All language subtitles for Great.Blue.Wild.Series.1.04of11.Cozumel.1080p.HDTV.x264.AAC.MVGroup.org.eng

The island of Cozumel.

A dazzling haven for marine life

in the wild-blue waters
of the Caribbean Sea.

The visibility is
stunning.

The coral formations
are absolutely amazing.

It always takes my breath away.

Here is the world's
second-largest barrier reef,

a wild hunting ground
for perfect predators

at the top
of the oceanic food chain.

The bull sharks
are very, very big animals.

It reminds you just of your size
in the ocean.

Humble and
perfection
is the only thing you see.

It's perfection in the water.

A perilous journey,
deep inside hundreds of miles

of dark, mysterious
underwater caves,

where a single wrong turn

can mean the difference
between life and death.

We are far away from
an exit.

A minor problem
can cause a fatal accident.

A secret
world,
once considered sacred,

where only the bravest
dare to venture.

It's like
entering
another world.

(♪♪♪)

(♪♪♪)

(♪♪♪)

(♪♪♪)

(♪♪♪)

A lush and level island paradise

peering over the sapphire waters
of the Caribbean Sea,

Less than 20 miles
off the eastern coast

of Mexico's Yucatán Peninsula.

Situated on a bedrock
of limestone,

Cozumel is home to the largest
reef system in the Americas:

the Mesoamerican reef.

The reef
is an underwater wilderness:

providing a haven
for dazzling arrays of coral

and hundreds of species of fish:

from coral-crunching parrot fish

to the shy and elusive
splendid toadfish.

Sparkling visibility,

vivid turquoise waters,

and hundreds of miles

of dark and mysterious
underwater caves

have made Cozumel
a divers' dream.

Popularized by the legendary
oceanographer Jacques Cousteau

in the early 1960s,

the reef system
on the south side of the island

is now a national marine park.

Coral reefs cover less than
1 percent of the world's oceans.

And yet one quarter
of all marine creatures

live on a coral reef
at one time in their life.

In the warm, ultra-marine waters

that separate Cozumel
from the Yucatán Peninsula,

the white, sandy bottom
is stirred up

by the island's apex predator:
the bull shark.

Thick and powerful,

the bull shark cruises
warm, shallow waters.

This stretch of the Yucatán,

near the town
of Playa del Carmen,

has one of the largest
populations of bull sharks

in the Caribbean.

For three months each winter,
females, many of them pregnant,

make these warm, turquoise
waters their home,

before migrating to nearby
freshwaters to give birth.

You can normally see
them
in the distance circling around.

You get yourselves down
on the bottom, you kneel down,

and you wait for them
to come to you.

It's a very exciting experience

because you can see them
in the distance

and they get closer
and closer.

The bull sharks are very,
very big animals as well.

It reminds you of your size
in the ocean.

More than 10
feet long,

weighing as much
as a grizzly bear,

bull sharks move slowly
along the seabed.

Though they may appear
lethargic,

bulls are capable
of quick bursts of speed

to grab small and agile prey

with broad and triangular teeth

as heavily serrated
as a hacksaw.

Bull sharks
are relentless predators

perfectly honed over 400 million
years of evolution.

In the shark's snout are small,
electrical-sensing organs

called ampullae of Lorenzini

used to detect prey,

such as bony fish,
smaller sharks, and rays.

Slight electrical fields
radiated by animals swimming

are felt by the shark.

When an animal is in distress
and floundering,

it transmits a more powerful
electrical signal

that attracts the hungry shark.

Modified hair cells
embedded in the skin,

called neuromasts,
detect vibrations in the water

allowing the shark
to decipher the direction,

and speed of prey:

meaning the shark is able
to hunt in total darkness.

The bull shark
has a pulverizing bite force,

eight times more powerful
than a human's.

(♪♪♪)

Despite their terrible power
and fearsome appearance,

these bulls are docile
around humans.

(♪♪♪)

When you're
diving
with bull sharks,

it's nice to I guess
to get a sense of fear

but also, again, proper respect
for sharks

as you see them coming along.

And sitting there
watching them swim around,

it's amazing.

I love sharks.

Big sharks for me are everything

and so for me
to sit with bull sharks

and to have them swimming by
is inspiring.

It really is.

You feel the first
thing when
you see these animals is humble,

humble and perfection.

It's perfection in the water.

Commonly found
in shallow, coastal waters,

bull sharks also turn up
in unexpected places:

freshwater rivers.

Unlike most sharks

bulls are able to survive
for long periods

in both saltwater
and freshwater,

and have been found in both the
Amazon and Mississippi rivers.

Ancient creatures, sharks
have evolved in saltwater oceans

over hundreds
of millions of years,

and must retain salt internally
to survive.

For most sharks, a freshwater
habitat would be lethal.

Bull sharks, however,
have specially developed kidneys

that recycle the salt
within their bodies,

allowing them to thrive
in freshwater inlets.

Firmly planted at the top
of the oceanic food chain,

adult bull sharks
have no natural predators.

But because they frequent
coastal areas

and freshwater harbors,

they are at risk from pollution,

loss of habitat, and fishing:

caught accidentally
in long lines

or killed senselessly to meet
the demand for shark-fin soup.

(♪♪♪)

Apex predators
like the bull shark

are an essential part
of the ocean ecosystem.

Big eaters, they control
the population of other species.

A drastic decline
in the number of large sharks

can have a ripple effect:

allowing prey populations
to bloat,

and upsetting the delicate
balance of the oceanic food web.

(♪♪♪)

On this sandy ocean bottom,

the bull sharks
do not hunt alone.

(♪♪♪)

A southern stingray,
almost seven feet wide,

skims the seabed

in search of clams,
oyster and mussels,

exposed in the sand

by vigorous flaps
of its wide pectoral fins.

The stingray is perfectly
adapted for life on the seabed:

its flattened body tends

to match the shade
of the ocean floor,

camouflaging it from sharks
and larger rays.

(♪♪♪)

A venomous barb
near the base of the tail

is capable of inflicting
painful wounds on predators,

or on humans
who accidentally step on a ray

while it lies partially buried
in the soft sand bottom.

Waders are advised to perform
the 'stingray shuffle':

shuffling their feet,
rather than walking,

to alert the ray
of approaching danger,

and thereby avoiding

a potentially painful
stingray encounter.

Two spiny lobsters
hole up in a bed of coral,

antennae, longer than the rest
of their entire bodies,

are waved about
to fend off hungry predators

or simply unwanted attention.

(♪♪♪)

(♪♪♪)

Beyond the sandy shallows,

the reef at Paso del Cedral,

65 feet below the surface,

helps turn
a seemingly lifeless landscape

into a lavish garden.

Paso del Cedral
is one
of my favorite dive sites

on the island.

The reef itself
compared to other dive sites

is a smaller reef

but it means that it's
absolutely packed with life.

My personal
favorite
of the reefs

would be Paso del Cedral.

It has life like nothing else.

You're not getting
the big coral structures

like you are further south

but there is so much life
on Paso del Cedral.

Reefs like Paso del
Cedral
embrace about one-quarter

of all marine species
on the planet.

Ocean currents collide
with the reef,

carrying up from the depths
nutrients

that attract a rich bounty
of aquatic creatures.

A hawksbill sea turtle,

its shell streamlined
to aid in swimming,

soars through the open ocean.

(♪♪♪)

(♪♪♪)

Out in the
distance
you see a rock

that looks like
it's surrounded by angelfish.

You swim a little bit closer

and you realize that rock is,
in fact, a turtle feeding

and the turtle doesn't even care
that you're there.

You get close to him,
you can hang out with him

and watch him feed.

Hawksbill turtles are
primarily found on coral reefs,

rich with their favorite food:
sea sponges.

(♪♪♪)

A narrow head
and hawk-like beak

are ideal for tearing sponges
from crevices in the coral,

then crushing them
with powerful, toothless jaws.

Some sponges are highly toxic,

even lethal to other creatures.

The turtle is able
to absorb these dangerous toxins

in its body fat,

without experiencing
ill effects.

Hawksbills are omnivores,

and will also feed
on marine algae,

sea urchins and jellyfish.

The turtle's hard shell,
and armored head,

protect it from the stinging
cells of the jellyfish.

(♪♪♪)

Though they spend
most of their lives underwater,

sea turtles
are air-breathing reptiles,

and must surface
to take in oxygen.

(♪♪♪)

A resting sea turtle might
remain submerged for hours.

A turtle that uses up energy
to dive for food

or escape from predators
must breathe more frequently.

(♪♪♪)

(♪♪♪)

Like all turtles,

the hawksbill has a wide,
armored shell

that safeguards
its vital organs.

The hard casing defends
the turtle from predators:

such as sharks and crocodiles,

but the same shell
that protects the hawksbill

has nearly led
to its extinction.

Beautifully colored,

with large, scale-like
structures known as scutes,

its shell is highly valued:
used to make jewelry,

and other ornaments,
sold as 'tortoiseshell'.

Despite its status
as an endangered species,

hawksbill eggs
remain a delicacy,

and adult turtles are killed
for their meat and shells,

or caught accidentally
in long fishing lines.

(♪♪♪)

Strong paddle-shaped
front flippers

propel the turtle
through the open ocean.

Hawksbills are the descendants
of reptiles

that travelled the ocean more
than 100 million years ago.

Graceful, ancient,

they are an irreplaceable link
to our prehistoric past.

(♪♪♪)

Sea turtles have an average
lifespan of about 80 years.

But they are infants

compared to the oldest animal
in these waters:

the coral reefs.

Coral is a living organism,

and most established
coral reefs

are between 5 and 10,000
years old.

Yet around the world,

these ancient creatures
are under threat:

from pollution, destructive
fishing practices,

and the effects
of climate change.

High water temperatures
cause algae

to leave the coral tissue,

depriving the coral
of its major food source,

and leaving the reef
susceptible to disease.

The reef at Paso del Cedral
supports such an abundance

of marine life
that it demands a closer look,

for one of the ocean's most shy
and secretive creatures.

The cool
thing
with Paso del Cedral

is you can find
the splendid toadfish, okay?

The splendid toadfish,
we only have it here in Cozumel

so it's something very special.

You can find them hiding out
in little holes.

They're very, very shy.

As a species,
toadfish are
far from powerful swimmers,

and traveling great distances
is not easy.

As a result,
populations of toadfish

can become
geographically isolated,

potentially giving rise
to endemic species.

To spot a toadfish

divers must look
for the telltale signs:

lines in the sand made
by the fish's beard.

Like many bottom-dwelling fish,

the toadfish has eyes
at the top of its head,

to spot prey swimming above.

(♪♪♪)

Most life in these warm,
tropical waters

is concentrated on the reef.

French angelfish,

swim on their side
to reduce their surface area

and make it easier
to move through the current.

French angels are a rare breed
of ocean fish.

Whereas most fish that mate
go their separate ways,

these French angels
tend to stick together

feeding on the reef as a duo,

and even helping each other

defend their territory
against other fish.

A pair of grey angelfish
forages on the reef.

Like all angels, greys feed
primarily on sponges,

tearing them from the reef
with small, powerful mouths.

Overlapping rows of teeth

cut through the hard exterior
of the sponge.

A thick layer of mucous,
secreted by the angelfish,

then coats the meal
protecting the fish's stomach

from needle-like spines
in the sponge

designed to deter predators.

(♪♪♪)

Further down the reef

one of the ocean's
most-striking creatures:

an electric-blue
queen angelfish.

Though remarkably bright
and colorful,

queen angels
are able to blend in

with the reef's technicolor
maze of coral.

Swimming under a darkened arch
in the reef,

the queen angelfish emits
a brilliant iridescent glow.

Rich in nutrients
the reef at Cozumel

has transformed these shallow
waters into a giant aquarium.

Sticking close to the coral

a sponge-eating rock beauty
lives up to its name.

(♪♪♪)

Small fins

make the white-spotted filefish
a slow swimmer.

And it avoids the open ocean,
hugging the reef,

on the lookout
for algae and sponges.

(♪♪♪)

When threatened,

the scrawled filefish
wedges itself into crevices,

erecting spines
on its head and belly

to lock itself into place.

(♪♪♪)

A honeycomb cowfish:

its body encased
in hard external armor

that protects it from predators.

Openings in the shell,
around the gills,

allow for respiration.

Strong, rounded rear fins
help cowfish move swiftly,

as they patrol the reef
for marine invertebrates.

Finding food on the reef
is not easy.

The hogfish uses
its elongated pig-like snout

to root around the seabed,
looking for small crustaceans,

which it crushes
with its powerful jaws.

Seeking an entirely different
kind of prey

is one of the most remarkable
creatures on the reef:

the parrotfish.

Its colors, patterns,

and even its gender
can change repeatedly.

Sex changes occur
when populations are low,

and either more breeding males,
or more breeding females,

are needed.

The parrotfish secretes
a cocoon of clear mucous,

to protect it from parasites,
like bloodsucking isopods,

while it sleeps.

Isopods, known as
'the mosquitoes of the sea',

are dangerous predators:

sucking the blood from fish
as they sleep.

But perhaps the most
exceptional characteristic

of the parrotfish
is its diet.

Parrotfish feed primarily
on the coral and algae

that grow on the surface
of the reef.

Hard, beak-like teeth
tear into the reef,

biting off not just the coral
but its hard skeleton as well.

Powerful, grinding teeth
in the throat crush the coral,

freeing the algae-filled polyps
that nourish the parrotfish.

The pulverized hard-coral
skeletal material

ingested by the fish passes
through its digestive system

and is deposited back
into the ocean

in clouds
of fine white coral sand.

One parrotfish can produce
200 pounds of sand

in a single year.

So whenever
you see
a parrotfish

going by and leaving its trail
behind it,

that is the sand that will, in
the end, wash up on the beach.

This is part of the process

that the parrotfish gives
to the reef in Cozumel.

The Yucatán
rainforest.

Part of the largest continuous
expanse of tropical rainforest

in Central America.

Beneath this jungle floor

lies one of the planet's last
great wilderness frontiers.

A secret subterranean world...

explored
by only the bravest divers.

The cenotes.

(♪♪♪)

To dive in the
cenotes,

you enter

in a freshwater
overhead environment.

It's very serene,
it's very peaceful.

You're close to the jungle
so you're very close to nature.

The jungle sits
atop
a thick bed of limestone,

once part
of an ancient undersea reef.

Over millions of years,

rainwater, made acidic
by carbon dioxide in the soil,

percolates down into the earth
eating away at the limestone

and creating massive
underground cave systems

flooded by pools of groundwater.

Stretching for hundreds
of miles,

the world's longest underground
water systems

are found
in these subterranean chambers.

(♪♪♪)

Once you get
inside the overhead environment,

you're surrounded by darkness.

You have your lamp,
you have your guide

and you become at peace
with yourself.

You become very relaxed

and it's a very slow,
very peaceful dive.

Yet few have
witnessed
the farthest reaches

of the Yucatán's
underwater galleries.

Explorers who squeeze
into these tight spaces

and maze-like passageways

take their lives
into their own hands.

(♪♪♪)

Cave-diving is
considered

one of the most dangerous part
of diving.

We are far away from an exit.

You need to be prepared
with double tanks,

double regulators,
technical diving equipment.

A small fail in equipment
or in logistics

can lead you easily
to a fatal accident.

An
underwater sign
warns of the dangers.

Hundreds of divers
around the world

have perished in caves
like these.

In the darkened depths,

with the nearest exit
hundreds of feet away,

it is easy
to become disoriented.

In the submerged caves
of the Yucatán,

becoming lost underwater,

with a limited supply
of oxygen, can be fatal.

To keep from getting lost,

cave divers unspool distance
lines to mark their route.

Line markers point the way
to the exit, and safety.

Daring divers were not the first

to explore
these underwater cathedrals:

white catfish thrive
in this lost, dark world.

(♪♪♪)

They are night-time feeders,

scouring the caverns for
bottom-dwelling invertebrates.

In the darkness of the caves

monumental formations hang
like icicles from the ceiling.

Stalactites.

Millions of stalactites.

Dissolved limestone
in the water

escapes into the air
and hardens as calcite.

Over time, minuscule amounts
of calcite

build up and drip
from the cave ceiling.

Air currents
and the flow of water

help determine the shape
of these wild sculptures,

which can range in size
from mere inches

to the height
of a two-story house.

Yet each begins
with a single drip.

Mineral-rich water that seeps
through the cave ceiling

or drips off the end
of stalactites

creates stalagmites,

which emerge like traffic cones
from the cavern floor.

It's hard to believe
that
something so close to the shore

or something
in the middle of nowhere

can be so amazing
under the water.

Some of them have air pockets
that you come up in

and you're in this middle
of this cave

in the middle
of kind of nowhere.

It's different than anything
else that you have here.

It's not the same
kind of diving.

In the
rainforest
of the Yucatán Peninsula,

there are no rivers
and no streams.

Cenotes,

the flooded openings
to these underwater caves,

were once the only source
of freshwater

for one of the world's great
early civilizations:

the Maya.

The word 'cenote'
means 'sacred well'.

The Maya constructed villages

around these flooded shafts,

which they believed
were a gateway to the gods.

(♪♪♪)

On Cozumel's rich
and colorful reef,

there is a daily battle
for survival.

An abundance of prey
makes these waters

a rich hunting ground
for hungry predators.

Predators,
like the spotted eagle ray.

Ten feet wide,

weighing as much
as a grand piano,

eagles are the giants
of Cozumel.

Propelled by powerful flaps
of its wing-like pectoral fins,

the eagle ray soars
through the open ocean.

A long whip-like tail,

equipped with two
to six venomous barbs,

defends the ray
against predators.

Its speed and size keep it safe

from even the largest shark

that prowls these waters:

(♪♪♪)

The nurse shark.

(♪♪♪)

In these areas
you've
got a really good chance

to come across the nurse sharks.

They like to hang out
under the ledges

where there's a sandy bottom
so they can lie down

and hide out
of the current there.

Primarily nocturnal
animals,

nurse sharks spend their days
resting

and conserving precious energy.

Unlike other requiem sharks,
which must swim constantly

to force oxygenated water
over their gills,

nurse sharks are able to breathe
while stationary:

using muscles around
their mouths to pull in water

that then flows
over their gills.

(♪♪♪)

Too slow for the daytime chase,

nurses prefer to hunt at night:

suctioning up
resting prey species

through their vacuum-like
windpipes.

Though sluggish swimmers

nurse sharks
are imposing predators:

reaching lengths of ten feet,

and weights
of more than 300 pounds,

the average body mass
of an NFL lineman.

(♪♪♪)

Powerful jaws crush the hard
shells of crustaceans

which are devoured by suction

and thousands of sharp,
ragged teeth.

As this pair of nurse sharks
slowly patrol the reef,

they are joined
by more fearsome hunters:

barracudas.

Built like a hunting knife,
and just as dangerous,

the barracuda
is a master predator.

Small, razor-sharp teeth,

backed by a larger set
of dagger-like fangs,

shred fish into small pieces
for easy digestion.

Long and lean, barracudas
are frighteningly quick:

capable of cutting
through the water

at speeds of up to
25 miles an hour,

in pursuit of prey.

The ability to inflate
and deflate its swim bladder

means the barracuda
is able to squeeze

into small crevices
in the coral,

to track down
small reef fish.

When hunting
near the reef bottom,

barracudas are able
to change color,

to blend in
with their surroundings

and surprise unwary prey.

(♪♪♪)

With so many barracudas
on the prowl,

these schoolmaster snapper

would be wise
to not drop their guard.

As the name suggests,

schoolmasters swim
in classroom-size shoals

scouring the reef
for crustaceans,

such as this hermit crab,

hunkered down inside the empty
shell of a marine snail.

(♪♪♪)

Survival on the reef
is a struggle,

and camouflage
can be a lifesaver.

Rather than hiding in the sand
like the hermit,

the coral crab blends in
with its surroundings,

managing to match
both the color,

and texture, of the coral.

(♪♪♪)

Farther along the reef

is an even craftier master
of disguise:

the Caribbean reef octopus.

One of the few creatures
on earth

able to alter its appearance
in a flash.

Thousands of color-changing
cells beneath the skin

form patterns, colors
and shapes

on the surface of the skin

that match the surrounding rocks
and coral.

You see them changing
colors,

you see them moving around
and hunting.

They are extremely good
at camouflage.

Once you find them,
they stop moving,

they fan themselves out

and they change their colors
instantly

and it's an amazing thing
to see.

(♪♪♪)

During
the day,

the octopus hides out in
coral overhangs on the reef.

At night, it comes out to hunt,

using a technique
called 'tenting':

spreading its webbed arms
into a wide canopy

used to net prey.

It is an extraordinary sight.

But here on the seabed

there are more unusual creatures
to behold.

The frogfish.

Equally adept at camouflage,

lies in wait for passing prey.

They are
excellent
at camouflaging themselves

and they do not move at all.

So you can be staring at one

and you can hardly realize
it's there.

A skilled
hunter,

the frogfish wiggles
its rod-like dorsal spine

to lure prey,

which is then attacked
with blinding efficiency.

It may be small,

but the frogfish
can expand its mouth

to twelve times its normal size,

to catch prey large prey
with long needle-like teeth.

The sea cucumber has the most
remarkable defense mechanism:

they actually mutilate
their own bodies.

When threatened,

the sea cucumber
will contract its muscles

to expel some of it internal
organs through its anus.

An action that confuses
and deters predators.

The missing body parts
are regenerated.

Like all members of the species,

this sea cucumber breathes

by drawing oxygenated water
in through the anus

and then expelling it.

A bearded fireworm
feasts on the coral.

Stretching 2 to 4 inches,

it is one of the smaller
creatures on the reef.

But divers must be wary:

the fireworm's bristles
can penetrate the skin,

injecting a powerful venom.

The results can be painful,

and often lead to dizziness
and nausea.

Even smaller than the fireworm,

a pipehorse,
no larger than a human thumb,

grips the coral
with its monkey-like tail.

Seahorses
are not strong swimmers,

and can easily be carried away
with the current.

Amid a blizzard of marine snow:

decaying organic matter
falling from the waters above.

(♪♪♪)

From spectacular
coral formations,

and secret subterranean worlds,

to powerful apex predators,

and magnificent, soaring giants,

the shallow seas
of the Yucatán Peninsula

are home to a world
among the reefs.

And one of the many wonders
of the great blue wild.

In a week
you can have cave diving,

shark diving,
reef diving.

All in the same place.

Normally people travel
all around the world

to dive different places

but here, you can do
different kind of diving

in the same place.

For me in the
Caribbean,
Cozumel is my favorite diving.

You've got thousands of years
of history

with the stalagmites
and the stalactites.

The Mayans believed that it was
the entrance to the underworld.

So it gives you an idea.

It's a little bit eerie,
but it's stunning to see.

It's like entering
another world.

(♪♪♪)

I've been to various
different destinations

but there's always something
about coming back to Cozumel

and getting in the water here.

It always takes my breath away.

(♪♪♪)

(♪♪♪)

(♪♪♪)

(♪♪♪)