- il y a 5 mois
Documentary on Animals : Tiger Shark, Bull Shark, and the Great White (Full Episode) Dangerous Encounters Nat Geo Animals
National Geographic Site officiel : https://www.nationalgeographic.com/
National Geographic Site officiel : https://www.nationalgeographic.com/
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00:00Sous-titrage Société Radio-Canada
00:31There's got to be a lot of bacteria in there.
00:34Swim beside them and take to the skies with high-tech equipment.
00:40Oh, man, it's perfect. Stay there.
00:42What they capture could change how you think about the most notorious hunters in the ocean.
00:48That shark just exploded out. Completely cleared the water.
00:51Oh, look at that!
01:03Look at two of them.
01:05Look at them.
01:05I thought the sharks were going to just slam into the boat.
01:09The east coast of Florida, a prime feeding ground for one deadly predator, the bull shark.
01:16I count 13 big bull sharks all over six or seven feet.
01:21Look at them all. I mean, that is amazing.
01:22Reptile expert Dr. Brady Barr will explore what goes into the bull's attack.
01:29I mean, they just all came in together like a phalanx.
01:31And they are getting fired up.
01:33All this action.
01:34Look at the shark right below the boat.
01:35Pull it in and see one just hit it.
01:41Oh, yeah.
01:43Look at that.
01:44One bite.
01:45One bite.
01:46It's hard to even get a knife in this fish.
01:48You can see the individual teeth marks.
01:50That could just as quickly be your leg.
01:53Shark attacks on humans are rare, but most are carried out by just three species.
02:00The great white, the bull, and the tiger.
02:05That is just a massive animal.
02:08The great white has a reputation as the ultimate ocean predator.
02:12But is it?
02:14Brady will put all three species through a battery of tests.
02:19Got it.
02:19Got it.
02:19We got to fight.
02:20We got to fight.
02:21And that will be highly dangerous.
02:23Come on.
02:24Open your mouth.
02:25Brady will look at how hard these sharks bite.
02:28That's a huge bite.
02:29That's comparable to a great white shark.
02:31The deadly bacteria they sink into their victims.
02:35Good night.
02:35And the different ways they hunt.
02:40Woo-hoo!
02:42The great white has a powerful weapon that many believe make it the ultimate predator.
02:50So Brady will use cutting-edge technology to capture breaches like never before.
02:55Oh, that was awesome!
02:56The results could challenge everything you thought you knew about these attacks.
03:03I don't think that they're exploding out of the water and always getting that seal in their teeth.
03:08I don't know.
03:09I don't know.
03:09I don't know.
03:10Everyone knows the great white has a deadly arsenal.
03:12I don't know.
03:14I don't know.
03:16I don't know.
03:17I don't know.
03:17I don't know.
03:17It's a giant shark.
03:18First on deck, the species commonly considered the most aggressive.
03:28The bull shark has got a really wide head,
03:32meaning it could have a tremendously powerful bite.
03:36Also, the bull shark is unique in that it can spend a lot of time in fresh water.
03:40Now the question is, is it more dangerous?
03:43I aim to find out.
03:48The first test, bite force.
03:51Brady will have to get within inches of the bull's jaws
03:54to see if they're as powerful as the great whites.
03:58That thing is strong, isn't it?
04:01They're called bull sharks because they're a lot like a bull.
04:04They're big, muscular, wide-bodied, barrel-chested.
04:09Very, very powerful sharks, and that's why we're here.
04:12Captain Mike Newman is an expert in finding bull sharks.
04:15They'll start a frenzy now and watch this.
04:19Oh, careful.
04:20It's just an aggressive thing because they're agitated.
04:25Bulls are relatively small by shark standards.
04:30The bull sharks don't get huge.
04:32They top out at about 11 feet.
04:35But very strong-bodied, very powerful sharks.
04:37Bulls can use sudden bursts of speed
04:41to attack almost anything that crosses their path.
04:44Other sharks, dolphins, sometimes even people.
04:49Peter Benchley based his novel Jaws
04:52on attacks that were probably the work of bull sharks,
04:55not great whites.
04:56But how much force is behind the bull shark's bite?
05:00Oh, look at the size of that!
05:03That is a monster bull shark!
05:06That's got to be close to 500 pounds.
05:09I mean, that's a monster.
05:10That's about the maximum size for a bull shark.
05:13So if you're in the water with one of these bull sharks
05:15and you see it's back arched
05:16and those pectoral fins go down, man,
05:18you need to really be cautious.
05:20If you would get in the water with this one right now,
05:21it would probably bite you.
05:23That's not going to happen.
05:24We don't have to worry about that.
05:26We're staying on the boat.
05:27So the idea is you're just going to pull the shark's head
05:31up out of the water
05:31and I'll stick the bite force meter down in there.
05:33Exactly.
05:35Probably easier said than done
05:36when you're talking about a 2, 3, 4,
05:38maybe 500-pound angry bull shark.
05:41Over the years,
05:43Brady has measured the bite force of many animals.
05:4695 pounds of force.
05:48Ranging from hippos to humans.
05:52He's even tested the great white shark.
05:55I mean, 6'6", 9.
05:57That is a heck of a bite.
06:00669 pounds.
06:02That's the biggest bite force reading
06:04Brady's ever recorded from a shark.
06:07Can the bull shark beat it?
06:10The bull's got a wider head than most other sharks,
06:13including the great white.
06:16In shark anatomy,
06:18width usually equals muscle.
06:20More muscle could mean more jaw strength.
06:23Come on, open your mouth.
06:31We got a bite, 6'1", 6'.
06:33Wow.
06:346'1", 6'.
06:34That's a huge bite.
06:36That's comparable to a great white shark.
06:38Look how wide this head is.
06:39The wider the head,
06:40the stronger the bite.
06:41Now, this animal is only 7 feet long,
06:44and we just got a bite,
06:45which is over 600 pounds.
06:47I mean, that's one of the strongest bites
06:49I've ever recorded from a shark.
06:50We used to say that's even a maximum bite.
06:52That might have been a weak bite for the bull shark.
06:54Unbelievable stuff.
06:566'1", 616 pounds.
06:59That's like being pinned beneath a Harley Davidson.
07:03And when the bull's teeth sink into prey,
07:06they can do serious damage.
07:09Bull sharks have very unique teeth.
07:11Broad, triangular teeth on the upper surface,
07:14but on the lower.
07:15White at the base and narrow at the tip.
07:18Different types of teeth on the upper and lower.
07:20Man, that's exciting.
07:21Like the great white,
07:25the bull's triangular lower teeth pin its prey,
07:28while its upper jaw moves out and down,
07:32delivering the full force of its bite.
07:36The bull has a lot of power in its wide jaws,
07:40but a single bite won't tell the whole story.
07:44Time to check another.
07:50That's a big shark.
07:51Look at those teeth.
07:54Oh!
07:55989.
07:58989 pounds.
07:59That's literally half a ton of bite force
08:02from a 300-pound bull shark.
08:04Ripped off all the waterproof housing
08:06on the bite force meter.
08:09It's an extraordinary result.
08:11The strongest bite ever recorded from a shark.
08:15Any shark.
08:16The bull shark may be half the size of the average great white,
08:22but its wide head gives it a far stronger bite.
08:28Still, bite force alone won't determine which shark is dead last.
08:32Sharks almost never attack humans.
08:37When they do, most people actually survive.
08:42But even if they make it out of the water,
08:46they may face a silent battle against infection.
08:51Victims can lose a limb, even die.
08:54We're going to get a bacterial sample from this bull shark.
09:00The idea is it's going to bite onto this rubber slug,
09:02and any bacteria on its teeth will remain in the rubber.
09:06This is likely the first time anyone sampled the bacteria
09:09from a live bull's mouth.
09:11That sample's going straight to the lab.
09:37It'll take time to get the results.
09:39Meanwhile, there's one more factor
09:42that could make the bull a deadlier predator
09:45than the great white or the tiger.
09:48Their attack strategies.
09:50Big dark one. I think he's going to get it.
09:51Ooh. Let's see if we can get him to bite.
09:55He's going to not really eat it. See that?
09:57Yeah.
09:59Bulls are known for doing the bump and bite.
10:04Ramming into their prey and then biting it.
10:06It's considered one of the most aggressive sharks,
10:11and it has a bite force that's far higher than the great whites.
10:17Oh!
10:189.89!
10:20Woo!
10:21Then again, the bull doesn't strike so hard,
10:24it actually leaves the water.
10:27It's hard to believe any shark can match the great white's assault.
10:31New technology could capture the action
10:40and show this killer ambush from an amazing new perspective.
10:46But first, there's another shark
10:48that combines its own powerful assault
10:50and the great white's size into a deadly combination.
10:54It's time to find the next candidate,
11:14a shark that could be the deadliest predator in the ocean.
11:18Brady's headed to Bimini in the Bahamas,
11:21where tiger sharks are often found.
11:23The tiger is known as the trash can of the ocean.
11:28It eats anything, living or dead.
11:32It can even crack the extremely tough shell of a sea turtle.
11:37Does that mean it's got a bigger bite than the other sharks?
11:43The answer could come in a surprisingly small package.
11:50We're in less than five, six feet of water.
11:52Yeah, it's pretty incredible.
11:54We're thinking there's going to be tiger sharks.
11:56Everything hanging around in this little bit of water.
11:58Yeah, but we're not after the big ones.
11:59I mean, for our experiments, we want a smaller,
12:02you know, five, six, seven, maybe eight-foot shark.
12:05Shark specialist Ryan Johnson
12:07will help test a new way to calculate bite force.
12:11The plan, use a small shark to predict the bite of a big one.
12:16Did you see that?
12:17Yeah, I mean, I saw a white belly.
12:18There's something right there.
12:19Yeah, yeah, yeah, it's a tiger shark.
12:21And the better news is it's a manageable size.
12:24It's about this long, perfect for our bite force experiment.
12:29Brady and Ryan need a shark that's small enough
12:32to easily bring back to shore.
12:34They'll electrically stimulate its jaws
12:37to get a really hard bite.
12:40Then they'll use a formula to predict the bite
12:43for a much bigger animal.
12:48Man, that's beautiful.
12:50Ryan will hold the tiger onto the boat.
12:52It may be small, but it has a mouthful of teeth.
12:58I'm nervous.
12:59This thing's got a mouth on it.
13:00Come on, Ryan, get him.
13:08Yeah, yeah.
13:09Come here, Matty.
13:15Oh.
13:16Yep.
13:16Did he get you?
13:18No.
13:19Oh.
13:20Yep.
13:21This is tough stuff.
13:22Here, let me try.
13:23Let me have an attempt.
13:24One, two, three.
13:26I got him.
13:28Yeah.
13:30Put him in there.
13:36Woo!
13:36It's a capture.
13:37That's good.
13:38Good, man.
13:39That's great, man.
13:40He's perfect size.
13:42This shark could provide key insight
13:45into the tiger's bite.
13:47It's time to find out
13:48if the tiger is the ultimate predator.
13:50Dr. Dan Huber has helped develop a technique to calculate the bites of tiger sharks of all sizes.
14:03Are we ready?
14:04Yeah.
14:05We can send a model electrical stimulus to the jaw muscles and get them to contract as hard as they can,
14:10and then we know definitively the maximum bite force of that animal.
14:14Now, the shark we're getting ready to do is a small individual,
14:17but if you do enough individual sharks,
14:19you can predict what a really big shark's maximum bite will be with your data set.
14:26Absolutely.
14:28So how big is the bite force of this tiger shark?
14:34This is going to run water over its gills.
14:36Right.
14:37And also, it's got the anesthesia in there,
14:40so it's going to keep the animal nice and calm.
14:43As the drug takes effect,
14:47Dan carefully preps the shark for the test.
14:52Going in right at the front.
14:56Ready?
14:56All right.
14:57This plate's in good position?
14:58I think we're good.
14:58Okay, hit it.
15:00Oh, yeah, look at that.
15:02That's a good bite.
15:02There we go.
15:03I mean, you see those muscles really contracted.
15:06That's definitely a maximum contract.
15:07I mean, I could feel it really bit down.
15:09Okay, water.
15:10What was our measurement at that time?
15:1518.5.
15:1618.5 pounds.
15:1718.5 pounds.
15:18Now, for a small shark, that's not that unexpected.
15:21But as the sharks get much, much bigger,
15:23what we find is that their bite force increases a lot faster than the size of their body.
15:27So as we zoom this guy up,
15:29its bite force gets higher, faster than it grows.
15:32Based on the results,
15:34Dan projects that a 10-foot tiger shark
15:36would have a bite force of about 350 pounds.
15:40that still seems small.
15:43That's not even half as strong as the bull shark's bite.
15:47And bulls aren't known for breaking through turtle shells.
15:50So how do tiger sharks do it?
15:52First, the team plans to confirm Dan's numbers.
16:00They'll measure the bite of an actual 10-foot tiger shark.
16:05Man, look, we got sharks all over the place.
16:08That's a big lemon shark,
16:09and the tiger shark's over here behind us.
16:10Let's get kitted up before this tiger shark buckers off.
16:12This time, the test will take place on the tiger's own turf, underwater.
16:23With the bite meter prepped,
16:25the team heads into the tiger's lair.
16:39It doesn't take long before they find what they're looking for.
16:43A tiger shark about 10 feet long.
16:45Now Brady and Ryan have to get close enough
16:51to measure its bite.
16:55And there are sharks everywhere.
16:56This cannot be good.
16:58The lemon sharks all around
17:00will make their job difficult.
17:04Whoa!
17:05The thing is nipping at my flippers.
17:10Ryan, Ryan, hey, hey, watch out, watch out.
17:12No, no, no, no, no, no, no.
17:19Oh, he's taking the bait!
17:21Oh, he took the bait off of it!
17:25Without the bait,
17:26there's little chance of getting a tiger bite.
17:31As Ryan heads up to get a freshly baited meter,
17:35Brady's surrounded.
17:42This is crazy dangerous.
17:59Man, I got sharks all over the place.
18:01In the coastal waters off Bimini,
18:05Brady tries again to measure the tiger shark's bite force.
18:08He fights off the lemon sharks.
18:13And Ryan Johnson returns
18:15with a freshly baited bite pole.
18:20Okay, hang on, here he is, right here.
18:22That's the shark.
18:23That's him.
18:23Come, come on.
18:26Man, that thing is huge.
18:29All right, come on, baby.
18:30Come on, come in, bite it, bite it.
18:33Oh, we got it!
18:34We got a bite!
18:35That is a big bite!
18:36Four-one-nine!
18:40That is 419 pounds!
18:42Woo-hoo!
18:44Now let's get out of here before they bite us!
18:48That's more than the bite force experiment predicted,
18:51but it still seems small.
18:54Can the tiger shark really bite through a turtle shell
18:57with just 400 pounds of pressure?
19:02Dr. Dan Huber has a plan to find out.
19:05So what we've got is the fresh shell
19:07from a loggerhead sea turtle
19:09and then a bronze cast
19:10of a portion of a tiger shark's jaw.
19:13And this whole setup is mounted in a hydraulic piston.
19:16And as the piston comes down,
19:18we're going to get an estimate
19:19of the force required to cut through this shell,
19:22which should give us a really good idea
19:23of how a tiger shark is performing in the environment.
19:29Dan turns on the machine,
19:30and the tiger jaw starts digging into the shell.
19:36But even with 1,100 pounds of force,
19:39the shell holds strong.
19:44So it took so much force
19:45to cut through this sea turtle shell
19:46that the machine actually shut down.
19:48That was greater than a half a ton of force.
19:50It seems unlikely the tiger can bite
19:56with more than a half a ton of force.
19:59But somehow, it breaks through turtle shells.
20:04There must be another piece to this puzzle.
20:09It could be the tiger's teeth.
20:12I mean, those teeth are just like teeth on a saw.
20:14I mean, it's just incredible.
20:16See that?
20:17Very uniquely shaped teeth.
20:21They're shaped like serrated can openers,
20:24beautifully adapted for cutting.
20:27They pin their prey with their lower teeth,
20:30while their loosely attached upper jaw
20:32slides back and forth,
20:35cutting like a saw.
20:39The combination of those curved teeth
20:41and the way they move
20:43allows the tiger to cut through turtle shells
20:46despite its relatively weak bite.
20:50The tiger's unique bite
20:52could have another advantage,
20:54driving bacteria deep into its prey.
20:59If shark bites or anything like croc bites,
21:02bacteria is the problem.
21:03I mean, those teeth drive that bacteria
21:05really deep down into the wound.
21:08And you don't know what types of bacteria
21:09you're dealing with.
21:10Very, very hard to treat.
21:12Just like sharks,
21:15the mouths of crocodiles
21:17are crawling with deadly germs.
21:20Look at that!
21:21And Brady studied another reptile
21:23that has a mouthful of bacteria.
21:26The Komodo dragon.
21:29That's the most unbelievable,
21:31horrific thing I think I've ever seen.
21:34Their saliva is so toxic,
21:36it's often lethal to their prey.
21:40Now Brady and Ryan
21:41will collect bacteria
21:43from a living tiger shark.
21:46We gotta be getting close to something.
21:52They're hauling in long lines
21:54to catch another tiger.
21:55And it's a big one.
21:56Over 12 feet.
21:59Dang.
22:01Check it to the shark shark!
22:02Throw it in, shark!
22:03Get in the boat!
22:03Woo!
22:08That is nice!
22:09Look at that!
22:11That's good stuff.
22:12That's a big animal.
22:14All right.
22:18The tiger shark devours
22:20virtually anything.
22:22And that means its mouth
22:24could harbor some deadly bacteria.
22:27How deadly?
22:29A sample should provide the answer
22:31if they can get one.
22:33So the plan is
22:34I'm gonna flip the shark over,
22:36grab a strike,
22:37try it up in its mouth
22:38and when this gets in
22:38then I think we're just
22:39gonna both work together
22:40close it down
22:41and try to get the teeth on this.
22:41Okay.
22:42And the teeth will go in here
22:43and thus the bacteria
22:44will be trapped
22:44in the rubber slug.
22:46Okay.
22:51Okay, you got it?
22:52Give me a bit.
22:53I've got one, two.
22:55Yeah, three.
22:56It's just hard to see them
22:57in the rubber slug
22:57but yeah, they went deep.
22:59Wow!
23:00Okay, so now you gotta
23:00sleeve that up.
23:01We got bacteria trapped in there?
23:02Good.
23:04Nice.
23:05Sambul done.
23:06That's great, man.
23:07For a big shark,
23:09the tiger has a relatively
23:10weak bite force.
23:12A lot less than the great white.
23:16But on bite alone,
23:18neither of those sharks
23:19can compete with the bull
23:20so far.
23:23It's time to give the great white
23:24another chance
23:25to show the power
23:27of its jaws
23:27and delve deeper
23:30into its attack strategy.
23:33Does the great white's
23:35awe-inspiring breach
23:37make it
23:37the deadliest predator
23:39of all?
23:57This is one of the best places
24:02in the world
24:03to see a great white shark
24:05in action.
24:07Mossel Bay
24:08in South Africa.
24:12Now we're after
24:13the largest
24:14of our three target species.
24:16The granddaddy of them all,
24:18the great white.
24:19Oh, look at that.
24:20Just gonna try to get
24:21the great white
24:21up to the surface
24:22getting them bitey.
24:23So they're not shy.
24:24They're gonna come right up
24:25to the back of the boat.
24:26We're gonna try to lure them
24:27in with some bait.
24:28Gee, man.
24:31Brady will work
24:32with shark expert
24:33Ryan Johnson
24:34to measure the bite
24:35of this bold hunter.
24:38You know,
24:39that's the thing
24:39about a great white
24:40compared to the other ones.
24:41They're very confident,
24:42very charismatic,
24:43big animal,
24:44and they don't mind
24:44coming right up
24:45to the surface,
24:46have a look out
24:46at the water at you.
24:48While at the surface,
24:50great whites spy hop.
24:53They raise their heads
24:54out of the water
24:55scanning their surroundings,
24:57perhaps looking for prey.
24:59Look at it.
25:00Look at it.
25:00Here's the spy hop.
25:01Look at that.
25:03Look at that.
25:06You literally have
25:07to push them off
25:08the motors.
25:08They'll come back here
25:09and injure themselves
25:10on these props.
25:11You gotta be careful, man.
25:13I don't like that.
25:16They're that bold,
25:18that confident.
25:19does that extreme confidence
25:23go hand in hand
25:25with a strong bite?
25:28The bull shark
25:29has set a high bar
25:30for bite force.
25:32It's up to the great white
25:34to beat it.
25:37Brady first measured
25:39the great white's bite
25:40years ago.
25:41I mean,
25:446'6'9",
25:45that is a heck of a bite.
25:48Back then,
25:49he got a reading
25:50that was over
25:51600 pounds of force,
25:53more than the tiger shark,
25:55but less than the bull.
26:01You've got some big sharks
26:02around.
26:02Big sharks
26:03should equate
26:04to big bite.
26:05Those bull sharks
26:06don't get that big,
26:07only about 9 or 10 feet long,
26:10yet do they really
26:11have a bite
26:11that's almost twice
26:12that of a great white.
26:14Today,
26:15we'll clear up
26:15some of that mystery.
26:18Brady wants
26:19to make sure
26:20the great white
26:21really uses
26:22its full force
26:23on the meter.
26:24This time,
26:25he's trying
26:25something new.
26:28Something that we've
26:29talked about
26:29in the past
26:30is that
26:30our bite force meter,
26:32our pressure plate,
26:33is hard and rigid.
26:35It's kind of unnatural
26:36for a shark
26:36to bite that.
26:37Are we really
26:38getting legitimate bites
26:39from that rigid
26:40pressure plate?
26:42So,
26:42I had the National
26:43Geographic Engineers
26:44come up with
26:45what I like to call
26:46the bite bag.
26:47It's much more flexible
26:48and pliable
26:49than our old
26:50rigid pressure plate.
26:52So maybe the sharks
26:53will think
26:53that this is
26:54a natural prey item
26:55and give us
26:56a stronger bite.
26:57Great white sharks
26:59are thought of
26:59as eating machines.
27:01They're actually
27:02picky eaters.
27:04They prefer to prey
27:05on high-fat animals
27:07like seals,
27:08sea lions,
27:09and porpoises,
27:10creatures with soft bodies.
27:13It's a more pliable
27:15thing for the sharks
27:16to bite,
27:17and it's filled with air,
27:19which will give us
27:20the pressure reading
27:21in pounds of force.
27:23So I'd like to retest
27:25the great white
27:25to see if we can beat
27:27that quarter-ton bite force
27:29that I measured years ago
27:31and elevate this animal
27:33where it belongs,
27:35king of the bite
27:35above the bull shark,
27:37but I guess
27:37we're going to find out.
27:39Ryan attaches bait
27:41to the softer bite bag.
27:43The bag's covered
27:44with Kevlar,
27:45the same material
27:46used in bulletproof vests
27:48and chain mail.
27:50The shark will be able
27:51to chomp down
27:52without puncturing it.
27:55Okay, Matt,
27:56we'll get to the guy.
27:56Okay.
27:56Okay.
27:56Shark, shark, shark!
28:13Oh!
28:16Here we go.
28:16Here we go.
28:17Turn, turn.
28:17Come on in, baby.
28:19That is a good one, man.
28:20Oh!
28:21He's biting the motor.
28:28Watch your ass, buddy.
28:38Oh, oh!
28:40Whoa!
28:40Come on, baby.
28:42Got it, got it!
28:43We got a bite!
28:46We got a bite!
28:48Watch yourself.
28:49He's definitely got it!
28:52Oh!
28:53Whoa!
28:54Got you, mate.
28:54Got you.
28:55He's got you.
28:56Are you free?
28:57Yeah, yeah, yeah, yeah.
28:59Woo!
29:00That's a bite!
29:01That's a bite!
29:02Man, pull me in the water, too!
29:05The shark yanked the bait
29:07so hard
29:08it nearly pulled Brady in two,
29:10his legs dangling underwater.
29:15Luckily, Brady's okay,
29:16and the bite bag did the trick.
29:19Yeah, you know what?
29:20It works.
29:20They do not want to let it go.
29:22It's pliable.
29:23They got it.
29:24You still see the bite's got out of it.
29:25Yeah, yeah, look.
29:253, 7, 2, 5,
29:273.0, 3.4, 4.7.
29:31He's down there just giving it this
29:32because it feels like a natural prey item.
29:35He's coming back up.
29:36He's coming back.
29:36I can see him.
29:37He's coming up.
29:37He's coming up.
29:38He's coming up.
29:39When the shark finally releases the bag,
29:42they have a series of bite force numbers.
29:44The biggest is 350 pounds.
29:48350, that's a huge bite,
29:50but it's still not even close to the bull shark.
29:52How long do you think that shark was?
29:54It wasn't the biggest shark.
29:56It was only about 3 meters, 9, 10 foot.
29:58So 9 or 10 feet,
29:59that's about the same size as the bull shark
30:00that gave us a 900-pound bite.
30:03This guy, 350-pound bite.
30:05That's still a huge bite,
30:06but nothing close to the bull shark.
30:08And I'm convinced.
30:10The bite bag is a great new design,
30:12but also the bull shark has the stronger bite.
30:15I mean, that's a big shark.
30:16Nothing even close, though, to 900 pounds.
30:19You know, from my side,
30:20it's a bit disappointing.
30:21Great whites.
30:22A pinnacle shark.
30:23This is what I've had.
30:24It's a pinnacle shark.
30:24Yeah, not so great anymore, my friend.
30:28It's totally unexpected.
30:30The much smaller bull shark is the bite force leader.
30:35But that doesn't mean it's the deadliest predator.
30:40There's another factor that could tip the scales.
30:44Great whites don't usually attack people.
30:47When they do,
30:48their teeth can leave behind a deadly stew of bacteria.
30:53The upper teeth are serrated,
30:56designed for cutting and sawing.
30:57The teeth in the lower jaw are used for impaling.
31:03They're sharper than in the bull or the tiger,
31:06and could help to drive bacteria even further into a wound.
31:15Brady's already collected samples from the other sharks.
31:19That is a monster.
31:21But this time, he'll literally be hands-on.
31:25Come on, big boy.
31:26Say hello.
31:29Brady will try to hold the shark's mouth open long enough
31:32for Ryan to jam in the rubber slug.
31:38Oh!
31:39Oh!
31:39Oh, my!
31:43Here it's going.
31:44She's turning.
31:45She's turning.
31:45She's turning.
31:46Go for it, mate.
31:47That's it.
31:47That's it.
31:48Get out.
31:49Oh!
31:49Oh!
31:51Whoo!
31:52That was close.
31:53It was.
31:54It was.
31:54She's going right for the motor.
31:56I know it.
31:57Nice day this way.
31:58Oh!
32:00That's a good practice.
32:01Yeah.
32:02All right.
32:02Here she comes again.
32:05This is good for us.
32:07Yikes.
32:08That's a big one.
32:09That's a big shark.
32:10This is the one we want.
32:11That is just a massive animal.
32:13Look, look!
32:13Oh, yeah.
32:20Yeah.
32:21Get it in there.
32:22Get it in there.
32:22Whoa, whoa, whoa.
32:22Watch your feet.
32:23Watch your feet.
32:23Watch your feet.
32:27Whoa, whoa, whoa, whoa.
32:29Whoa!
32:30Coming straight up.
32:31See that?
32:34See that maw?
32:35That thing is this big.
32:37Whoo!
32:38Man, you talk about looking death right in the face.
32:40Gosh.
32:40Oh, my God.
32:41You can't get much better than that.
32:42Whoo!
32:43Oh, I'm up there, yeah.
32:48The great white shark bacteria are analyzed,
32:51along with the other samples.
32:53They're put through a series of tests,
32:56and after weeks of waiting, the results are in.
33:02They confirm what other studies based on dead sharks have shown.
33:07The jaws of all three species are crawling with dangerous germs.
33:11bacteria found in these sharks are known to cause serious wound infections, and potentially deadly illnesses, including septicemia, diseases that could land you in intensive care.
33:25Worse, the tiger and the bull, in particular, have bacteria that are resistant to many antibiotics, making them even more dangerous, and the bull's bite force is the strongest.
33:39Oh, that puts it up there with the biggest biters on the planet, but the great white could still be the deadliest predator, thanks to the unique way it catches its prey.
33:52Oh, we got two of them.
34:10Great white sharks may not have enough bite force to compete with the bull shark, but maybe they don't have to.
34:23Here in South Africa, Brady's investigating the great white's reputation as a fierce predator.
34:44It's not just the force of its bite, it's how it bites.
34:52They launch themselves like missiles, charging at seals at speeds of up to 15 miles an hour.
35:02Does the breach give great whites the deadliest attack of any shark?
35:07Here at Seal Island, Brady intends to find out.
35:15More than 4,000 Cape fur seals live in this area.
35:23And this rocky terrain is their preferred breeding ground.
35:28They have few natural predators here, other than the great white shark.
35:33Do you think it's the low light levels that makes it feel harder to see the sharks?
35:39Yeah, you know, these seals, if they see a shark, they're really flossing to get away.
35:44So the shark has to get every advantage we possibly can.
35:50Cape fur seals are quick, agile swimmers.
35:53To keep up, the great white uses the element of surprise.
35:57They ambush from below.
36:09And use short bursts of speed to close in.
36:14It's hard to get close to these attacks.
36:18But Brady's hatched a plan to bring the breaches to him.
36:21You and I have both seen a lot of breaches.
36:24But, you know, it's hard to really see what's going on.
36:27We're on the back of the boat.
36:28The boat's up and down.
36:29We have swells.
36:31But I think we may finally solve that problem.
36:35I've brought some friends with me.
36:37Some high-tech friends, and they've got some high-tech gear.
36:39Bobby Watts is a world champion remote control helicopter operator.
36:45Eric Van Giesen is an expert in remote control cameras.
36:50They're going to give us a new perspective on shark breaching.
36:54Just by looking at this thing, Bobby, I can tell this isn't off the shelf.
36:58I'm not going to walk in my neighborhood variety store and just pick this thing up and walk out, right?
37:03No, I don't think so.
37:04This is a pretty highly customized machine we've got here, made out of lots of carbon fiber and, you know, a lot of low-weight, high-strength material.
37:15It's like a real full-size helicopter.
37:18Exactly. It flies just like a big one.
37:20We can hover with it. We can go forwards, backwards, sideways.
37:23The high-angle footage will be transmitted back to the boat.
37:27Instead of just getting that shot that we've all seen from the back of the boat, we can have an eye in the sky.
37:32This thing can hover right over the decoy. It can circle it. This is going to answer the questions we've got.
37:39Bobby and Eric take the helicopter for a test run.
37:45Oh, look at that. That's awesome.
37:48They want to make any adjustments now, not when there's a shark breaching.
37:53Even with the rocks, you know, I can kind of see it.
37:57Go backwards, forwards, side to side.
37:58Yep. Sideways.
37:59Yep.
38:00Any orientation you want.
38:02Bobby's practicing working this close to the open water.
38:06Careful, you got about 100,000 birds over here to your left.
38:09OK.
38:11The seabirds flying nearby could be a complication.
38:14How high can you go up? Can we get a good aerial?
38:16Yeah.
38:17The helicopter will go as high as you want it to, to tell you the truth.
38:21Wow.
38:22As high as you can see.
38:23Really?
38:24So it's got that kind of range.
38:25Yeah, that kind of range.
38:26Literally out of sight.
38:27So it will report everything that it sees.
38:28I mean, how high is that right there?
38:30That's probably a few hundred feet.
38:31A few hundred feet?
38:32That's plenty high enough, my friend.
38:33Like I said, we can take it till it's a dot in the sky.
38:35OK, then can you come right to us?
38:36Yes, I can.
38:38The helicopter flies without a hitch.
38:42We can see it, Brady.
38:43If everything goes according to plan, it'll capture breaches in an amazing new way.
39:03Awesome.
39:13The sun has just started to rise.
39:29The great white sharks are coming out to feed.
39:34The team's remote control helicopter is fully equipped to capture shark breaches off the coast of South Africa.
39:42It's a tough assignment.
39:47So we're good for a 16-minute flight.
39:51Brady and the team aren't taking any chances.
39:55They've picked an area known for shark activity.
39:59They've got experienced operators at the controls of the chopper and the camera.
40:05And to trigger a breach, they'll drag a sealed decoy behind the boat.
40:11All right, decoy's in.
40:17It's getting to be the time that the sharks start trying to hunt the seals.
40:21Now it's just a waiting game.
40:22Get our helicopter in the air and tow it around Seal Island.
40:26Keep our fingers crossed.
40:28Bobby, the pilot, and Eric, the camera operator, get the helicopter into position.
40:34When a shark reaches, they want to be right on it.
40:40Oh, that's...
40:41If you can keep that angle right there, that's money.
40:43Like that?
40:44That's cool.
40:45Yeah.
40:46The more over it you can get, the better.
40:48Oh, that's just great right there.
40:50Come on.
40:51Bite, sharks.
40:52Bite.
40:53Great whites are solitary hunters that generally feed in the early morning.
41:06Shark, shark behind it.
41:10He's following it.
41:11The water is teeming with activity.
41:17But so far, no breaches.
41:20Did you see that one?
41:22I'm sure he looks like he's pretty far back.
41:27They need to change the chopper's battery in the next couple of minutes, or it will drop into the drink.
41:32But just when Bobby's about to turn it around...
41:41Woo-hoo!
41:43Nice!
41:44That was a good one.
41:45Unbelievable.
41:46Fully out of the water, man.
41:48He got it.
41:49It looked like he team-moned it.
41:50It looked like a marlin coming out.
41:52That is incredible.
41:53Yet it was probably a one-ton animal.
41:56That's the biggest predatory fish in the sea.
41:58And that has got to be the most impressive predatory tactic I have ever seen.
42:06Woo-hoo!
42:09The great white shark smashes into the decoy with the full force of its body.
42:15Its massive jaws open wide for the bite.
42:20The combination of brute force and a razor-tooth bite gives the great white a uniquely deadly one-two punch.
42:28Man, no question what happened that time.
42:30I mean, look at this massive bite.
42:32If this would have been a real seal, that would have just been a massive injury.
42:36It would have taken off half of its body.
42:39It would have been almost death instantly.
42:42On top of that impact that blew the seal out of the water.
42:46That is awe-inspiring.
42:48Many have thought of breaches as unstoppable assaults.
42:54But the helicopter footage suggests something else.
42:59Watching from behind the dorsal fin, this shark appears locked onto its target, poised for an attack.
43:06Then, amazingly, it veers away.
43:12It seems that great whites have the ability to call off an attack.
43:20Maybe their breaches are more calculated than anyone knew.
43:24Still, these attacks don't always go as planned.
43:33I don't think that they're exploding out of the water and always getting that seal in their teeth.
43:38Even when the shark doesn't nap the seal, is it so powerful, roaring up from below, that the impact alone can stop its prey?
43:57Brady will do one last test.
44:00To find out how hard the great whites can smash into a seal.
44:07This little device is called an accelerometer.
44:11It measures force.
44:12It's going to allow us to determine how many G-forces the shark hits the decoy with.
44:18I'm going to put it inside and throw her overboard.
44:24The helicopter takes to the skies again.
44:26It's camera aimed at the decoy.
44:33Oh, man, it's perfect. Stay there.
44:37The great whites' feeding time is almost over.
44:41But before the team calls it a day...
44:49Oh, yeah, baby!
44:51I nailed it!
44:52Oh, that was awesome!
44:53He got it so good.
44:55It was right in the middle.
44:57Man!
44:58And that shark just exploded out.
45:00Completely cleared the water.
45:02It had to be a 10, 11-foot shark.
45:04Man, unreal.
45:06Can't wait to pull the decoy in and let's get our data.
45:08Man!
45:09Awesome!
45:11Celebration flyby!
45:14Is that what that is?
45:16Oh!
45:17Look at that.
45:19Oh, my God!
45:20Look at that.
45:21He cut it in half.
45:22My heart just stopped.
45:25Because I thought the accelerometer was gone.
45:27But we still got it.
45:28It's still in there, I think.
45:31Yeah, we got it.
45:32It's still in there.
45:33We got the accelerometer.
45:34Look at that.
45:35Man, this is a big shock and a big butt.
45:38Whoo!
45:40The accelerometer shows a reading of 50 Gs of force.
45:45Race car drivers tearing around a hairpin turn may face up to 5 Gs.
45:50And fighter pilots screaming through the skies can experience 9.
45:57For a young SEAL, those 50 Gs would likely stun it, even knock it unconscious.
46:02The breach may be designed to deliver blunt force trauma, not just a lacerating bite.
46:11Oh!
46:12Holy !
46:14That was the best we've ever had!
46:17The great white shark has put on an impressive display.
46:21But is it really the shark with the deadliest attack?
46:23For Brady, the answer is yes.
46:27Based on these tests, the bull has a powerful bite force and dangerous bacteria.
46:33989!
46:35989 pounds!
46:37While the tiger can bite through turtle shells.
46:42But when it comes to an all-around assault, the great white seems to stand alone.
46:46The deadliest of these sharks.
46:52And the ultimate ocean predator.
47:09Merci.
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