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Documentary, Smart Sharks Swimming with Roboshark David Attenborough
Are sharks robotic killing machines or intelligent animals, capable of complex behaviour? Roboshark, an animatronic shark with a camera is used to film the behaviour of sharks.
#DavidAttenborough #Sharks #SwimmingSharks
Are sharks robotic killing machines or intelligent animals, capable of complex behaviour? Roboshark, an animatronic shark with a camera is used to film the behaviour of sharks.
#DavidAttenborough #Sharks #SwimmingSharks
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AnimalsTranscript
00:27If there's one animal
00:28that can strike terror in us,
00:31it's surely the shark.
00:35So, brace yourself for an intrepid journey into their domain,
00:40closer than ever before,
00:41to witness spectacular shark behaviour.
00:49We'll penetrate the heart of shark packs,
00:54drift with giants,
00:58and meet some sharks rarely filmed before.
01:08Sharks are often portrayed as mindless killers,
01:13little more than swimming robots
01:14driven by a primitive, pre-programmed brain.
01:20But are they, in fact, more intelligent than we think?
01:24To find out,
01:25we're going to introduce some sharks
01:27to a shark of our own.
01:30Meet Robo Shark.
01:33Come on, come on.
01:39Robo Shark is at the cutting edge of wildlife filmmaking.
01:44He's a free-swimming animatronic shark,
01:47controlled with underwater signals
01:49which he picks up with a receiver on his back there,
01:53designed to look just like a fresh-and-blood shark.
01:56His mission is to go among wild sharks
02:00and discreetly film their behaviour
02:02using this camera hidden here in his nose.
02:07Off you go.
02:11Robo Shark is a brave pioneer
02:13and a unique experiment.
02:15He's going to get closer to the sharp end
02:18than any diver dares.
02:21What real sharks will make of him, we've no idea.
02:25But their reactions may provide new insight
02:28into how a shark's mind really works.
02:31So, what will Robo Shark reveal
02:34about the intelligence of these fearsome predators?
02:37Will they be smart enough to blow his cover?
02:40And if it turns out
02:42that sharks are more intelligent than we thought,
02:45will that defuse our fear?
02:47Or is a smart shark the most terrifying shark of all?
02:52Let's follow Robo Shark to find out.
03:09Robo Shark's first assignment
03:11takes him to a unique corner
03:13of the South Pacific Bikini Atoll.
03:23This lagoon is a graveyard of scuttled warships.
03:27Evidence of an explosive past.
03:37In the late 1940s,
03:39the United States tested nuclear bombs here.
03:42and the area is still contaminated.
03:45Fishing has been banned for more than 50 years.
03:49This has created a unique shark paradise.
03:57It's Robo Shark's first test in the field.
04:00So, will he sink or swim?
04:14The air grey reef sharks travel in large aggressive hordes.
04:18So, how will they react?
04:32Their repeated charges and displays of their pectoral fins
04:36show they feel agitated.
04:40But if they thought this really was a larger shark,
04:43they'd keep their pistols.
04:45Instead, they nose bump to investigate him.
04:57So, these sharks are too smart to be fooled by Robo Shark.
05:05But other fish like this Remora aren't.
05:08Remoras shadow sharks hoping to hoover up their leftovers.
05:15The question is,
05:17what makes sharks more intelligent than many other fish?
05:23We begin our investigation into shark intelligence
05:26by looking at the basic elements that constitute a shark.
05:33Out of the over 450 shark species,
05:37reef sharks are the classic prototype
05:39that's the basis of Robo Shark's design.
05:50A shark is perfectly streamlined to cut through water.
05:54It's covered in tiny interlocking plates called denticles.
05:59Each one is ridged to break down water turbulence
06:02and minimise drag.
06:04So, sharks swim smoothly and in silence.
06:09But there's much more to sharks than meets the eye.
06:12They're armed with an astonishing array of supercharged senses.
06:18They can detect a single drop of blood
06:20in 25 million drops of seawater.
06:26They hear low frequency sounds
06:29from more than a mile around through their inner ears.
06:34They have a line of pressure detectors down each flank
06:37that detect movement
06:38and give the shark a 3D map of its surroundings.
06:44In low light,
06:45shark eyes are ten times more sensitive than ours.
06:48And sharks can detect the electrical impulses
06:52that are generated by all living things
06:54down to just five billionths of a volt.
06:57So, it's hardly surprising
06:59that sharks are among the most successful predators in the ocean.
07:03Who's of a human being.
07:32They're having a hard drive of ground.
07:33No, no, no.
08:01But are hunting sharks driven by simple instinct,
08:05pre-programmed to respond predictably to cues from fleeing fish?
08:09Or are they capable of more than that?
08:14For his next mission, RoboShark meets one shark that is thought to be far more intelligent.
08:28We begin exploring shark intelligence by looking at brain size.
08:32Some sharks have relatively large brains,
08:35which in terms of body weight ratio are on a par with those of dogs.
08:41Here's one of the biggest brains of all, the notorious great white.
08:48This young female has a brain 45 centimeters long.
08:52Its structure is quite different to a mammal's brain,
08:56and we're only just beginning to unravel its complexity.
08:59It was believed that 70% of it was dedicated entirely to smell,
09:04but new research has revealed a highly developed cerebrum,
09:08thought to be responsible for learning, memory, and thought.
09:16So, great whites do have the brain power to be sparked.
09:25And this one's curiosity could well be evidence of that.
09:34Curiosity goes beyond instinct.
09:37It's the starting point of exploring and learning.
09:49Amazingly, she's wary of RoboShark.
09:54She seems smart enough to know that some encounters can be dangerous.
10:06The shark is inquisitive, and goes in to investigate.
10:07These are giant petrels off southern Australia,
10:10another novelty to an inexperienced young shark.
10:22The shark is inquisitive and goes in to investigate.
10:36These bird brains seem unaware of any danger.
10:54Its curiosity turns into feeding mode.
11:01But its first attempts are frustrating.
11:04Its own bow wave pushes the petrels out of harm's way.
11:18But over the next two days, the shark modifies its strategy.
11:23Now it rushes upwards at a steeper angle.
11:38By learning through trial and error, the shark succeeds.
11:41In fact, sharks can learn 80 times faster than cats.
11:45But can they remember what they've learned?
11:52In fact, sharks can learn 80 times faster than cats.
11:53RoboSharks in Belize to investigate the memory of the largest fish in the sea.
12:03A kilometre down, giants are on their way.
12:14Whale sharks.
12:18They migrate thousands of kilometers along this coastline at huge depths.
12:26Down here, the immense pressure would crush RoboShark.
12:40But our spy has a tip-off that the whale sharks are about to come up for a rendezvous.
12:48And once again, they're right on cue.
13:00At the same time each year, they gather at a specific offshore reef.
13:11More whale sharks arrive, all young males, around 25 of them.
13:27But why come to the surface now?
13:34They're drawn to a spectacular feast, hosted by snappers.
13:44Once a year, they come together, and in late afternoon, as the full moon rises, they start to spawn.
14:33The snapper's reproductive frenzy provides a high-protein blowout,
14:39one of the most important things that it's past.
14:39are the highlights of the whale shark's year.
15:01The whale shark is a giant filter feeder.
15:08Its massive throat and gill muscles create a suction pump
15:12that sieves spawn-filled water over the filter plates in its gills.
15:27For a week, the sharks gorge on this short-lived food source.
15:38Unlike salmon, for example, which return instinctively to their birthplace following chemical clues,
15:44somehow these sharks learn where the snapper are
15:47and then remember to come back to this exact location each year.
16:03The snapper are finally spent and return to the reef.
16:17And the satiated sharks descend back to the depths to continue their migration.
16:31So, if sharks can turn up for one annual event,
16:35could they remember several such appointments throughout the year?
16:38Do they have a more complicated long-term memory?
16:47Robo sharks embarking on his riskiest assignment yet,
16:51gate-crashing a gathering of one of the world's most predatory sharks.
17:07Tiger sharks will migrate thousands of kilometres to take part in an annual feast.
17:18The tigers home in on the nesting grounds of green turtles.
17:26Every summer, the turtles meet at the same shallow reef to mate.
17:37This year is a stranger in their midst.
17:47Robo shark looks real enough to this green turtle.
17:53In defence, it turns its armoured back
17:56and swims away from the shark's jaws to its safer tail end.
18:28As the sun goes down
18:30the female turtles start to lay their eggs on the nearby beaches, and in the
18:38water hungry sharks are waiting.
18:46Tiger sharks.
18:53For the turtles hauling themselves up and down the beach is an enormous effort.
19:08Once back in the water they're exhausted and easy targets.
19:17Air-breathing turtles must visit the surface, but there they're exposed to ambush from below.
19:41A turtle is too big to swallow whole, but tigers have serrated teeth that soar right through
19:48the shell like a can opener.
19:56More and more sharks arrive.
20:00Tiger sharks will normally eat almost anything, including smaller sharks.
20:05But right now they're completely focused on the turtle.
20:17A tiger's bite exerts a pressure of around two and a half tons per square centimeter.
20:24The turtle's shell cracks like a china plate.
20:38Our spy has swum with one of the ocean's most deadly sharks.
20:42And once again, he's survived to tell the tale.
21:02It seems that sharks may have a timetable of banquets that are some thousands of kilometers
21:08apart, from turtle rookeries, to monk seal pups, and albatross nesting sites in Hawaii.
21:23Here, tiger sharks arrive on cue for the four-week period when the chicks begin their maiden flights,
21:31which are often their first and last.
21:42But how do sharks navigate between these widely spaced meals?
21:47Could they use memory maps?
21:52These maps probably include visual landmarks.
21:57They may also be directed by the corridors of scent that crisscross oceans.
22:03They may even use their electro-receptors to pick up the Earth's magnetic field.
22:10Like a GPS, could this help them to compute exactly where they are?
22:15As yet, we just don't know how exactly they navigate.
22:29So, sharks track down precisely timed feeding opportunities.
22:34But they also keep daily appointments for different reasons.
22:42At dawn, this snub-nosed monster emerges from the depths.
22:49It's the pelagic thrusher shark, named after its long, thrashing tail.
23:01In the Philippines, it leaves the deep sea trench each morning to explore the shallow coral reefs.
23:21Much of this reef has been dynamited by fishermen and is dead.
23:38The sharks search for the last few outcrops of living coral.
23:45But it isn't food that draws the thrashers here.
23:49They're visiting the cleaner wrasse, who spend much of their lives grooming a range of other fish.
23:59The three-meter-long Thresher lowers its pectoral fins and slowly circles.
24:07Cleaner wrasse catch up and start work picking parasites from the shark's skin.
24:12It's too late for tourism.
24:13How many sharks do you know that there are other fishmores?
24:18While they're gonna be the only ones who have seen the shrimp,
24:27where they have seen the fishmores...
24:30The reef fishmores are far more than anything.
24:38trip to come back here every morning, which seems to be evidence of organized thought.
24:52The cleaning stations are a natural meeting point,
24:55an unusual situation for these nervous deep-sea loners.
25:02But can sharks be social? And if so, how do they communicate?
25:08Social behavior is another way to see how smart sharks really are.
25:19Another client for the cleaning station, a scalloped hammerhead.
25:24Named after its extraordinary scalloped head,
25:27is thought to have one of the largest brains of any shark.
25:36Like thresher sharks, the hammerhead slows down for cleaning and adopts a special posture.
25:58Unlike solitary thresher sharks, hammerheads gather
26:02in shoals that are sometimes 500 strong.
26:25But unlike a typical fish shoal,
26:29the hammerheads only meet up during the day for what seems to be social reasons.
26:40This head shake or shimmy dance is a bullying tactic.
26:46Dominant females use it to force smaller females to the outside of the shoal.
26:52The top female hangs on to center stage, which may help males to pick her out.
26:58These battle scars may show she's recently mated.
27:05They're made when the male bites during copulation.
27:13Researchers have so far identified nine distinct postures,
27:18but there may well be other more subtle signals that we haven't yet detected.
27:27The head shaking creates pressure waves in the water, perhaps another way of getting messages across.
27:34In its simplest form, communication is instinctive,
27:38but in the hammerhead's dynamic hierarchy, it seems much more complex than that.
27:46If this is true, can sharks team up to solve a shared problem such as finding food?
27:57Here in Western Australia, bronze whalers do appear to work together to herd shoals of anchovies in shore.
28:08But whether this is really teamwork or just competition,
28:13is still hard to say.
28:15To find out more, let's see these social sharks at work during the highlight of their feeding calendar.
28:29This time, RoboShark is braving stormy waters to report back on one of the most dramatic natural events on Earth.
28:47This time, RoboShark is a very important event on Earth.
28:48Each June, millions of sardines head north up the coast of South Africa,
28:52eating the plankton nourished by a seasonal current of nutrient-rich cold water.
29:12The sardine run creates an immense slick up to 30 kilometers long.
29:23Bronze whalers are attracted in their thousands,
29:26with a multitude of other predators, including common dolphins.
29:37These sophisticated mammals are known to hunt together and to use complex communication.
29:50The dolphins buzz RoboShark with ultrasound.
29:56But it seems he's just a distraction, and they move on.
30:01Following close behind are the bronze whaler sharks.
30:07Sharks are believed to eavesdrop on the dolphins' calls and shadow them to the feeding grounds.
30:16Once there, the dolphins start to chase the sardines to the surface,
30:20driving them together into a bait ball.
30:44Another diner joins the fray, a brooder's whale.
30:57The sardines are within range of yet another predator, caped gannets.
31:04The plunge-diving gannets create infrasonic booms.
31:14His cacophony of sounds draws in the sharks.
31:29Our sardines...
31:48The plunge-diving gsees of ful ongoing Gennels.
31:50The plunge-dying gnom, the sardines.
31:50avoid the shark's front end.
31:58The dolphins work together to corral the sardines
32:01into ever tighter balls.
32:03They appear to blow curtains of bubbles
32:05to help trap the shell against the ocean's surface.
32:15This technique called bubble netting
32:17involves the dolphins playing different
32:19yet highly coordinated roles.
32:32But are the bronze whalers doing the same?
32:34They can't blow bubbles
32:36but they do appear to operate in a loose group
32:39to push the sardines upwards.
33:17But it's kind of hard literally
33:19the sailors being in league
33:20The sharks seem to stick close enough together to create a moving wall,
33:26which may help them to trap the sardines.
33:29They do appear to hunt cooperatively.
33:36So, as well as a phenomenal range of super-tuned senses,
33:40it seems that sharks have some degree of intelligence.
33:45But how smart are so-called man-eaters?
33:48Robo-sharks' next set of missions is to meet them and find out.
34:04First on the hit list is the bull shark, number one shark man-eater.
34:10Bull sharks live in shallow seas and estuaries across the tropics,
34:14where they come into contact with humans more than any other large, powerful shark.
34:22What makes them extra dangerous is that they can also survive in fresh water.
34:28Robo-shark is on a reconnaissance in Africa.
34:30He's travelling upriver to try and make contact.
34:39In the murky water, bull sharks are able to navigate
34:43because they have acute hearing and sense of smell.
34:46They're likely to spot Robo-shark long before he sees them.
34:55And in this world, sharks have deadly competitors.
35:04Nile crocodiles.
35:10So far, the bull sharks are proving elusive, but they're more active at night.
35:35Robo-shark has entered enemy territory and stumbles on a carcass.
35:43Crocodile kill.
35:45There are documented fights between bull sharks and crocodiles,
35:49sometimes to the death.
36:12This time, our hero had to admit defeat.
36:18But he's not beaten yet.
36:20There is another place where contact with bull sharks is guaranteed.
36:32After a few repairs, Robo-shark is back in business.
36:49At last.
36:51But what will this quarter-ton tough guy make of our fiberglass weakling?
37:05The bull sharks seem unmoved by our spies' presence.
37:09Again, perhaps they're not fooled.
37:14Part of what makes these big, powerful sharks so terrifying
37:17is that they're comfortable in very shallow water
37:20where most attacks take place.
37:28Here, they've learnt to turn up at the right time in the right place
37:31to get food.
37:36Gary Adkisson has been feeding bull sharks for more than ten years.
37:41He knows them individually and believes they have their own personalities
37:45and that they recognise him, too.
37:51The sharks bite and jostle each other to get to the food.
37:54Perhaps they see us as competitors, too.
38:02Experts also think most shark attacks are accidental,
38:05perhaps in murky water,
38:07or warning when a swimmer blunders into the shark's personal space.
38:34winded Robo-shark calls time-out.
38:37Winded Robo-shark calls time-out.
38:41Winded Robo-shark calls time-out.
38:42But swimmers in the shallows aren't the only ones at risk from big sharks.
38:56around 40 percent of shark victims are surfers in temperate zones they share the offshore waters
39:04with perhaps the most notorious of all sharks the great white in the vast majority of cases
39:13the shark ignores the surfer but there's always going to be the odd occasion when it doesn't
39:19since whites have such acute eyesight many researchers now doubt the old theory that
39:25they mistake surface for seals the rare attacks are now attributed not to predation but to that
39:32first marker of intelligence curiosity one thing is that inquisitive great whites are tempted to
39:40give chase much as the dog will chase a passing car
39:53the fact that 70 percent of white shark attacks aren't fatal seems to back up this idea so shark
40:03attacks remain extremely rare and seem to be more about curiosity and competition than
40:18predation in the kelp forests off the Cape of South Africa robo sharks ready for his final and most
40:25risky mission he's here to find out where the smart sharks really do learn and adapt to help them catch
40:34their natural prey
40:43they seem unsure what to make of robo shark
40:46they seem unsure what to make of robo shark
41:10but suddenly the real thing
41:13the real thing
41:27each winter groups of a dozen or more great white sharks move in and hold the colony under siege
41:35it's one of the most concentrated population of great whites in the world
41:46but agile Cape fur seals are no pushover and the sharks need all their skill and their intelligence to catch
41:54them
41:58to find their own food the seals must go as far as 50 kilometers out to sea
42:04at first light they prepare for the journey
42:10the larger more experienced great whites know where the best ambush sites are
42:15as far as 32 meters down they silently patrol a hunting zone around the island waiting for the silhouette of
42:22passing seals above
42:28the seals have no choice but to bunch together and make a break for it
42:33the seals have no choice but to bunch together and make a break for it
42:33the seals have no choice but to bunch together and make a break for it
42:33the seals have no choice but to bunch together and make a break for it
42:40the seals have no choice but to bunch together and make a break for it
42:43the seals have no choice but to bunch together and make a break for it
42:54But now a real shark that spots the seals.
42:58And this is when a lifetime of investigation, trial and error,
43:03memory and even teamwork has to come together.
43:14Now the shark has singled out an individual seal
43:17and rockets from the depths at up to 50 km an hour.
43:38Attacks like this require enormous skill, and about half are unsuccessful.
43:45With each minute that passes,
43:47it's more likely that the agile seal will escape.
44:08So for the shark, the pressure is on to make a massive clean first hit.
44:14Individual sharks seem to develop their own strategies.
44:19Some use the vertical explosion.
44:41Other sharks approach their victim horizontal.
44:59This ability to modify and specialise their attack strategy
45:04is clear proof of Great White's intelligence.
45:10But they can still lose their fresh kill.
45:16Great White's appear to travel in loose groups of five or six,
45:20and they're quite happy to gazump another's prey.
45:29But there does seem to be a kind of social pecking order.
45:43Jaw gaping and pectoral fin lowering are well-documented signs of dominance,
45:48a way of enforcing the social hierarchy.
46:03But there's one shark in these waters that definitely doesn't fit in.
46:13Robo shark is way out of his depth.
46:16He's in the danger zone.
46:22The Great White's curiosity has been aroused by his strange signals.
46:26And just as with surfers, this soon leads to a more jaws-on investigation.
46:33and that's the best to do with your human race.
46:38Even then he's not done right after a modern game.
46:42And we'll wait until after a while.
46:44We'll call him the Resistance of the Earth.
46:48We'll call him the threat of the Earth.
46:48And a disinfectant.
46:49You'll call him.
46:49Unless he's in the race.
46:50We'll call him theEVM.
46:53We'll call him the ship in sight.
46:54And the data is his name.
46:55We're calling him the intranser than the north.
46:55But he'll call him the sky.
47:03I'll give him the police.
47:07RoboShark has paid the price for spying on the biggest of the predatory sharks, and perhaps the smartest one of
47:15all.
47:23He's given us new insights into shark behavior.
47:27Researchers are writing a scientific paper on his shark encounters.
47:31But for now, his work is done.
47:42RoboShark was only a machine, but we're now killing flesh and blood sharks in unprecedented numbers.
47:48At least 100 million die each year, either caught accidentally or slaughtered deliberately to be made into shark fin soup.
47:5975% of threshers are now gone. Experts fear the worst for many shark species.
48:10The shark's success has always been accredited to their superb design, but it's down to brain power, too.
48:18Perhaps a smart shark would be easier for us to care about.
48:22But if we push them to extinction, we'll never know how smart sharks really are.
48:31We'll be right back to you.
48:32Here we are.
49:00Transcription by CastingWords
49:12CastingWords
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