bahamas sharks are leaving breathing, thinking, feeling sentient beings, which unnecessary our world and that sharp junction, a dive site just offshore from grand bahama is ireland. christina's nato feels at home what is it like when you are under the water with sharks? >> to me is like being home. it's as as peaceful as cillian on my couch pet and my dogs. i'm happy i'm relaxed. i enjoy their presence shift for me is an animal that is easy to understand. it's not conniving. and who's now backstabbing? i deal easier with sharks. sometimes and i deal with people you've never felt fear in the water with sharks and never felt fear now, i grew up with the notion as a very beautiful sentence on my dad always told me there are no monsters in the sea, only the ones your makeup in your head you were instrumental in changing the way that sharks are treated here in the bahamas. >> i started a petition in 2009. the gathered at the time, 25,000 neutres online petition that helped establish a marine sanctuary for sharps across the bahamas, 700 islands you cannot fish, you can i'll kill, you can land a dead shark. over decades of divs is an auto has seen generations of caribbean reef sharks come and go learning their patterns and fostering relationships. >> we actually recognize each and every one of them. i have hand signals with their names and i can point them out to you and i have personalities as well. >> personalities will greet once we sued up all right. >> so change shirt that we are using is this one here. then slide it over. kept kinda like a knight in shining armor. the nerd design, a two prevent abrasions and cuts the exact full board ready to go does we go down where reached the bottom of the line is 30 feet and then we'll know right in the middle of the set and as we settle into position, z, nato spots familiar faces but we have hook we have a house we have balkan, we have crook we have floppy three child and pet the shark head. >> same as if you would be shaking somebody's hand relax, right? gentle breathing. don't trying to do too much way for the shark to come in. you're going to reach out and pat i had a shark could call grandma known for 14 years. and now she she's gone from my accepted me. i can say grandma most comfortable with me. i say grandma, allow me to have her in my lap and pattern literally it's every time the same feeling. it's a magical moment for in 8.5, nine for wild-animal to say in this moment, i trust here and i will sit here with you. so i always worried why do if they go into the florida waters when they're not protected? what if somebody comes here a night and nobody but he's watching and does something to them. so it's a mix of law and worry when i'm with them aims to heal those wounded by fishing hooks it wouldn't when a shark shows out with a whole i tried to see where the hook is lodged. >> if the shark is willing or maybe stop the shark tried to grab the hook. >> do you think the short knows you're trying? to help it? >> yeah. i do advise why we should keep coming back when it hurts, because strength to remove a hook, hertz but she'll do a tight circle and come back in in 30 years of removing more than 350 hooks is an auto says she's never been bitten by a shark they can be sometimes demanding bread the satisfaction of being able to relieve i shark, all that presence is an order may and that was it. that was unreal. who was really good? very nice tomorrow. >> we're headed to tie your be able to do some free diving do you have any advice? >> where two eyes on the back of your head that the cayman jason mr. sanchez, it's grown up in a look of a board. >> my friend more than two hours off the coast of grand bahama. tiger beach is world renowned for its strike namesake unlike reef sharks, we will not be padding tiger sharks among the largest of the species they can weigh nearly a ton and they grow up to 18 feet in length they're perfect models for conservation as jason washington and award winning photographer, a claim for his work with free divers why freed? i've tiger beach gives us an opportunity to get a little bit closer. under the animals, but the shark is going to be moving all around us while we're down there. so it'll give us an opportunity to swim alongside with these creatures. what does your ability to photograph them and shine a different light on them mean for conservation, when you want to turn the world on to the plight of these animals, you want to get the water with the big ones and show the viewing audience that they're not mindless killers they play a critical role in our world's oceans and they deserve our protection. >> and i do that specifically through photography we've close thing i do. we have prepping, not beit we have one bade was we need high off to a funded a both mosley keeping some socks and themselves up to the funding to vote we happen to be diving with some of the best in the industry today. he'll be up to lewis base. we do not touch the show dollar. let this are that seila right you see me go 456. got numbers besides knife beautiful, majestic creatures by mess, not get the tags, have that opportunity to get too close to us we have a, second, be blocks don't know. that's the, the, the mean bag walks. we'll friedman from so you saw familiar face down all right yeah. he's out. let's be frequent, it beat fireball by was six years he's quite famous actually her name is but ways we go along even mean place little. he sees indented these lastly, want to dmo sneaky most it is, is come route. they come nice and loose data made box three sleep does would see what to do with bird face plays by her own rules, 30 much speed. >> as free divers, what we wanna do is get our heart good morning, get our co2 levels. well are oxygen levels are high so we do that through a brita process correct. ready for this? let's do it what we're looking for immediately as we enter the water are these limits? ends in these reef sharks that are circling behind the boat they're going to make our way back down toward the end of this tagline. and that's where we'll be free diving from now these sharks on the bottom are going to be coming into the bait station they're going to make a big circle and they're going to come into the base station to get their hand out of food, their treat and then when we feel like we're in a safe position we're going to dive down in swing with these animals. so i'm going to be taking pictures of you with the tiger sharks and the background make sure you're looking all around above. hello? >> all the sides. because these sharks can come from different angles the amount of energy that is spent getting down, they're getting close to the shark, keeping up with it, and also keeping your head on a swivel because there were several moments where you're focused on one and a couple of them are behind. >> you or in your peripheral. so it requires a lot of energy to not only be close to the shark and moving with it, but also to be alert it's almost the same every time for me. it's that slipping beneath the water the world suddenly becomes more silent all the things in my mind are pushed to the periphery and i'm focused 1,000% on the sharks. it is the most present that i will ever be watching the feeder is almost like watching a bullfighter. the way that they navigate the space and they navigate the animals intent and interests because they are very interested in what's happening happening in that box and sort of keeping it at bay and managing an dancing with it in that moment from an up-close view, there is nothing like that. the world you might have so we've got a chance to swim with them, right now. i'm going to run some scuba gear. in face-to-face it's clear getting that close to a tiger shark and making eye contact with this miracle of mother nature matsu dinosaur, knowing that it is fully capable of ending your existence and then watching as it examines you, sizes you up and then shares the ocean with you and moves to the side that to me is profound it's just on inspiring. >> they come fairly close to you could just reach out and touch them they don't really even care that you're there i think but face has a bad reputation because she was nothing but pleasant to me personally i'm literally capturing everything that's happening around me. i'm framing the image and then try to line everything up in a composition that's pleasing to my brain. it's, it's a difficult process and it's one of those things that just keeps you coming back for more and the more you do it, the more addictive it becomes because that's suddenly where you understand that this world is a lot bigger than when we return controversy over shark fishing tournaments, it was just gruesome. >> and allegations of animal cruelty when frustration boiled over, just violent, angry said mob mentality. >> and later real, real, real, real, real, real, real. we meet a world-famous shark country. so what's the procedure now is the protocol at a great hand? 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>> when you kill a certain number of sharks like that, it pushes all the other sharks out and a lot of fishermen kept killing sharks after the tournament. so there's a whole saying, do your part killer shark i made a video that went viral on the tournament quickly after i posted that video, i had a couple of people show up at my house wanting to get violent it was a pretty scary time because i was getting death threats there's a lot of fishermen out there right now that are very frustrated with sharks. >> so they have a neck we're gonna have connotation because they keep interacting in a bad way with the fisher the tournament's organizer, robert flying navarro, says he also became a target i was averaging between two to three death threats on night. >> what will people saying i'm going to shoot you just like people shoot sharks you've heard the reports. i'm sure if people misbehaving i heard reports of people misbehaving. i never saw anybody missing misbehaving folks doing inhumane things to the sharps. that wasn't the intended purpose. we had a university that was doing samples on all the sharks. i know we harvested nine sharks and we released somewhere like 287 sharks. all i know is we had a 97% release rate, which all that stuff went back to noah but the number of sharks released was thrown into question when hidden camera video that was shot for a documentary circulated on social media, it captures audio was a tournament official instructing fishermen to take the fins and take the meat before dumping dead bodies in the ocean. navarro, who was at the meeting later admits more sharks could have been killed than those they harvested inside video also captures a fisherman bragging about dragging a sharp behind a boat for hours. a state crime and florida drug this fish for two hours is it possible that there were folks that did things that you wouldn't sanction 100%. >> i cannot i don't know what everybody is doing out there. >> you're a post, a short colts. i owe 100%. i don't want sharks called we do not sponsor any tournaments. >> we'd only require that people holding the tournament register with us and that is so we can collect the data kara brewster guise helps write the rules for noaa fisheries. a division of the national oceanic and atmospheric administration do you think that having these tournaments gives cover to folks who might do things that are in appropriate. >> they're going to be some people who try to skirt the rules. if you question whether or not they are fishing correctly, reach out to noaa law enforcement? >> backlash from. this and other tournaments over the years has forced some to shut down. don't navarro is now planning another that he says will also be within the rules a few miles south one florida fishermen who no longer participates in tournaments has become famous for his prolific shark hunting. how long have you been martyred for short? oh, since early 70s when jaws came out, the movie, i was sharp vision then, but it then it's made my business skyrocket because dba wanted to catch a sharp customers, hire him to take them shark fishing. how many shirts do you think you've caught over the years? by 100,000 shorts? 50 years don't forget the longtime i mean, if you're out here every day like we are, we're out here 450 times a year. we see what's going on. it's a lot of fish that are on a protected list that should be off their protect the list exam we're going to measure her up dagger and let her go. there's plenty of sandbar sharks are out. i mean, you could catch and just about every day of the week a. why are they on their protected list? i don't know. they shouldn't be they should be taken off. i get a bit too quick okay. what would that door ran hou go he tagged probably a couple of hundred sharks a year for noaa national marine fisheries. they love us all. hey, i just keep died. give a going to give it go and give it a little bit of time. i got about data ban male wow, rows. they don't bleeding or bleeding all over the place well. there's no part of you that feels bad about that short and having a diminished population and you taking one out of order, in my opinion, there's no diminishing of a population of hammerheads. they're everywhere. we catch it all the time. if there's so endangered, why did we catch him every day? just think about that honestly, what would you say to folks who think that you're doing arm to short populations, one guy doing shark populations arm, i don't know how how does that work. i mean, i'm getting way too much credit agnes neuter how many times have you gone out fishing with mark 30. >> 30 plus maybe maybe 40 times. >> what is it about shorts that attracts you to this kind of fishing? i find it similar probably to like anybody that wants to big game as long as it's positive legal in the right waters. >> i think big game hunting, a lot of people all over america enjoy it, should we stop for a moment? >> just look over there soon after docking law enforcement approaches the boat all right. >> there are so mean to mark everyone and i put that on film erode. so mean to mark marks a good person salmon always calls the police on us to police officer know that we don't do anything illegal with totally hundred percent by the book, right here. >> let me you guys despite warnings from the fda that shark meat could have high levels of mercury, meat from this scalloped hammerhead will soon be delivered to a local homeless shelter, which more it says he does with every catch good job, bores coming up. we had to west palm beach to explore angular's frustration and cy, they say the u.s. government is leaving them high and dry as one you just got shark surprise see, this hosted shark week sure. >> he's back. who is the alpha matte a still about to get the chunk might show shortly, was good. i can see that starts next sunday evening and discovery extreme on max oh, kurnia zelda. >> it's gotten me. i saw them. that's what i got agnes carnegie out to me, carnot. well, with more flavored gardening, carnage, tracing it like this juicy i did it my favorite news for just $40 a month my favorite news for just $40 a month. $40 a month like favorite news for just $40 a month $40 get your favorite news are $40 a month sling lets you do that. >> some are savings are on the way, wait, wayfair's fourth of july clearance is here and it's the talk of the neighborhood because now the july 7, you can save up to 70% of everything yeah. save on binds for indoor and outdoor and gets the price blache deals, you don't want to miss and get it all with fast shipping straight to your door, save up to 70% off with wayfair's for the july clarence. now through july 7 and r& up your summer with savings play every style, every home mark ross thank you. >> an alternative to pills, walter and is a clinically proven arthritis pain relief gel which penetrates deep to target the source of pain with non-steroidal anti-inflammatory medicine directly at the source volterra and the joy of movement jesse loves playing detective, but the real mystery plus, or irritation good skin. so we switched to tied free and gentle. it cleans better and doesn't leave behind your attaining residues. and it's gentle on her skin type free and gentle liquid is epa safer choice certified? >> it's got to be tied at fisher investments. we may look like other money managers, but were different. >> you can't be that different. >> we are we have a team, a specialists, not only in investing, but all so in financial and estate planning and more your clients rely on you for all that? yes. and as a fiduciary, we always put their interests first, but you still so commission-based products, right? no, we have a simple management fee structured, so we do better when our clients do better we're more different than i thought at fisher investments were clearly different cities, industry-leading global payments solutions help their clients move money around the world seamlessly in over 180 countries and help a partner like world food programme as they provide more than food to people in need together, city in the world food program empower famili doctors preferred better science, better results dr. sanjay gupta reports the last alzheimer's patient next sunday at eight on cnn now you are doing workout today. >> no idea when we got, uh, rainbow runner along doing this professionally, i've been doing it 33 years good luck, buddy. it's become a little bit of an issue. number one, with a lot of boats. number two, to the shark problem robert flying navarro says that competing against predators on the open water is natural shark. >> shark, shark. but the rate at which sharks are feasting on it he's catch is crippling both the commercial and recreational fishing industry. >> it's every fisher fighting navarro says sharps are eating what he catches before he can relay into the boat at an alarming rate he says the phenomenon known as depredation is happening more often than he's ever seen, lead back. and then why now there you go he's having dinner tonight? people aren't and keep one and he's still there or did he get bid on this one you just got shocked. you think so you have a liter. >> you see the that's the shark be just h or dorado. how do you know for sure there was a shark though feel that oh that's sharpie grabbed fish and poultry are could you imagine if you spent $3,000 to go fishing to catch that fish for dinner? i, just got eaten, aiming to curb declining numbers. the national oceanic and atmospheric administration began implementing protections on sharks in the early 1990s oh sure. shot right there. but you're right there. okay. yeah. here you go. >> tighter regulations mean more sharks. and according to navarro, more sharks mean more encounters oh, there's a shark that just stated. he just stayed at cm right there. he just eight your make your fish it's three today that we've caught or that we've got up at the sharks, even write it. the next is about it's a lot of work. it's a lot of work only to what loser right at the end. it's time to end it come home empty handed the question is, are they trying to rebuild the stocks back to 100% or they trying to rebuild them back to a manageable level. and that's a question that i asked the agency this week, going forward, navarro is a member of noah's advisory panel for highly migratory species like sharks right now, depredation is a very big problem. other frustrated fishermen joined him in dc. >> this may to voice their concerns i've got videos on my phone that were sent to me from southeast florida of sharks tear in the selfish up that they're trying to catch every is shark just the right care? it would gum frankly, a lose-lose for pretty much anybody fishing anywhere from maine through texas. why is that? because the abundance of them. >> so we're going to check this every ten lines. >> but some scientists disagree. catherine mcdonald, who runs the short research and conservation program at the university of miami. >> so we're going to take a look argues depredation may be due to overfishing for the most part, fishery is independent monitoring data does not show a huge population increase. we may be depleting praise sources so that that increased competition has more to do with fewer fish to go around than it has to do with more sharks. there's a lot of scientists actually worked hang on this topic right now. the question isn't, are those conflicts going to occur? because we know that they are. it's how do we want to manage them and what do we want the future to look like? >> so what was it that got you into marine life no official see the problem is complex without an easy remedy, we have been really successful in noaa fisheries at rebuilding some of these stocks. but there are a lot more recreational anglers now that means there's a lot more fish being discarded or the fishermen are practicing catch and release. all of that is going to train sharks is there any science backed data that proves that depredation is a problem? one of the things now a fisheries is trying to do right now is fund a lot of research looking into two depredation. but the solution is not going to be called all sharks. sharks are bad and you get rid of them. >> looking to know, look, he's getting chased. the chart. >> our solution is gonna be something to minimize the interactions between sharks and the fishermen. and so first, we have to collect the data collecting that data involves serving populations or stock assessments, which fisherman like fly thinks needs to happen as soon as possible. >> i would agree with them so then what's the challenge in getting it done? he because he feels like the federal government isn't listening to fisherman like him. >> we try very hard. there is a whole process. we work with in noa. we worked with other groups to determine which species, not just sharks should be assessed when it takes time to do the assessments when we. return scientists inspiring the next generation of researchers. >> it's to give them that firsthand experience, their own story that they will carry with them as the future for sharks appears murky. if we keep killing 100 million sharks a year where would that leave us kurnia zelda. >> it's got an answer. that's what i said. god got got a nice, juicy gardeners i did and you swore you don't roll on rows bookstores. >> i read that one. i read that one. i read that i didn't read that one. didn't read that. can you get this? 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sharks have a byte and a slap the end, and we don't want to get bit and we don't wanna get slapped we'll get you in position. we'll call you when we're ready. all right. we've got our measuring to your first pull it away and read it well there you yeah, awesome nice thing about when you go to the doctor, right? and you get your physical or checkups gets really the same kind of thing that they're doing. >> and this is a clipping, a small clipping of the fin yes. >> so it's a small piece of a fan, think of like clipping your fingernails or cutting your hair. it's not hurting the animal out feeling at if you're doing that right, you should leave feeling it and it's giving us dna. you can do a sharp family tree, essentially. >> so what's happening now? so now we have a student who is placing a tag and what is a tag keeping track? of their looking at how many sharks are caching, which species, and then that tag number is linked to all the other data. how does this help protect sharks? >> so you have to have baseline data. you have to have an understanding when people make statements like populations are going up or down. or you hear plus elders too many sharks, you don't know that unless you have data so you just talked a short. what was that like like it's about 20. >> we're really cool. yeah. >> you'd like charts what was going through your mind as you were looking at it, as i can't believe i just tagged this shy collecting one key data point from the seven shorts they tag is especially critical given that these waters are actually a nursery. and this is a sonogram. it's a completely different really exciting so if a little spark can make it here they can make it another places or they need to co-exist with people and that gives us a lot of hope for the future of shark conservation hope that globally seems to be in short supply. and the odds are stacked against the shocks for every human that gets killed at least 10 million tracks get killed we'll never overfished. the scary part of their being fished sometimes before they can even reproduce if we keep killing 100 million sharks a year where would that leave us? i'm not sure where would leave us. where would leave shocks is with a lot of species going extinct. one and three shocked species minimum, right now is threatened to go extinct in the near future. because of overfishing. those species will never come back. they will never contribute to a healthy marine ecosystem. again, i'm really worried that it would put ecosystems out of whack and away. we don't completely understand you just dip. it out of my head. shark deportation is an issue and i think is an issue that needs to be addressed. but i don't think calling sharks is the way to dressed i think there needs to be more science behind what are the factors that might increase and deep predation rates? because if we can understand what goes into that, then maybe we can modified the way we fish in a way that could reduce the that. >> we see sharks slowly recovering in some places that protect them. >> u.s. as one example, three and good fisheries management, some sharks are recovering at the same time other species might not recover because we're still fishing them we definitely have some shark species that are in need of conservation. >> we also have some species that are really healthy and that can withstand a lot more fishing pressure than we allow while i'm the good news is that over fishing is the main threat to sharks by far. and overfishing can be addressed by changing human behavior we can regulate the numbers of shocks that are allowed to be landed. we can regulate the fishing gears that are to be used and we can have wider regulations on say, which species are allowed to be traded over international boundaries how important is it to change the perception that people have of sharks? well, i think it starts with seeing shocks for what they are and not what we're made to believe they are. and he seeing them as a vital and critical part of ocean ecosystem, something we cannot afford to lose we can reduce over fishing. we've done in the past. we've done it for other species safe males are saving totals. we can save sharks a challenge that will define the health of our oceans for generations be, have taken hundreds of kids out in the field to tag sharks. >> it's to give them that first pretend experience, their own story that they will carry with them. it's not what they read in a book itself, what they saw on tv, it's not what somebody told them like be afraid of sharks. it's they have their own connection and their own story and that stays with that. they are wild animals, but they're not monsters and they're in big trouble and. if we don't have these conversations and we don't support research and conservation. they're disappearing and they're going to keep disappearing. so the time is now to take action to save these animals florida learn more about these fascinating creatures. students are shark week on discovery, which is also owned by cnn's parent company, wbd.