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 miles 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 you 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 life.
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 sharks.
The reason so many sharks come here is because Cocos is like a truck stop in the 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 excited to come back.
I first came to Cocos Island 12 years ago.
Even then, I recognised that this place was special
But I hadn't realised just how special.
I knew there were a lot of species of sharks in Cocos
but I'd 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 whitetips,
the bold and beautiful silvertip.
And, of course, the mighty hammerhead.
There's also that great mystery about a deep-water 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.
You can see Mark dealing with his scrubber over there right now.
But basically, these rebreathers allow us extended bottom times
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 here, breathing air.
It all comes down through this big umbilical cord.
So we have two-way communication plus the cameraman can hear me.
So this bit of technology allows 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 whitetip.
Reef whitetip 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 wonder why I'm appearing so irresponsible in walking 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 whitetip sharks are found right on the sandy sea floor.
I wanted to get a nice cosy 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?
Cocos Island supports an enormous population of reef whitetip sharks
and you can see their daytime behaviour is rather lazy.
If they're not slowly swimming like these above,
they're laying on the bottom, taking a rest.
Generally, in little sandy patches and reef areas like this.
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 whitetips exhibit this kind of behaviour in the daytime.
They don't do much. They just kind of slowly move around,
swim in small circles 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 whitetips, you see his mouth pumping,
that's a trick that they can do that most sharks cannot.
They physically pump water over the gills
so they can get oxygen exchanged while at rest.
Now, speaking of rest,
that's what's going on here.
Reef whitetip sharks are like Dr Jekyll and Mr Hyde.
In the daytime, they're laying around, swimming in slow circles,
not doing much at all.
Believe me, this guy lives on the night shift.
Later on, we'll see this animal performing a very, very different behaviour.
It might seem a little 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 Nino came to town.
Warm water has moved into Cocos Island
and basically killed all of this coral.
Unfortunately, this once-thriving coral reef is now rendered...
algae-covered rubble.
Another problem they have is this.
This is a crown-of-thorns starfish.
Occasionally, these crown-of-thorns starfish have a population explosion.
When that happens, these things are everywhere.
And guess what they eat.
You got it. Coral.
So what this one is doing, it's clinging on
to this little mini coral head right here, which is called porites.
It exudes its gut. It takes its gut out of its body, covers the coral, digests it,
and then brings the gut back in and crawls away
after a day or so,
leaving nothing behind but a bleached-out, white, dead skeleton.
Many years ago, these crowns-of-thorns were thought to be the bane of the reefs.
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.
So... best to just leave it alone and that's what we're gonna 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.
Garden eels are so called because 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.
Poof!
Away they go.
Down in the hole.
Safe as they can be.
Beautiful creatures, aren't they?
And right on cue, a blacktip 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 whitetip sharks around Cocos
cos 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.
But thankfully, Cocos is now a well-protected marine nature reserve
with a 12-mile 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 fund.
In order to film the Jekyll and Hyde nature of whitetips,
we would have to back 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 come in their hundreds.
Whitetip sharks are not scary in themselves
but at night, they frantically 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'd hoped.
I'd never seen so many reef whitetips 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, like dinner.
Now, this is a different scene from what we saw with reef whitetips.
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 whitetip behaviour at night.
Look. They are completely transformed. It's almost like a different animal.
Now we understand why they're long and thin, because look at the way they feed.
They rush in and out of those little nooks and crannies of the reef,
chasing fish in holes and they follow them in the hope they can pull them out.
Classic.
They're in feeding mode right now. They're looking for food.
Reef whitetip sharks generally aren't considered dangerous to man.
As a matter of fact, most sharks aren't.
So they're pretty much going about their business
and as long as I don't do anything stupid, like grab one or spear a fish,
I'll be perfectly fine.
Diving with reef whitetips is like playing on a rugby team.
You become part of the pack and it gets pretty rowdy.
Of course, normally it would be pitch-dark down here but we need light.
The whitetips 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 real 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! One less fish in the world.
They're definitely in hunting mode now.
We've seen about four mempachi get taken already.
You almost think, "Oh, those fools! Why are they coming out of the reef?
"If they only stayed there, they'd be fine."
But how would you feel with 50 sharks chasing you?
I've kind of wedged myself to the reef here
and it seems like I'm in area where a couple of fish might be hiding.
So... I'll probably not stay here very long.
(Chuckles)
Ah.
Hello, boys.
That was great. That was great.
What a start. With the amazing reef whitetips behind us,
we can now focus on shark number two.
Our next mission was to Wafer Bay.
Here we hoped to join the ranks of hammerheads.
Perhaps the strangest-looking shark we'll see here.
Hammerheads can grow to over four metres and weigh half a ton.
For a fearsome predator, they're hard to get close to.
It 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 important to have a stable platform to dive from
and big swells can be big trouble.
But still, if it's rough, then it's not going to work for us.
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.
In any case, below 30 metres, we were more likely to find the hammerheads.
But there were no sharks to be seen and we were buffeted by strong currents.
Erm... I don't know what else we can do here.
There's nothing but blue water and a few fish around.
The only thing we could do was elaborate on what was wrecking our dive.
Rolls down.
One of the things that makes Cocos Island such a rich place is its currents.
You can see that I'm having a heck of a time 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 Cocos supports.
(Groans)
Coordinating lights, camera and presenter is difficult at the best of times
but under these squally conditions, it was proving to be nearly impossible.
It's a struggle down here. I'm doing my best.
The two cable bashers who were keeping my umbilical from snagging on the rocks
were actually keeping me alive.
On this rig, my air comes down that umbilical to the helmet.
OK, 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.
As a matter of fact, I would bet that they would like to be right here where we are
but they're not because we are.
Here we've got about four supporting 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. Uh! Incredibly frustrating.
But maybe, if we're patient, we'll still get lucky because they are here.
They're just hiding out in the shadows.
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 for 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.
OK, 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. OK?
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 or are you guys going to be hitting rocks or anything?
OK, we're coming up. Everything's fine down here.
This changes everything.
Safe diving mandates that you not only watch your depth
but you come up slowly and under control.
Neither of which we could easily do now.
OK.
Here's a classic situation.
If you notice, this is our anchor line and it just parted down there.
So our whole operation - two boats, sound men, safety guys,
people giving me air, 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 attachment to the land any more.
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 boat.
Everything's fine but this kind of stuff can happen in a tricky operation.
You can pull up a little bit of umbilical.
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 run-off might provide ideal conditions
to encounter the blacktip shark.
We needed an encounter today and blacktips would provide a good one.
The blacktip shark grows to over two metres.
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 blacktips.
Sometimes they'll turn the shallows into a froth in their frenzied attack on bait fish.
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.
On 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 extraordinary number of animals.
Not necessarily the number of different kinds
but in terms of sheer numbers, it's hard to beat this place. Look at this.
Where else can you just go strolling along the bottom of the ocean
and see thousands of goatfish?
Above them, striped snappers.
Out here in the blue water, you can see behind me now
a school of jacks going by.
Sometimes these jacks number in the thousands.
It is all because Cocos Island is the tip of a volcano
that's come thrusting out of the sea about two million years ago.
The good clean Pacific water moves along and it hits that island.
When it does, it pushes that cold nutrient-rich water up to the surface.
A lot of nutrients, a lot of sunlight, a lot of plants.
So phytoplankton blooms. On the phytoplankton feeds zooplankton.
Zooplankton feeds little fish which feed bigger fish
and more and more and more of them.
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, he'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 up.
What we're doing here is waiting for a very special activity.
These little fish, the white ones, vertical black bars, are called convict tangs.
This time of day, as the sun is setting, fish are spawning.
The convict tangs gather together and the females rise off the bottom
and go up and release eggs in the water column and then the males come rushing up behind them
and squirt sperm in the water right next to the eggs
and they drift off together and the eggs are fertilised.
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 white and shiny.
That's the female.
She's actually not even squishing the eggs out.
And by zooming up into the water column,
the release of pressure squishes the eggs out for her.
There! Oh, no, no.
It's going to happen, though. I know it's going to happen.
This is exactly the behaviour 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 take-off 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 and released their sperm.
Let's keep an eye on her because it will happen again.
Oh, my God. That's spawning. That's what we've been waiting for.
Beautiful creatures, aren't they?
For our next dive we plan to go out into the deeper water
to find one of the all-time greats in the shark world.
Our fourth shark, the silvertip, is a magnificent shark,
which you would expect to find roaming a little way offshore.
It's powerful, can be three metres long
and it would be a real thrill to see one of these up close.
We were heading out when we were given a golden tip
by Nelson, the captain of the ship.
He told us that silvertips 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 silvertips.
But I've never seen silvertips in the shallows, so I remained a little sceptical.
If these large sharks were coming in so close to Cocos,
there must be a really good reason-but what?
If 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 silvertip.
Unbelievable.
I followed it and ran into several more.
Now I was really curious what they were doing here.
Here we are. This is what we came for.
Right now something amazing is taking place right over there.
Sharks that I've been used to seeing in deep water are here in 40 feet.
An interesting reef, let's have a look.
Wow. Look at that.
A ten-foot shark right there.
Not the sort of shark that you normally see on the shallow reef in Cocos.
Usually, they're reef sharks. They call them that because they live on a reef.
This one, it's a silvertip.
Silvertips 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 Islands.
And we would always see these sharks deep in the drop off,
never in shallow water like this.
Now, what on earth a silvertip is doing in these shallow waters is beyond me.
Hopefully if we stay long enough, we'll learn something about him.
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 wrasses.
Rainbow wrasses live on this rock right here.
Now, this shark comes out from very deep water all the way over the flats -
it's only 40 feet here-to get cleaned.
These little wrasses come off the rock, leap up on to the shark
and nip the little parasites off the tail, off of the mouth.
The shark will actually slow down, almost stop,
and the wrasses go into the mouth, take all the little parasites off.
It's like ticks on a dog. They don't like that.
(Chuckles)
Boom-boom-boom-boom-boom.
That is one of the prettiest sharks I have ever seen in my life.
Look at that.
What a beautiful creature.
Sitting there.
She's almost stalling.
They are giving us a show.
I don't believe it. You never see silvertips coming over your head like this.
I have never ever had this experience.
- Hello, boys. - You got water in there.
Yeah.
We didn't quite know how to find the next shark
because they roam the open seas between refuelling 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 metres long
and can be found in shoals of several 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 if it's harder to understand me than in the helmet.
Aw. Here we go. A green sea turtle.
You can tell it's a green sea turtle. It has a very smooth edge to its shell.
Sometimes you can make friends with them. Let's see if this guy's friendly.
Hello, fella. Hello.
They are vegetarians, although they will eat, of all things, jellyfish
out in the open sea.
Beautiful creatures.
Good luck, little guy.
See you later.
As we watched our turtle disappear off into the blue,
familiar shapes began to appear from the haze before us.
And, almost as if 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 bar and a beauty.
Bait fish, like sardines and anchovies, normally feed on plankton
and, at times, they come to the surface and that's when they're in big trouble.
They become obvious targets for predators like these big-eyed jacks.
For water 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.
In a futile defence, 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 yellow fin tuna
crash into the bait ball at speeds of over 60 kilometres per hour.
The bait fish are utterly helpless in the situation.
And then the sharks arrive.
Not only do the fish feed on such activity,
masses of seabirds are also attracted to the massacre.
On Cocos, there are over 100 species of bird,
including terns, frigate 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 deepwater shark has been seen by divers on several occasions recently.
It's thought to be a type of sandtiger shark,
a beast with snaggly teeth and some seven metres long.
Of course I wanted to meet him.
This is where our rebreather equipment would come into its own.
To go deep, you 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.
Cos 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 kilometres away.
But this crew is experienced and we were well prepared for the dive.
Yeah, got you loud and clear.
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.
(Crackling) I didn't see a valve over there.
OK, the purpose of this dive is to go deep.
We're going to be going down to about 250 feet.
There's one important safety factor and that's Mark Thurlow.
Mark will be diving with me, sharing the extra bottles and gases
and ways to save me if I have a problem, or if he has a problem, save himself
or save our cameramen.
Next thing is fun. Take a breath and blow it out.
I'm purging my rebreather. At depth the normal air we breathe can be dangerous,
so we swap our breathing gases.
Safer but it also has a very odd side effect.
(High-pitched) And that pretty much does it. (Chuckles)
I sound like Donald Duck probably but that's because I've replaced some of my air with helium.
So I don't have any nitrogen in my system right now.
So Mark, if you're ready, I am too, so let's hit it.
We'll see you at 250 feet.
The wonderful thing for me about diving is that you can fly.
But as you go deeper, you start to feel the pressure.
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.
Here we are. We made it. This is 252 feet.
And I can tell you this, it's different down here.
Everything is cold and dark and it seems a lot quieter.
Just then I thought I saw a large shape moving out in the gloom.
I couldn't tell what 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 sandtiger
and Cocos offers a great chance,
because if it were not for the 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.
OK, this is black coral, very precious stuff in the jewellery 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 natural 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.
You 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 sandtiger shark,
the 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 above our heads.
Look at those things. Wow!
I just can't help but wonder, what on earth are they doing?
Why are there so many sharks right here day after day after day?
These are our 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 and just watch.
You know, I've spent a lot of time with hammerheads in a lot of different places.
(Chuckles) But I don't remember seeing them like this anywhere.
This is great.
It was an opportunity not to miss
but I wanted to put on my shallow-water rig so you could understand me better.
I just hoped they'd be there when I got back.
That head... What on earth is that head all about?
Imagine an airplane with a wing.
As a matter of fact, a lot of experimental aircraft have a little broad wing
right in front of the airplane.
Now, when the airplane tilts,
this really helps it go up and down and up and down
and water is a very, very thick medium, much more dense than air.
So you broaden this head,
flatten it out and give it a sharp leading edge,
all that hammerhead has to do is slightly tilt up or slightly tilt down
and it becomes extremely manoeuvrable.
So in tight spaces, it can turn, it can go up and down.
It really helps the manoeuvrability of a hammerhead to have that head.
Look at this hammerhead over here.
You see how it's rolled over on its side?
And angelfish, those are king angelfish.
They've come up off of the reef and they're picking parasites off of it.
This is a cleaning station.
Perhaps that's one reason that they show up here, to get cleaned.
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 can see it's barely moving. That's a king angelfish on top of it.
All these little yellow fish are butterfly fish called barber fish.
So there's two species, as a matter of fact, two families of fish,
cleaning that shark right now.
There must be, I don't know, five or six butterfly fish cleaning him as we speak.
Here comes a whole other group of butterfly fish.
So they just come in in circles like this,
spin around a little bit, get clean for a while
and then wander off and join the pack,
come back around again and throughout the day, this will happen time and time and time again.
Here's another one here.
This one's moving too fast.
They know when that shark wants to be cleaned, because they'll slow down and almost stall.
Phew. 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 mesmerised 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 metre of water here
than anywhere else in the world.
On nearly every dive, we found a different species and our goal
of seven kinds in seven days was almost fulfilled.
We didn't find that elusive deepwater sandtiger
but that just gives me an excuse to come back...
and I will.