All language subtitles for Wonders of the Celtic Deep S01E03 1080p BluRay x264-TABULARiA_track3_[eng]

SIAN PHILLIPS (VO):
It's early summer

and 20 miles off the coast
of Pembrokeshire...

the warming seas of the Celtic Deep
are starting to stir...

drawing in long distance travellers.

A fin whale.

One of the biggest animals on the planet.

She's here for a summer of feeding.

She could well have travelled
over 6,000 miles to get here.

After centuries of whaling, fin whales
have been on the brink of extinction.

But it's believed
that numbers are now on the rise.

And these ocean giants are returning
to the seas around Wales.

She's not the only one
coming to these rich waters

for what they hope will be a time of plenty.

Wales is a coastal nation.

The sea /s in our soul.

Full of hidden treasures...

wonders...

and giants.

A sea of mythical coasts...

with extraordinary creatures...

secretive shallows...

...and hidden depths.

These are the Wonders of the Celtic Deep.

St Anne's Head,
the westerly edge of Pembrokeshire.

Reaching out into the St George's Channel,
here the Celtic and Irish Sea meet.

Now we /eave /and...

and travel out into the Celtic Deep.

Eight miles offshore stands Grassholm.

BIRDS CAW

Of Wales's 52 islands, it's the most remote.

Making it a perfect breeding ground
for the North Atlantic's largest seabird.

The gannet.

With his six-foot wingspan
he's well suited to a life out at sea.

He greets his life partner with a knocking
of bills to renew their bond.

BIRDS CAW

Ten percent of the world's population
of Gannets come here every spring.

Some 40,000 birds crammed
onto this tiny island.

Together this pair will raise a single chick.

To keep it fed, they will take it in turns
to go far out to sea in search of fish.

BIRDS CAW

A further 12 miles out...

lies the Smalls Lighthouse.

Sitting on the last rocky outcrop
Wales has to offer

before losing the fight with the sea.

SEALS BELLOW

It's also the final haul-out
of the Atlantic grey seal.

SEALS MOAN

Giving them a resting place from fishing
in the open ocean.

From here, the sea floor gives way
to the open ocean beyond.

This is the domain of Dylan ail Don

God of the Celtic Deep.

And the territory of the common dolphin.

All who venture here are prime targets
for investigation.

These sociable
and highly intelligent cetaceans

are one of the few animals
to play into adulthood.

The dolphins are drawn
to passing boat traffic...

taking it in turns to ride the bow wave.

Game over.

DOLPHINS WHISTLE

Living in pods of up to 50 individuals...

common dolphins have complex social lives.

Which can get even more tangled
when families gather to form superpods.

DOLPHINS WHISTLE

It's thought that they come together
like this when food is plentiful.

Many fins will make light work
when hunting large shoals of fish.

DOLPHINS WHISTLE

But getting this many social creatures
together is also a chance for romance.

Females race ahead,
pursued by a group of would-be suitors.

Turning onto their backs the males attempt
some... upside-down mating.

This frenetic open ocean lovemaking
Is so hard to keep up with...

that it has never
been filmed here before...

until now.

DOLPHINS WHISTLE

The females will mate with multiple males.

It won't be the fastest swimmer
who fathers her offspring...

but the one
with the fastest swimming sperm.

Mating over,
it's time to go and hunt some fish.

SEABIRDS CRY
—- CHILDREN SHOUT

Warmer days draw crowds
to the beaches of Pembrokeshire.

But the water /s still cold.

CHILDREN SHOUT

After a long winter it takes time to warm up.

When spring finally comes
to the Celtic Deep...

it triggers a massive bloom Of life.

These murky Welsh waters
might not be crystal clear

but that's because they are
so full of nutrients...

rich with microscopic phytoplankton.

When magnitied around a thousand times

It reveals glassy plant-like cells.

These diatoms contain chlorophyll
with which they photosynthesise.

Just like terrestrial plants

they adraw in carbon dioxide
and release oxygen.

Phytoplankton accounts for around 50%
of all photosynthesis on Earth...

and so, half of the oxygen we breathe.

As they grow, the plant-like phytoplankton
are grazed on by microscopic animals

called Zooplankton.

This in turn kick starts the food chain
in the Celtic Deep.

The plankton's predators come
in all shapes and sizes.

From this thumb-sized comb jelly

to a true ocean giant.

A basking shark.

The second largest fish in the world.

As long as a bus.

This toothless filter feeder is on the hunt
for the microscopic plankton.

And the water Is thick with them.

2,000 tonnes of water an hour
can pass through her open mouth...

and straight out through the gills.

Long, comb-like structures on the gills
then catch the passing plankton.

But to swallow, she needs to shut her mouth

to guip down the catch.

After wintering in warmer,
more southerly waters

the basking shark travels north...

following the blooming plankton
up through the Celtic Deep.

Heading for a summer of feeding

in the shallow coastal waters
around Scotland.

But she isn't alone.

Recent research has revealed

that basking sharks can travel
in extended family groups.

Hanging out with relatives

learning the best migration routes
and places to feed along the way.

When the autumn comes,
this family group will return south.

But for now,
it's time to feast in this sea of plenty.

Jellyfish though, are not on the menu

and even the enormous basking sharks
are careful to avoid them.

They too are here to feast
on the plankton.

Drifting on the currents
to follow the blooms.

The long tentacles of the compass /fellyfish
are equipped with stinging cells

for capturing Zooplankton
and even small fish.

As if from another world, a moon jellyfish

one of the most common to be found
around the Welsh coast.

When food and conditions are good

they can be found in swarms
of many thousands.

In recent years,
the number of jellyfish has increased...

suggesting an imbalance
in the health of our seas

linked to pollution,
overfishing and climate change.

But one creature able to take advantage
of this is following in their wake.

The ocean sunfish,
with its bony, beak-like mouth.

Perfect for biting off lumps of jellyfish.

It's the size of a dinner plate,
but can grow as big as a Car.

A brief summer visitor to the Celtic Deep.

He loves nothing more than gobbling up
gelatinous splodges.

SEABIRDS CRY

The explosion of life just offshore
has not gone unnoticed.

Sardines are arriving in their millions.

Fishing boats are drawn out here
from far and wide.

These shoaling fish have travelled en masse
from deep water off the Isles of Scilly...

here to feed on the plankton.

They also promise rich rewards
for those that can catch them.

An old traveller has returned
to the Celtic Deep.

This Is a six-foot long
Atlantic bluefin tuna.

Extremely partial to sardines.

These are the ultimate open ocean hunters.

Fished to near extinction

they've not been seen regularly
in these waters for over 30 years.

But now the tuna are back.

Drawn here by the bounty on offer.

BIRDS CAW

Splashing on the surface announces
the arrival of the tuna...

but only hints at the carnage
about to be unleashed below.

Using their formidable power
to generate massive acceleration

they are able to pick off the fish at will...

preferring to swallow their prey whole.

Tuna are highly migratory...

perfectly adapted to wander the oceans
in search of the most productive waters.

For these tuna,
the Celtic Deep is the place to be.

Following the tuna and the panicked fish
are the gannets

hoping for an easy meal.

GANNETS CAW AND CRY

The gannet must pick its moment carefully.

Dive-bombing on a moving school of fish
requires precision.

Hitting the water at 60 miles an hour

allows them to reach fish
up to 20 metres down.

Under aerial bombardment, what remains
of the bait ball of fish dives deeper.

But there's one bird determined
to follow them.

A Manx shearwater.

Preferring to duck dive from the surface...

it can swim down to 55 metres
to hunt fish

far beyond the gannets' reach.

GANNETS CRY

The shearwaters are accomplished
long distance navigators

spending the Welsh winter off the coast
of South America

before returning to the islands
of the Celtic Deep to breed.

DOLPHINS WHISTLE

Now the common dolphins arrive.

But a moment too /ate.

A minke whale engulfs the surviving fish
in one massive mouthtul.

The minke is the smallest
of the baleen whales

found in the Celtic Deep.

But at over ten metres long,
she’s still a giant.

With the fish consumed,
the feeding frenzy is over.

The smell of the carnage has drawn
the attention of another ocean wanderer.

A blue shark, over two metres long.

Her powertul sense of smell
has drawn her here.

Highly sensitive to the amino acids
found in blood

she can follow a scent
on the current for miles.

She's not interested in the departing tuna.

Found throughout the world

this elegant ocean predator is looking
for a starter before her night-time banquet.

She will be more active after dark

hunting tish, squid and even other sharks.

But right now

she'll not turn down the opportunity
for wholesome scraps.

A nomadic wanderer

the Celtic Deep is her summer hunting ground.

She doesn't appear
until the water's warm enough

and disappears as soon as it starts to cool.

With little left to be found in the remains
of this bait ball, she cruises on.

The fish remains and dead plankton drop
slowly towards the sea floor.

This "marine snow" is full of nutrients.

A bottom dwelling weeverfish,
rarely seen swimming freely.

[ts six poison-tilled spines
make it the scourge of many a beachgoer.

30 metres down

and the sea floor looms
in the near darkness.

Here, another shark patrols
what appears to be a desolate landscape.

A metre-long starry smooth-hound.

But on closer inspection

this sea floor is a thriving carpet of Iife.

Thick with horse mussels

some up to 50 years old.

Eerily decorated with a white, soft coral
known as dead men's fingers.

Living half-buried in the sea floor

the horse mussel beds provide
a reef-like structure

for a whole community of creatures.

Providing shelter...

for some.

It is thought
that much of the Celtic Deep floor

once looked like this.

But when damaged by fishing nets
dragged across the sea floor

the slow growing horse mussels
and the habitat they create

struggle to recover.

But where it remains

it is host to a thriving
ocean waste management community.

Life down here relies on
what arifts down from above.

Clams, like the mussels,
feed on passing plankton.

Transparent sea squirts are also
filter feeders.

And as if on guard around them

squat lobster snatching food
passing in the current...

eating the sea floor clean of debris.

Hermit crabs take recycling
to the next level.

Their mobile homes are empty whelk shells
covered in barnacles...

making this a moving, living landscape.

Here, there's a hungry mouth
for every scrap of food.

Nothing goes to waste.

A scorpion spider crab.

These curious crabs stick bits
of living sponge to themselves.

The sponges then grow to cover the crab.

Adding to the camoutiage,
the crabs pulse up and down

waving like plants in the current.

Blending in is key for survival.

With a hungry catshark on the prowl,
It pays to lie low.

A curled octopus waits it out between meals.

Others are bolder...

showing no fear of sharks.

A red gurnard.

Where others swim,
this fish prefers to walk.

Equipped with sense organs
in their finger-like spines

they can feel for prey
hiding among the mussels.

There's plenty around.

It takes more than fish fingers
to make the catch.

Second time lucky.

Deploying a similar strategy
but with deadlier weapons...

the curled octopus is out of hiding.

She is a ruthless hunter

with a keen eye for anything that moves...

and for anything that doesn't.

She has eight taste-sensitive tentacles
that feel their way across the reef.

Hidden under her mantle,
her tough, bony beak is strong enough

to crack through crab shells.

She can immobilise prey
with an injection of toxins

before digesting their dissolved flesh.

But when crossing the reef,
she's exposed.

To stop the hunter becoming the hunted,
she must always be on her guard.

Other predators continue to /urk.

She is a master of disguise.

With a lack of hiding places

she must rely on her ability to change colour

and blend in with the surrounding shells.

Now you see me...

now you don't.

[t's now mid-summer

and just off the Irish coast

a remarkable and rarely witnessed gathering
ls spotted from the air.

Over a dozen adult basking sharks are
circling in descending layers.

With mouths shut

these sharks are not here to feed.

This seldom-seen behaviour is thought
to be a courtship ritual.

Very little is known about the sex life
of basking sharks.

The females give birth to live young

but the mating itself
has never been witnessed.

This helter-skelter of basking sharks
Aisappears into the depths.

Perhaps, down below this circle,
the next generation will begin their lives.

During the summer, new life abounds
in the Celtic Deep.

The microscopic plankton is full
of tiny, newly hatched animals.

This bug-eyed creature will become
a spider crab.

/t carries a rapier spine
to deter would-be predators.

Until it becomes an adult crab

and a real hard case.

Other familiar seaside animals
are found here.

Crabs, shrimps, urchins and starfish

all spend the first part of life
arifting with the plankton.

At the mercy of the open ocean.

The tiny youngsters are here
to feed and grow.

These speedy juveniles are the larvae
of the static barnacle.

As adults they are firmly glued
to a suitable surface

so this is their chance to get far away
from the parents.

They spend this time eating and defecating.

lf they survive this juvenile phase

the barnacles and crabs will descend
to the sea floor.

Where life continues to be treacherous.

Millions of adult barnacles cover
the horse mussel beds

providing a tempting buffet for those
with the tools to take them on.

On the march,
a chain of onchidoris bilamellata nudibranch.

Don't be fooled by their sluggish appearance.

This is a herd of voracious predators

easily able to outpace their prey.

The onchidoris are rnasters
of chemical warfare.

Absorbing the foul-tasting poisons
of their prey

they then secrete these as a defence
against their own predators.

With this for protection,
an onchidoris is a bold hunter...

specialising in devouring barnacles

no matter where they grow.

Despite their armour,
barnacles are no match for the onchidoris.

It has a special tooth which chews away
at the top plates of the barnacle

before sucking out the soft tissue inside.

Terrorising the reef
at their own leisurely pace

the onchidoris still need to be careful.

This common crab has apparently developed
a tolerance for toxicity.

In this world of scavengers,
even the best defences are not always enough.

Some prefer to come fully armed.

Another plankton arifter has survived
to wander the sea floor.

An eagle-eyed,
sharp-shooting mantis shrimp...

more commonly found in warmer waters.

This colony in Cardigan Bay
was only discovered in 1999.

An ambush hunter,
he's equipped with a harpoon-like claw

with teeth-like serrations along its edge.

But to deliver the killer blow,
a good aim is required.

And this quicktire crustacean has
the most advanced eyesight on the planet.

Each independently moving eye is
made up of

tens of thousands of photoreceptor cells...

allowing it to see ultraviolet,
infrared and polarised light.

And for accuracy,
three pupil-like receptors in each eye

allow it to measure distances perfectly.

With nothing in range,
he decides to hide out...

waiting for an unsuspecting victim.

PEOPLE YELL

The long, hot days of summer are
drawing to a close.

And the beaches of Abersoch
have drawn in the crowds.

Tourists, here to revel
in the last of the sunshine...

and the now warm sea.

SEABIRDS CRY

For those gathered out in the Celtic Deep

they too are keen to make the most
of the last days of summer.

Common dolphins

seeking fish.

DOLPHINS WHISTLE

Using echolocation, they are homing in
on a school of sardines.

DOLPHINS WHISTLE

DOLPHINS CONTINUE WHISTLING

Under attack, the fish form a defensive ball.

The dolphins work together to corral
the sardines close to the surface...

until they have nowhere left to go.

The dolphins take turns
to plough through the bait ball...

using their tails to create shock waves...

and stun the fish.

The commotion does not go unnoticed...

acting as a dinner gong
echoing across the sea.

BIRDS CAW

The gannets and the shearwaters are soon
on the scene.

DOLPHINS WHISTLE

And with fish trapped against the surface
they throw themselves into the fray.

BIRDS CAW

DOLPHINS WHISTLE

BIRDS CAW

The sound of the splashing travels faster
and further underwater.

The bluefin tuna arrive

as big as the dolphins
and with an insatiable appetite.

But they are dwarfed by the next arrivals.

Fin whales.

At 25 metres /ong,
only the blue whale can rival it for size.

They are here to capitalise
on the dolphins’ hard work.

Lunge feeding on its side enables a whale
to sieve through

its body weight in water in one mouthtul.

For a brief moment

the visitors and residents
of the Celtic Deep feast together.

In a few weeks the fish will be gone.

They must eat while they can.

With nothing left, the party disperses...

to continue travelling the Celtic Deep.