All language subtitles for Great Rivers II.s01e02.Danube

Earth's great rivers...

..make extraordinary journeys...

..carving through continents,

feeding and connecting life...

..nurturing culture...

..providing a place for adventure.

From the frozen wilderness of the
Yukon...

..to the tropical heat of the
Zambezi...

HIPPO GROANS

..and the magical, hidden worlds of
the Danube.

Great rivers are the lifeblood of
planet Earth.

The majestic Danube...

..almost 2,000 miles long, from source
to sea...

..running through the heart of Europe.

So much more than a single river.

The Danube is a giant network of
water,

reaching out across the continent.

Flowing east from Germany and Austria,

all the way to Romania and the Black
Sea.

Its tributaries gather water from 19
countries...

..making it the most international
river on Earth.

On its journey, it will cross
formidable landscapes

and ancient kingdoms...

..revealing glorious riches

and magical surprises.

But to follow the ever-changing face
of this unique river...

..we start at the very top.

Over 4,000 metres above sea level,

Piz Bernina Mountain in Switzerland

is the highest point of the entire
Danube system.

Here, 800 million tonnes of water

is locked in...as ice.

Four miles long and 250 metres deep,

the Morteratsch glacier, for most of
the year,

is covered in deep snow.

But when temperatures rise in spring,

and conditions are just right...

..there's a window of opportunity.

- Running keeps me alive.

It connects me with nature and
connects me with my own spirit.

- Anne-Marie Flammersfeld has spent
most of her life running

the world's toughest landscapes.

Today, she is seizing her moment

to run on the frozen headwaters of the
Danube.

- Running on a frozen river, it's
something really weird

because it's only there in a special
period of time.

- It looks beautiful,

but looks can be deceiving.

- Even in the summertime, running on a
glacier is really dangerous.

You don't know where the crevasses
are.

When you fall into a crevasse, you can
fall for three or five metres.

- So it pays to follow a planned
route.

- I always try to look for the best
line when I run downhill

because I run downhill really fast,

and I really enjoy it, and then my
eyes are concentrated

on every step and, tak, tak, tak.

And, uh, yeah, this is most of the
fun.

- As she nears the base of the
glacier...

..there's a glimpse of the true power
locked up in the ice.

- When you look into it and you see
that the water

is coming from somewhere

and you think, "Ah, it's a river."

- Beneath the glacier,

the headwaters of the Danube are on
the move.

More than a quarter of the river's
water

comes from the Alps.

And, in spring, it becomes an
unstoppable force of nature...

..fuelling the flow of the Danube
across the continent,

all the way to the Black Sea.

Its journey has only just begun.

A few miles away,

on the slopes of the valley below...

..the melting snow...

..makes way for new beginnings...

..revealing...

..someone's home.

Inside is a creature who has been
waiting to come out...

..for nearly eight months.

A male alpine marmot.

They may seem small,

but, growing up to 8kg,

these are the heavyweights of the
squirrel family.

Winter has not been easy on him and
his kind.

Alpine marmots lose about a third of
their body weight,

stuck in their burrows during winter.

Now, he needs to fatten up.

The melting snow has uncovered
valuable food.

Marmots eat grasses, flowers,

and even a worm or two...

..if they can find them.

But there's a problem -

other families live here, too.

With only so much food to go around,

he'll need to defend his territory.

And when it comes to protecting home,

marmots mean business.

An intruder approaches.

It's time to go on the offensive.

To get an advantage...

..marmots rise up and stand tall.

Here in the valley, it's hand-to-hand
combat...

..each pushing and grappling.

Now, keeping your footing is
everything.

But just when the coast seems clear,

there's more danger.

The heat from the sun now causes giant
icicles

to fall from frozen waterfalls.

A blow from one of these would spell
disaster.

Crisis over.

In the valley of the marmots,

life is looking good.

As the meltwaters run on...

..they join countless other streams
and tributaries...

..flowing from all corners of the
Danube system.

Passing through a myriad of habitats,

some of which hide secret wonders.

In the forests of Bosnia,

one Danube tributary has a very
different source.

These crystal clear waters are fed by
underground springs...

..creating a magical water world.

Legend has it that the Romans were so
stunned by this river's beauty

they named it Una, meaning "The one."

While the water may look clear,

it's full of dissolved minerals from
the limestone below,

producing a special kind of river

with miniature waterfalls and pools.

As water flows over moss and other
plants,

the dissolved minerals are gradually
absorbed

and collected by this natural sponge,

which hardens and builds...

..eventually forming whole new
waterfalls.

It's like something from a fairy tale.

But not everything to see here is
above the water.

Below, there's a party under way.

The nutrient and oxygen-rich
headwaters of the Danube

create the perfect place to gather and
search for food.

Golden shoals of barbel

mix with graceful grayling, and busy
trout.

Many use these fresh waters to
spawn...

..including one species

found nowhere else on Earth.

Each spring, if you look carefully,

you'll find one of the river's top
predators.

The huchen, also known as the Danube
salmon,

can grow over a metre long.

The largest freshwater salmon in the
world.

Today, this pair are showing their
softer side.

With her powerful tail,

the female sweeps away the gravel

to make a small depression in the
riverbed.

A nest in which to lay her eggs.

Very soon, the riverbed looks like
it's had a spring clean.

The male joins her to mate...

..and guards her from any unwanted
attention.

But then...

..perhaps it's best to leave these
giant predators to it.

The secret waters of the Danube
provide a bounty

of opportunity for life.

And where there are fish...

..others will surely follow.

Today, Zdena Gavranovic is hoping to
catch a fish

that thrives in crystal clear waters,

the trout.

She starts by making some fishing
flies.

IN CROATIAN:

IN ENGLISH: Her aim is to make the
perfect insect...

..something that might just trick a
trout to eat it.

IN CROATIAN:

Tiny feathers for the wings and silk
for the body.

Solid enough to look the part,

yet delicate enough to cast.

Now, time to put them to use.

First, she casts out her line...

..with a loop in the air.

Released on to the water as light as
she can...

..placing the fly to entice her
quarry.

Fly fishing is a special kind of
fishing.

IN CROATIAN:

Timing and rhythm are everything.

Each cast lets out a little more
line...

..a little more hope.

IN CROATIAN:

No luck this time, not that it
matters.

When a river is as beautiful as this,

that is rewarding enough.

While some are drawn to the
tranquillity of the river,

the waters of the Danube constantly
change.

In Slovenia, one of the Danube's
largest tributaries,

the Sava, offers an entirely different
experience.

- Woohoo-hoo!

- Like the rushing waters around him,

kayaker Rok Rozman finds a freedom
here.

But it's not without risk.

- There might be trees in the rapids,

which can be really dangerous.

There's some rocks that produce
siphons.

So, like old people said,

the river is full of traps.

But, at the same time, the river is
full of joy.

People who meet the river in a kayak

will always see the river differently.

- For Rok, who is also a biologist,

rivers bring so much more than just
enjoyment.

- Cos the river has the most abundance
in diversity

and life out of any habitat, you know?

Transporting nutrients, water, energy,

it's the most important part of
nature.

- And when faced with the pressures of
life,

Rok also believes the river can help.

- If you have problems,

you can go and talk to the
psychiatrist,

or you can go and sit next to the
river.

It's up to you what's nicer, cheaper,
and better.

- As they flow down from headwaters
and alpine valleys,

the Danube tributaries finally come
together

to become this great river.

Towns...

..farmland...

..and cities begin to line its route.

Over thousands of years, people have
settled on its banks

and have tamed the river...

..straightened and engineered

to help protect against annual
flooding.

But there are still wild places here.

Just outside Austria's capital,
Vienna,

lies Danube-Auen National Park.

A strip of protected forest and
wetland

on the banks of the Danube...

..home to some extraordinary
creatures.

EARTH CRACKLES

A baby European pond turtle.

Buried as an egg four months ago,

it's now hatched and free.

Its mother chose a nesting spot that
would be safe from flooding...

..but now it's far away from water.

And this tiny creature needs to go on
an epic journey...

..all on its own.

But when you're the size of a
thumbnail,

everything is so much larger.

Even tiny ants are a big deal.

But this turtle comes with its very
own suit of armour.

Its arms and legs might be small,

but they are powerful.

Using all its energy,

it instinctively heads towards water.

Out of all the baby turtles that hatch
every year,

only 2% will make it to adulthood.

And just when you think you've made
it...

..the finish line seems so very far
away.

And it's not just the turtles on the
move.

BELL RINGS

Now or never.

A close shave.

Fortune favours the brave.

Critically endangered in Austria,

every turtle that makes it counts.

At last,

cool and refreshing water.

It might seem unfamiliar to our young
turtle,

but, finally, home.

Safety, food, and even some friends.

Having passed through Germany, Austria
and Slovakia,

the Danube is now at the midpoint on
its great journey

and arrives in Hungary...

..at the majestic capital of Budapest.

A city that owes its existence to the
Danube

and has seen empires rise and fall,

from the Romans to the Crusaders.

In Budapest, art and romance
intertwine.

Grand architecture,

and no less than seven bridges,

showcase a place that has been the
source

of cultural inspiration down the ages.

Today, with a population of 1.7
million,

it is as important as ever.

Water might be one of the oldest means
of transport,

but it's still the cheapest.

And Budapest, because of its unique
location,

is key to the Danube's continued
success

as the backbone of the European
transport network.

Up to 50 million tonnes of freight are
transported

along the Danube each year.

Giant cargo ships and barges sail from
port to port...

..carrying large and heavy loads,

like cereals, sand, and fuel

that would otherwise have to take less
economical routes.

Dockyards act as transport hubs,

where shipping containers and goods
are ferried like clockwork.

A giant, moving jigsaw puzzle,

working 24 hours a day,

seven days a week.

It's easy to see the importance of the
Danube

to everyday life in Budapest,

but there is more.

A secret, hidden from view.

A shaded pool is hard to spot.

But, for two scientists,

it's an ancient wonder that connects
the Danube

to the last Ice Age.

To explore it...

..Dr Gergely Balazs

and Dr Denes Szieberth

need to put on specialised equipment

as they prepare to enter a cave

that is completely filled...

..with freshwater.

The Molnar Janos caves only started to
be explored in the 1950s,

with the invention of suitable diving
equipment.

- We have this busy city on the top of
it.

But the cave, it's an ancient thing.

- Crystal clear water,

filtered through rock over millennia,

stretches for almost four miles right
under Budapest.

And there's more to be discovered with
each dive.

- Some of the passages here are huge,

and the water is so clean that you
don't even see

that you are in the water.

So you are just flying through these
huge spaces.

- The caves offer unique opportunities
for the scientists.

- You see things which no-one have
seen.

You make measurements which no-one had
the opportunity to make.

This is pure exploration.

- Despite the challenges,

the scientists have already begun to
unlock

the secrets of these waters...

..concluding that over a million
litres of water a day

flows imperceptibly through the caves.

And, in Budapest, there can only be
one destination.

- There is an obvious connection.

The cave feeds a lake,

which, through a channel under the
Locash bath,

the water of this lake is flowing
directly into the Danube.

- A hidden tributary...

..joining the Danube on its great
journey downstream.

Here, in Hungary,

the Danube's waters may seem slow and
sluggish...

..but they still have the ability

to conjure up moments of wildlife
magic.

On one of its middle tributaries...

..there's an animal that produces

one of the most spectacular natural
events on Earth.

IN HUNGARIAN:

IN ENGLISH: Freshwater scientist Dr
Bela Kiss

is trying to find some of them.

Bela monitors the population of an
insect

that hides underwater for up to three
years.

But, to do that...

..he has to dive down over four metres
to the riverbed.

IN HUNGARIAN:

IN ENGLISH: It might not look like
much...

IN HUNGARIAN:

IN ENGLISH: But in a few months, these
larvae will transform

themselves to become one of the
largest mayflies in the world.

For just a few days in June...

..when the water temperature rises,

they begin to hatch.

First, the males take flight.

IN HUNGARIAN:

IN ENGLISH: For some...

..life is very short indeed.

Soon, more and more appear from the
water.

There's no time to hang around.

They have only three hours to live

and just one purpose...

..to find a female and mate.

The search for newly-hatched females

begins a frenzied mating dance.

The sky soon becomes thick, with
several million mayflies

all mating in groups.

Once common in many parts of the
Danube system,

pollution and habitat-loss

mean this great event is becoming
harder to find.

But if you know where to look...

..it's an astonishing super-swarm of
life.

IN HUNGARIAN:

As quickly as it began,

this remarkable event...

..is over.

After a three-year wait,

it's a short existence,

but it's a life well-lived.

In just one day, they have flown,

mated and died.

By this stage on its journey,

the Danube has been joined by its
major tributaries,

the Drava, the Tisza...

..and the Sava.

Combined, they almost triple its flow.

As it reaches its third and final
capital city,

Belgrade, in Serbia.

Over half a mile wide,

discharging 5.5 million litres per
second.

This now mighty river...

..flows on towards the border with
Romania

and one of the last great landmarks on
its epic journey.

The Iron Gate gorge.

90 miles long, yet narrowing to just
150 metres wide.

For thousands of years,

all traffic on the river had to pass
this daunting gateway.

The narrow gorge, with towering
cliffs,

was infamous for its dangerous rapids
and whirlpools...

..making passage in a boat extremely
treacherous.

But in the 1970s,

this part of the Danube was changed
forever...

..when engineers harnessed the river's
power

and created the Iron Gates Dam...

..one of the largest hydroelectric
plants in Europe.

This giant feat of engineering

produces five and a half million
megawatts of electricity,

relied upon by 25 million people in
Romania and Serbia.

A super-structure that has had an
impact on both people...

..and the river.

Below the dam,

the Danube enters the lowlands of
Romania and Bulgaria.

In these waters, there is one group of
animals

that has been deeply affected by the
man-made barrier upstream.

A true monster of the deep...

..the sturgeon.

Some species of sturgeon, such as the
Beluga,

live for over 100 years and grow up to
six metres long,

the size of a shark.

But it's their eggs that have made
them famous,

sold as luxury caviar,

and shipped around the world.

As one of the major rivers draining
into the Black Sea,

the Danube is a vital spawning ground
for sturgeon.

But overfishing, pollution and the
construction of dams,

which have blocked them from their
spawning grounds upstream,

mean this river giant has all but
disappeared.

Now, sturgeon are thought to be more
critically endangered

than any other group of species...

..on the planet.

For one person, their future is
something worth fighting for.

- It's my passion.

I want to do it all the time.

- Borislava Margaritova,

a fish biologist working in Bulgaria,

is trying to conserve the health of
the Danube and its fish,

especially four species of extremely
rare sturgeon still found here.

- The Danube is the last river

in Europe that they spawn naturally.

So we try to protect them because
they're very rare now.

- Today, she's going out with her team
to survey the river.

- We are on the river at five in the
morning

and we work most of the time until the
evening time,

ten in the evening.

It depends what we catch.

- Using nets, they hope to find some
fish for their research.

But in such a large river,

and with a small team,

it's not going to be easy.

In nine years of doing this work,

Borislava and her team have only ever
caught six sturgeon.

- It's very difficult.

You spend eight, nine hours on the
river, on the boat,

and you pick up the nets, and you see
the empty nets.

It's very frustrating for me.

- But there is always hope.

And today is a very special day
indeed.

- Yes!

- HE SHOUTS

THEY CHEER

Incredibly, the team catch not just
one sturgeon, but two.

Smaller than the famous Beluga, but no
less precious.

A young sterlet sturgeon,

estimated to be between three and five
years old.

And a starry sturgeon,

between five and seven years old.

- Woo!

- It's a huge result for the team.

- We try to catch these specimens for
months,

so it's very rare.

We are lucky.
- Ah-ha!

- It's like when somebody have a
birthday

and you have this present that you
want for many,

many years...

- HE CHEERS

- ..and you have it, and it's not only
one, you have both.

- They use their precious time with
the fish

to record important data,

including size and weight.

And carefully attach tags,

so they can monitor the fish's
movements.

The significance of this unique
encounter is not lost on Borislava.

- The sturgeons are like a flagship on
the Danube.

So, if the sturgeon are still here,

we will know that the river is
healthy.

- There is a way to go.

But, for now, Borislava can celebrate
this small victory.

- Bye, baby.

- It's hoped that conservation
efforts,

like restocking and protecting
migration routes,

might just give these iconic fish a
future.

The Danube has finally arrived

at the last stage of its epic journey,

saving the greatest transformation
till last.

The Danube Delta.

Passing through Romania and Ukraine,

this mighty river finally breaks free.

At almost 2,000 square miles,

this is the largest undisturbed
wetland in Europe.

Only fully accessible by boat.

Narrow channels pass through riverine
forests

of willow and poplar.

Opening out into freshwater marshes...

..fringed with reedbeds...

..and vast lakes covered in water
lilies.

One of Europe's least inhabited
places...

..giving space for wildlife to thrive.

More than 5,000 animal and plant
species are found here.

The Delta is a globally important
destination for birds,

some migrating from as far away as
Africa and Asia to breed,

like Whiskered Terns and Squacco
Herons.

And one bird that has made the Danube
Delta its own.

The Great White Pelican.

With 17,000 breeding pairs...

..this is the largest colony in the
world

outside of Africa and their numbers
are increasing.

For just a few months,

they'll nest here and feed on the
Delta's bounty...

..working together in giant flotillas
to feast on fish.

A glorious spectacle at the end of the
Danube's great journey,

before, once more, they head into the
Black Sea and beyond.

The Danube's waters have flowed
through more countries

than any river on Earth...

..through a continent separated by
borders

and changed by humanity.

Despite these challenges,

always finding a way to keep going...

..to inspire...

..to nourish...

..and even astonish.

One continent connected and united...

..by water.

The Danube and its tributaries cover
19 countries,

creating the most international river
system on Earth.

To capture its secret hidden worlds,

Earth's Great Rivers teamed up with
local crews,

contributors and experts right across
Europe...

..the people who know the Danube best.

But it was in Slovenia

that they met one person who revealed

a different side to the Danube
story...

..a threat that could affect its
future,

as well as many other rivers around
the world.

Biologist and former Olympic rower -

Rok Rozman.

- It's this mighty river that I call
home.

The meaning of it is just extremely
big in every way.

- Rok has lived all his life on the
Sava river,

one of the Danube's major
tributaries...

..and he knows it as well as anyone.

- Sava is really special

because it brings everything that's
stored high up in

the mountains down to the bottom of
the valley.

Without Sava, this valley wouldn't be
green

and we wouldn't have pastures,

and we wouldn't have tourism.

We wouldn't be kayaking,

we wouldn't be fishing,

we wouldn't be enjoying the sound of
the river.

It's basically the essence of this
place.

Woohoo-hoo!

- But it isn't just Rok who takes
advantage of the power of rivers.

Over the years,

engineers have harnessed them across
Europe

as a source of energy...

..building dams -

a valuable and low carbon source of
electricity...

..and a way to store water and help
control flooding.

But dams will always create winners
and losers.

And these barriers have complex
implications...

..dramatically reshaping the river's
ecology

up and downstream...

WHISTLE TOOTS

..which is a concern

for many who live alongside these
rivers.

The Sava river already has over ten
dams

and there are plans for ten more.

For Rok,

the damage caused by these barriers to
the wildlife

and ecology of the river is too great
to ignore.

- It would be sad to see

such destruction to this river, you
know?

The river provides home for these
animals.

You know, they can't go anywhere else.

If a bird lives on a gravel bar, well,

then it lives on a gravel bar.

If an otter needs a river with fish,
well,

then that's what this river provides,

and that's why it's so important to
protect these rivers.

And by the time we realise

the negative effects, it's already way
too late.

And it just...

..breaks my heart and mind. Erm...

Because if these plans go ahead,

the place where I'm sitting right now
will be underwater.

And it's not just me, I'm the last in
line, you know?

My enjoyment in kayaking is the last
in line.

There's fields here, people depend on
these fields.

There's an otter family living there.

Where will the birds go? Where will
the plants go?

- Free-flowing rivers can be hard to
find in Europe.

Recent research has suggested more
than a million barriers

fragment the continent's rivers.

The Danube and its tributaries

have seen more than 700 dams

and weirs built along their course.

The effect of these man-made
structures

on wildlife is significant.

Faced with this, Rok decided to do
something.

- I realised that emotion without
action

is basically going to ruin your soul
eventually,

and I called a bunch of my friends and
I said,

"Look, guys, these rivers are going to
be destroyed without

"anybody knowing if we don't do
something."

- CHEERING

- We realised that the core of the
problem is that

there's not enough people spending
time next to the river

and we said, "Well, we're going to
take people rafting.

"We're going to take people picnicking
by the river.

"We're going to take them kayaking,
swimming, whatever."

You first need to know a place

to fall in love a place

and only then you're going to feel the
need to protect it.

- Rok's initiative has already helped
stop

the building of 12 new dams in the
region.

And one of the dams on his home river,

the Sava, has now been delayed.

But it's also focused attention on

the importance of allowing rivers to
flow naturally.

Along with lakes and wetlands,

rivers cover less than 1% of the
planet...

..and yet are home to a quarter of all
vertebrate species...

..including over half of all species
of fish.

- Hydro is seen as a renewable source.

Their intentions might be good,

but the reality is that what we're
doing is, basically,

we're destroying the most important
parts of our environment.

- Hydropower is a major low-carbon
source of electricity,

but as decision makers are coming to
understand

the value of free-flowing rivers...

..its use is being reassessed.

And a revolution in renewable
technologies

may offer exciting alternatives...

..like solar...

..wind, and battery storage,

which could all help keep rivers
flowing.

- My hope for the future is that
people realise

the importance of rivers for
themselves...

..then also for all the wildlife and
plants,

and whatever lives next to it...

..because the time is running out.