Original subtitles

How often are you given the opportunity to repeat a fantastic experience and

have it be even better the second time around?

This is my return trip to a volcano.

A volcano erupting with sharks.

I'll be diving to my limits, looking for seven species of sharks in seven days,

including a deep water mystery.

Dive with me to Shark Volcano.

This is Cocos Island.

In my view, one of the last truly pristine places in the world. It's 300

offshore of Costa Rica.

And two and a half million years ago, none of this was here. Then a volcano

erupted, and this is the peak of the volcano.

Now, it's a tropical rainforest that gets 24 feet of rain each year. But if

think that's lush, you should see what's underneath.

Now, imagine a volcano sticking out in the middle of the Pacific Ocean.

Cold currents are coming by, bringing nutrient -rich water up to the top.

which is incredibly productive and supports an extraordinary amount of

And that is what we're interested in, showing you what is underwater.

Cocos Island supports a huge variety of life, a lot of different types of

animals as well as a lot of numbers.

And with that kind of variety, I'm not sure exactly what we're going to be

seeing. But this, I can assure you, we will be seeing a lot of dark.

The reason so many sharks come here is because Cocos is like a truck stop in

sea. There's plenty of food and good shelter.

It's an oasis in a watery desert, and the life it attracts is why I'm so

to come back.

I first came to Cocos Island 12 years ago. Even then, I recognized that this

place was special.

But I hadn't realized just how special.

I knew there were a lot of species of sharks in Coco's, but I had only come

across three or four on my first trip.

This is shark heaven.

Among the top sharks you might find here are the frenetic white tips, the bold

and beautiful silver tip, and of course, the mighty hammerhead.

There's also that great mystery about a deepwater shark, which has been seen

living in these waters, but it's never been filmed.

So we're going to give it a try by diving deep.

And to bring that to you, we've got some pretty special equipment.

Starting with this, of course. We have two of these. This is a high -definition

camera. We've got another one here.

To dive, we've got a lot of fun toys. We've got semi -closed and fully -closed

rebreathers. Normal scuba gear consists of a tank of compressed air. Nothing

fancy. You just breathe it away in about an hour or so. Then you have to return

to the surface.

But with a rebreather, you reuse the air you breathe. It's cleaned by a special

element called a scrubber, which removes carbon dioxide and it automatically

adds oxygen as needed.

With a rebreather, you can stay down much longer and it's quiet.

Great for getting close to sharks.

see Mark dealing with his scrubber over there right now. But basically, these

rebreathers allow us extended bottom time as well as the ability to safely go

very deep. We're going to be talking more about them later.

But we also have this.

This is a helmet.

This helmet allows me to sit in a room not a very... large room, mind you. It's

only slightly larger than my head. Nevertheless, I'm very comfortable in

breathing air. It all comes down through this big umbilical cord. So we have two

-way communication plus cameraman can hear me. So this bit of technology

us to do what we're going to do now.

And that is to find some sharks.

They say that big surprises come in small packages.

And that certainly is the case with our first shark, the reef white tip.

Reef white tip sharks seem to have a split personality, which you will soon

clearly witness.

But we'll start with the easy part, midday.

Let's have a look. You may be wondering why I'm appearing so irresponsible in

walking all over the coral.

It's because all the coral here is dead.

I'll tell you more about that later.

It obviously doesn't affect the fish population.

There are huge schools of fish swimming everywhere.

But the reef white -tip sharks are found right on the sandy seafloor.

I wanted to get a nice, cozy shot with these sharks.

It soon became clear that would prove difficult.

No wonder they wouldn't lay still with a stumbling beast crashing nearby.

Eventually, we found one that looked like it may put up with us.

Who said this job was easy?

Hocus Island supports an enormous...

a population of reef white -tip sharks.

And you can see their daytime behavior is rather lazy.

They're not slowly swimming like these above.

They're laying on the bottom, taking a rest, generally in little sandy patches

in reef areas like this.

And this is the reason we wanted to get close, because now you can see those

little cleaning fish popping in and out of the gills.

This is a full -service truck stop.

Reef white -tips.

exhibit this kind of behavior in the daytime.

They don't do much. They just kind of slowly move around, swim in small

and lay in the sand. Now, most sharks have to continue swimming in order to

breathe. They sink, and they can't get any water over their gills. Therefore,

they suffocate and die.

Reef white tips.

See us now, puppy.

That's a trick that they can do that most sharks cannot.

They physically pump water over the gills so they can get oxygen to change

at rest.

Now, speaking of rest, that's what's going on here.

Three -point tip sharks are like Dr.

Jekyll and Mr.

Hyde. In the daytime, they're laying around, swimming in slow circles, not

much at all.

But believe me, this guy lives on the night shift.

We'll see this animal performing a very, very different behavior.

It might seem a little bit unusual for me to be walking around the bottom like

this.

Normally, I wouldn't do that on a coral reef, which is exactly what all of this

used to be, until El Niño came to town.

Warm water has moved into Cocos Island and basically killed all of this coral.

Unfortunately, this once thriving coral reef has now rendered algae -covered

rubble.

Another problem they have is this.

This is crown -of -thorn starfish.

Occasionally, these crown -of -thorn starfish will have a population

When that happens, these things are everywhere.

And guess what they eat?

You got it.

Coral. So what this one is doing, it's creeping onto this little bitty coral

head right here, which is called parietae.

It exudes its gut. It takes its gut out of its body, covers the coral, digests

it. then brings the gut back in and crawls away all after a day or so,

nothing behind but a bleached -out, white, dead skeleton.

Many years ago, these crown of thorns were thought to be the bane of the

Everyone hated them, and divers were going in and cutting them up in pieces.

Bad idea! Guess what?

You cut this in half, and it makes two.

and that's what we're going to do.

Take a look at this.

Right out beyond me, it looks like the sand flats need a bit of a haircut.

Well, all of these little apparent bits of foliage are actually

fish. More specifically, eels, garden eels.

If you look out there, it looks like a garden of eels.

They live in a burrow, which they dig with their tail.

When danger comes, watch.

Boom!

Away they go.

Down in the hole, safe as they can be.

Beautiful creatures, aren't they?

And right on cue, a black -tipped shark perfectly illustrates our point. See

them disappear near the shark?

And once danger has passed, they come right back up again.

Our only danger was running out of air.

It was a relief to see so many reef white -tipped sharks around Cocos,

it wasn't like that on my last trip 12 years ago.

Back then, there was ruthless fishing near the island, which killed many of

these magnificent fish.

Sometimes, just their fins were cut off to make shark fin soup, and their living

bodies dumped overboard.

Thankfully, Cocos is now a well -protected marine nature reserve with a

exclusion zone, and it appears to be working.

The only boats near Cocos today are dive boats.

and the money we pay for the dive permits goes toward the conservation

In order to film the Jekyll and Hyde nature of White Tips, we'd have to go

in the water for a night dive.

Along a shallow reef on one side of the island, there was one place where we'd

been told they'd come in their hundreds.

White -tipped sharks are not scary in themselves, but at night, they

hunt in packs and become quite a different kettle of fish.

Diving at night is very different to daytime diving.

Coordinating a film crew is nearly impossible in the dark, and you have to

carefully plan the dive before you get in the water.

On the way down, it appeared as though the bottom was moving.

But that was no bottom.

It was a sea of sharks, just as we had hoped.

I'd never seen so many reef white tips in one place before.

What a treat!

This gave us a fantastic opportunity to see the sharks behaving naturally. They

seemed to completely ignore us. Their minds were on more important things,

dinner.

Now this is a different scene from what we saw with reef white tips.

Remember in the daytime how they were so classically placid, lying on the bottom

of the sand?

Well, this is the same animal.

This is classic.

reef white dip behavior at night.

Look at this. These things completely transform. It's almost like a different

animal all together. Now we understand why they're long and thin.

Because look at the way they feed. They rush in and out of these little nooks

and crannies of the reef, chasing fish in holes.

And they follow them in the holes and they can pull them out.

They're in feeding mode right now.

They're looking for food. Reef white -tip sharks generally aren't considered

dangerous or a threat to man.

As a matter of fact, most sharks aren't.

So they're pretty much going on about their business. As long as I don't do

anything stupid like grab one or spear a fish, I'll be perfectly fine.

Diving with reef white -tips is like playing on a rugby team. You become part

the pack, and it gets pretty rowdy.

Of course, normally it would be pitch dark down here, but we need light.

But the white tips don't. They can hunt by sensing the tiny electrical currents

produced in the muscles of fish.

If you're a fish, it's best to stay put when this wolf pack comes by.

They're excited.

They've had a couple of fish. They're going after more. So my guess is the

hunting time for these sharks is a little later at night.

And sure enough, We didn't have to wait long before the games began.

He's on his tail!

He's on his tail!

He's on his tail! Oh!

I think he's gone.

Oh, when less fish in the world.

They're definitely in hunting mode now.

We've seen about four Minpachi get taken already.

You almost think, oh, those fools!

Why are they coming out of the reef? If they only stayed buried, they would be

fine.

But how would you feel with 50 sharks chasing you?

myself in the reef here and it seems like I'm in an area where a couple of

might be hiding so I'll probably not stay here very long

What a start.

With the amazing reef white tips behind us, we can now focus on shark number

two.

Our next mission was to Wafer Bay.

Here, we hope to join the ranks of hammerheads, perhaps the strangest

shark we'll see here.

Hammerheads can grow to over four meters and weigh half a ton.

For a fearsome predator, they're hard to get close to. Seems the slightest noise

sends them away.

But I really wanted to see them up close and test one theory about why they come

here.

But it was an inauspicious start.

We were raring to go, but were caught in lousy weather, one of the mid -ocean

squalls common this far out to sea.

With all this equipment, it's pretty important to have a stable platform to

from, and big swells can be big trouble.

It's difficult to get decent weather forecasts out here, but the wind settled

down a bit and our enthusiasm to see the sharks got the better of us.

Diving deeper would help us get away from the swell, and in any case, below

meters, we were more likely to find the hammerheads.

But there were no sharks to be seen, and we were buffeted by strong currents.

The only thing we could do was elaborate

on what was wrecking our dive.

struggling against it right now.

But without the currents, there wouldn't be much life here.

It's the currents that are the key to this amazing variety and numbers of

animals that Coco supports.

Coordinating light, camera, and presenter is difficult at the best of

But under these squally conditions, it was proving to be nearly impossible.

It's a struggle down here, guys. I'm doing my best.

The two cable bashers, who were keeping my umbilical from snagging on the sharp

rocks, were actually keeping me alive. On this rig, my air comes down that

umbilical to the helmet.

Okay, guys.

We were thinking of calling it off, but just then we glimpsed sharks in the

distance, and it spurred us on to hang on a bit longer.

But once we got the cameras and lights in position and straightened out the

umbilical, well, you can imagine.

This is classic.

Talk about frustration.

I can see these hammerheads way out in the distance. They're lurking. And as a

matter of fact, I would bet that they would like to be right here where we

But they're not, because we are.

Here we've got about four support people.

We've got two cameras, lights, cables, these big umbilical cords. I'm blasting

all of this air.

We're making a lot of noise down here. And unfortunately, that's keeping away

the very thing we came here to film.

Highly unfortunate.

Incredibly frustrating.

But maybe, if we're patient, we'll still get lucky because they are here.

They're just hiding out.

Yeah,

there's nothing around.

We waited and waited, but they never came close.

For such big beasts, they sure seem shy.

Like most sharks, hammerheads are usually completely placid, and it's rare

them to attack.

Little did we know that our real danger would come from something else entirely.

Yeah. Oh, shit, the anchor line just broke.

Okay, I'm coming up with the anchor.

Coming up, guys. Go ahead and drift. Everything's cool.

But we have no anchor. We're coming up, okay?

Get that anchor line.

With all the gear we had in the water, this could truly be disastrous.

The anchor secures the whole operation, and without it, the boat will drag all

of us uncontrollably up and out to sea.

Are you cool? Are you guys going to be hitting rocks or anything?

Okay, we're coming up.

Everything's fine down here.

This changes everything.

safe diving mandate that you not only watch your depth, but come up slowly and

under control, neither of which we could easily do now.

Okay.

Here's a classic situation.

You notice, this is our anchor line, and it just parted down there. So our whole

operation, two boats, sound men, safety guys, people...

Everything just broke loose from the pinnacle.

And we're all drifting now, so we've got to be very, very careful.

We have no attachments to the land anymore. We're just drifting up there.

So we're all watching our gauges very carefully.

We're making a nice, slow ascent back to the...

I felt very relieved to be working with such professionals.

No one panicked, and we all arrived safely back to the surface.

So looking for the deeper sharks was no longer an option.

But I had an idea.

With all of this rain, the runoff might provide ideal conditions to encounter

the blacktip shark.

We needed an encounter today, and blacktips would provide a good one.

The black -tipped shark grows to over two meters.

It's powerful and will actually leap from the water, launching itself like a

missile through a school of fish like these.

We had to consider the tides, though. We rushed around the island, hoping to get

into the water before the tide was too low and the sharks disappeared.

Luckily, it didn't take us long to find the blackfin.

Sometimes they'll turn the shallows into a froth in their frenzied attack on

baitfish.

But visibility was poor, and the sharks were mighty active, so we decided to be

prudent and cut this dive short.

And just around the corner, the water is much clearer, so we headed there.

In Cocos, it pays to keep looking. You never know what you may find.

You know, one of the things you just can't help but notice is the

numbers of animals.

Not necessarily the number of different kinds, but in terms of sheer numbers,

it's hard to beat this place.

I mean, look at this.

else can you just go strolling along the bottom of the ocean and see thousands

of goat fish above them striped snappers out here in the blue water

well you can see behind me now school of jacks going by sometimes these

jacks number in the thousands and it's all because Cocos Island It's the tip of

a volcano that's come thrusting out of the sea about two million years ago.

Good, clean Pacific water moves along and it hits that island.

What it does, it pushes that cold, nutrient -rich water right up to the

A lot of nutrients, a lot of sunlight, a lot of plants. So phytoplankton blooms.

On the phytoplankton feeds zooplankton.

So plankton feeds little fish, which feed bigger fish, and more and more and

more of them, and pretty soon you're left with an unbelievable place.

And what I love about diving here is that you're constantly surprised.

Constantly.

We were just swimming back to the boat when I noticed a huge female marble ray

acting strangely.

I wasn't sure what was going on, so I decided to follow her. And then we

discovered what was happening.

Dozens of male marble rays, which are really just flattened sharks, were

congregating around a few of these large females.

Eventually, a female slows down and a male, well, they'll do what males do.

Every year, this breeding pack gets together around the island.

But to be in the water at exactly the same time as it was happening was

remarkable.

By now, we were exhausted and needed to surface.

But we seemed to have wandered into the adults -only section of Cocos.

I spotted another intimate aquatic ritual and felt we just couldn't pass it

What we're doing here is waiting for a very special activity.

These little fish behind me, the white ones, vertical black bars, are called

contact tags.

This time of day, as the sun is setting, fish... responding.

The convict tags gather together.

The females will rise up the bottom and go up and release eggs in the water

column. Then the males come rushing up behind them and squirt sperm in the

right next to the eggs. They drift off together. The eggs are fertilized.

They multiply, larvae, baby fish, boom, populate new reefs.

This is the group we want to watch.

Right there. There she goes.

Her stripes, or rather her bars, are thinner, and her body is not quite as

and shiny.

That's the female.

She's actually not even squishing the eggs out. And by zooming up into the

column, the release of pressure squishes the eggs out for her.

There. Oh, nope.

Nope.

It's going to happen, though. I know it's going to happen.

This is exactly the behavior we're looking for.

There we go. There we go.

You saw that big puff of smoke.

That's what we've been waiting for. You saw the female takeoff go right up about

20 feet off the bottom.

make a sharp bend and come right back down, pursued by about 15 males.

Up they went right after her, released their sperm.

Let's keep an eye on her because it will happen again.

Oh my gosh, that's funny. That's what we've been waiting for.

Beautiful creatures, aren't they?

For our next dive, we plan to go out into the deep water to find one of the

-time greats in the shark world.

Our fourth shark, the silver tip, is a magnificent shark, which you would

to find roaming a little way offshore.

It's powerful, can be three meters long, and it would be a real thrill to see

one of these up here.

We were heading out when we were given a golden tip by Nelson, the captain of

the ship.

He told us that silver tips come in close to shore at a special part of the

reef, which juts out toward deep water.

I would be delighted if this were true, because it would make it so much easier

to get close to the silver tips.

But I've never seen silver tips in the shallows, so I remained a little

skeptical.

If these large sharks were coming in so close to Cocos, there must be a really

good reason.

But what?

We're lucky. That's what we're going to see right now.

I thought this would be a wasted dive.

Surely, Nelson was confusing his sharks.

But as I was about to give up, there in front of me was a silver tip.

Unbelievable!

I followed it and ran into several more. Now I was really curious what they were

doing up here.

Here we are.

This is what we came for. Right now something amazing is taking place.

Right over there.

Sharks, I'm used to seeing in deep water, are up here at 40 feet for an

interesting reason.

Let's have a look.

Wow, look at this.

Good shark right there.

It's not the sort of shark that you normally see on the shallow reef in

Usually, they're reef sharks.

They call them that because they live on the reef. This one is a silver tip.

Silver tips are serious sharks. They're big. They eat other sharks as well as

big fish.

They go for the big stuff out in the deep water, the open water. I'm just not

used to seeing.

This shark here, I used to live in the Pacific. I lived in the Marshall

And we would always see these sharks deep on the drop -off, never in shallow

water like this.

Now, what on earth Silvertip is doing in these shallow waters is

beyond me.

Hopefully, if we stay long enough, we'll learn something about it.

What it's doing up here seems surprising.

However, if you look carefully, you'll understand. Look at the tail.

See those little fish? Those are rainbow wrasse.

Rainbow wrasse live on this rock right here. Now, this shark comes out from

deep water all the way over the flats. It's only 40 feet here to get cleaned.

These little wrasse come off the rock, leap up onto the shark, nip the little

parasites off.

tail off of the mouth the shark will actually slow down almost stop the rafts

into the mouth take all the little parasites off it's like ticks on the dog

don't like that

that

is one of the prettiest sharks i've ever seen in my life.

Look at that.

God, what a beautiful creature.

Sitting there.

She's almost gone.

I don't believe this. If you'd never see silver tips coming right over your head

like this, I have never, ever had this experience.

We didn't quite know how to find the next shark because they roam the open

between refueling stations like Cocos.

We'd have to go to the edge of the islands for any hope to meet them.

The silky shark is over three meters long and can be found in shoals of

hundred. Normally placid, they get a bit frenzied when they're feeding.

We knew large numbers of silky sharks congregated offshore, so our plan was to

venture out and hope that they would come to us. For this dive, I chose the

flexibility of a rebreather, which has wireless communications.

Convenient, but sorry, it's harder to understand me than in the helmet.

As we watched our turtle disappear off into the blue, familiar shapes began to

appear from the haze before us.

And almost as though a switch was thrown, their interest in us ceased.

And as suddenly as they appeared, they disappeared.

We followed.

And it didn't take long to see why they vanished.

A bait ball and a beauty.

Bait fish, like sardines and anchovies, normally feed on plankton. And at times,

they come right up to the surface. And that's when they're in big trouble.

They become obvious targets for predators like these big -eyed jacks.

creatures, the surface may as well be a brick wall.

They can't get out, and now with the predators around, they can't go down

either. In a futile defense, the little fish compact themselves tighter and

tighter into a ball.

The fish swim in frantic circles trying to escape as more and more of their

tormentors arrive for the feast.

It presents an unbelievable scene as Skipjack and Yellowfin Tuna crash into

bait ball at speeds of over 60 kilometers per hour.

The bait fish are utterly helpless in this situation.

And then... The sharks arrived.

Not only do the fish feed on such activity, masses of seabirds are also

attracted to the massacre.

On Cocos, there are over a hundred species of birds, including tern,

birds, and several species of boobies.

Cocos Island is full of seafarers' tales about pirate ships and strange

creatures from the deep. But one story was worth checking out. A very big deep

-water shark has been seen by divers on several occasions recently.

It's thought to be a type of sand tiger shark, a beast with snaggly teeth and

some seven meters long.

Of course, I wanted to meet it.

This is where our rebreather equipment would come into its own.

To go deep, you'd need to have time to decompress, come up slowly at the end of

your dive, and we'd need to be underwater for many hours.

This was potentially our most hazardous dive.

Because if anyone got hurt, for example with the bends, we would need a

decompression chamber and we'd need it fast.

And the nearest one was on the mainland over 450 kilometers away.

But this crew was experienced, and we were well prepared for the dive.

What a scene. Calm water, and below me, nothing but cobalt blue.

This is going to be great.

Again, the rebreather sound quality is not terrific, so bear with me.

Purging my rebreather. At depth, the normal air we breathe can be dangerous,

we swap our breathing gas.

Safer, but it also has a very odd side effect.

And that pretty much does it. So, I sound a bit like Donald Duck, probably,

that's because...

The wonderful thing for me about diving is that you can fly.

But as you go deeper, you start to feel the pressure. But not just physically.

Your mind starts racing.

And if anything goes wrong, you must think very clearly.

There's no quick way back to the surface.

There we are. We made it. This is at 252 feet.

And I can tell you this.

It's different down here.

Everything is cold and dark and steep.

Just then, I thought I saw a large shape

moving out in the gloom. I couldn't tell what it was, if anything.

At this depth, your mind plays tricks on you, but we decided to investigate.

Our seventh species in just one week is the deepwater sand tiger, and Cocos

offers a great chance.

because if it were not for the upwelling currents around the island, they would

remain in deeper water and out of reach.

Although I saw shadows everywhere, after a while, I began to feel I wasn't going

to meet him.

But in Cocos, there are always other payoffs.

Okay, this is Black Coral. Very precious stuff in the jewelry industry in

Hawaii. They harvest this stuff and make earrings, rings, all sorts of necklaces

out of it. It's a bit of a shame, but this is what it looks like in its

habitat. It's gorgeous stuff.

Even the latest technology has its limits.

As much as I wanted to find that shark, it wasn't going to be today.

We love diving down this far.

However, we've been down here pretty long.

So now it's time to start heading up.

After accepting the disappointment of not having seen the sand tiger shark,

deep dive was about to pay off in a big way.

During the long decompression ascent to the surface, we stopped to switch gases

and were shocked by what was just above our heads.

many sharks right here, day after day after day.

These are all hammerheads.

They're very social animals, and I have no clue what's really going on, so let's

don't even think about it.

It was

an opportunity

not to miss, but I wanted to put on my shallow water rig so you could

me better.

I just hoped to be there when I got back.

That head!

What on earth is that head all about?

Imagine an airplane with a wing.

A lot of experimental aircraft have little broad wings right in front of the

airplane. Now, when the airplane tilts, this really helps it go up and down and

up and down. The water is a very, very, very thick medium, much more dense than

air. So you broaden this head, flatten it out, give it a sharp leading edge.

All that hammerhead has to do is slightly tilt up or slightly tilt down,

becomes extremely... maneuverable. So, in tight spaces, it can turn on a dime,

it can go up and down. It really helps the maneuverability of a hammerhead to

have that hit.

Look at this hammerhead over here.

You see how it's rolled over on its side?

An angelfish. Those are king angelfish.

They've come up off from the reef and they're picking parasites off of it.

is a cleaning fish.

That's one reason that they show up here, to get clean.

You can see it's slowed down, rolls over on its side a little bit.

And the fish coming off the reef, cleaning it. You see it's barely moving.

That's a king angelfish on top of it. All of these little yellow fish are

actually butterfly fish called barberfish.

So there's two species, matter of fact, two families of fish.

that shark right now.

There must be, oh, I don't know, five or six butterfly fish cleaning them as we

speak.

Here comes a whole other group of butterfly fish.

So they'll just come in in circles like this.

moving too fast. You notice the fish didn't stop to clean that one. He just

passed right by.

They know when that shark wants to be

What a dive. What a place.

And what a finish.

It was great to finally see Hammerheads so close up.

During decompression, I took the time to look up at the tremendous views around

these volcanic spires and was mesmerized one final time by the pristine...

wonder of Cocos and its healthy abundance of life.

Diving around Cocos is utterly amazing.

It seems like there's more sharks per cubic meter of water here than anywhere

else in the world.

On nearly every dive, we found a different species and our goal of seven

in seven days was almost fulfilled.

We didn't find that elusive deep water sand tiger.

But that just gives me an excuse to come back.

And I will.