All language subtitles for Wild South America 4 The Andes

This is a journey down
the longest mountain chain on earth.

These are the Andes
the spine of South America.

They span the length of the continent
over five thousand miles

from the tropics
almost to the Antarctic.

Surviving in the Andes is one of the
greatest challenges in the natural world.

It's a truly hostile place to live
bitter cold, thin air, relentless wind

...even the volcanic forces of
the earth itself.

Faced with trials like these

how can anything survive here
let alone flourish?

Our journey begins in the tropics
at the northern end of the range.

The highest peaks in the Andes rise to
nearly seven thousand metres.

And some are still growing.

Measured on the scale
of geological time

the Andes are still young.

The mountains mark a line

where two great
plates of the earth's crust collide.

The impact crumples the continent
and huge volcanoes break through.

As the mountains rise into the clouds

their slopes are colonised
by forest

cloud forest.

In the warmth of the tropics
trees can grow high on the mountains

to well over three
and a half thousand metres.

Animals were quick to exploit the new
opportunities these forests provide.

Isolated in a maze of ridges and valleys
all sorts of new species developed.

These Andean cloud forests rival
the Amazon rainforest for diversity.

There are more kinds of hummingbird here
than anywhere else in the world.

Almost every hillside has its own
unique plants and animals.

The cloud forest also
has its very own bear

the spectacled bear
named after the markings on its face

This is the only bear in South America.

There are just a few thousand left.

Most kinds of bear are good tree climbers

but here that skill is essential.

Spectacled bears get much of their food
from the treetops

so climbing trees is one of the first
lessons this baby has to learn.

The cub is well grown

but it still has a long way to go to
match its mother's skills.

The trees here can be twenty metres high

so it can't afford to make a mistake.

These high forests have few monkeys

so there's plenty of food for bears
that are willing to climb.

But for an animal that can weigh well
over a hundred kilos

that's quite a challenge.

Even when it's mastered
the art of climbing

the cub still has to learn
what to eat.

The bears' favourite food
are bromeliads

plants that perch on branches high
in the canopy.

They're especially fond of
the fleshy base of the leaves.

Bears are adaptable animals
and there's only one kind here.

Other animals are more specialised

so several species can coexist
like the hummingbirds.

These damp cool forests
have few flying insects

so many of the flowers rely on birds
for pollination.

Plant and pollinator
have a unique relationship.

Each hummingbird's beak is perfectly

adapted to reach the nectar
in its chosen flower.

As the hummingbird moves
from flower to flower

it transfers pollen
and so fertilises them.

In exchange

it gets sugar-rich nectar
to fuel its hovering flight.

At high altitude, the air is thinner
and has less oxygen.

It's hard to hover.

Most bromeliads win their place in the sun
by growing high in the trees.

But some kinds have gone a step further.

They've left the forest behind
and climbed the mountain.

The puyas grow in the paramo

a zone of alpine grassland
above the forest.

After several years

they throw up a stupendous five metre
flower spike... and then die.

With just a once
in a lifetime opportunity

it's vital
that the flowers are pollinated.

Puyas have their very own hummingbirds

like the Andean Hillstar.

It lives higher
than any other hummingbird.

Up here the air is even thinner
and hovering is even harder.

So whenever it can
it perches rather than flies.

As it moves from flower to flower
it transfers more than pollen.

Tiny pollen-eating mites
live in the flowers.

They crawl onto the hummingbird to
hitch a lift to another plant.

At the next stop, some passengers get off
and others get on.

Not every animal works
in such harmony with the puyas.

The growing flower spikes are
an irresistible honeypot

for spectacled bears.

They can destroy a
lifetime's work in seconds.

For bear cubs, learning how to tackle
puyas brings a sweet reward.

The spikes are rich in sugar

to make nectar
for the hundreds of flowers.

They're packed with energy
but how do you get at it?

A little parental guidance
is called for.

Spectacled bears are versatile animals

but each new generation has to
learn the tricks of the trade.

The mountains are an
unpredictable place to call home.

Massive volcanoes rise
above the cloud forest.

At any moment
they can burst into violent life.

As you travel south down
the chain of the Andes

you pass a line of brooding giants.

Among them are the highest
active volcanoes in the world

rising to more
than six thousand metres.

They're so high that even
in the tropics

their summits are crowned
with ice and snow.

In the heart of the Andes

volcanic activity has built more
than mountain peaks.

It's thrust a high desert plateau

three miles up into the sky
the Altiplano.

Sulphurous steam from the world's highest
geyser field rises into cold

thin air... a vision of earth
before life began.

Much of the water here evaporates
in huge caustic lakes.

This must be one of the most
extreme environments on earth.

How could anything
possibly live here?

Incredibly

the Altiplano salt lakes
actually attract animals.

Flamingos come here to breed.

Their season starts
with a massed courtship dance.

Three kinds of flamingo nest
on these caustic lakes.

These ones are Andean flamingos.

These lakes are prime flamingo habitat.

With no outlet
dissolved salts washed down

from the surrounding mountains are
concentrated by evaporation

ideal conditions for the flamingos
favourite food - brine shrimps.

They thrive in water ten times
as salty as the sea.

The birds catch them by filtering water
through bony combs in their beaks.

The three kinds of flamingo
have different sized 'filters'

so they can live together by exploiting
different parts of this briny soup.

Only a handful of other waterbirds
can live here.

Andean avocets subsist on fly larvae.

The key to success up here
is being a specialist.

Brine flies live in a world
that's wafer-thin

sandwiched between the salt
and the piercing wind.

But their swarms are large
enough to support a lizard.

Brine flies are its staple diet.

Being cold blooded

it hunts only when the temperature
has risen enough for it to move.

For a lizard living on the edge
of what's possible

even a patch of fly-blown salt pan
is worth fighting for.

Even the steaming outflow
from a geyser attracts life.

This frog also survives on flies

but this really is living on the edge.

A few hops one way
and it would be boiled alive

a few the other
and it would freeze to death.

This desert on the roof of the world
even has mammals

Vicuna
South American relatives of the camel.

But what can they eat up here?

There's more to the Altiplano
than caustic lakes

and not all the springs
are hot and salty.

Fed by meltwater from the snow-clad peaks
some run cold and fresh.

They water small patches of marsh
called bofedales.

In the drier parts of the Altiplano

these green oases are the key
to the vicunas' survival.

They provide grazing
and fresh water to drink.

All sorts of animals depend on them.

Like viscachas
rabbit-sized rodents.

Early in the morning
the marsh is frozen hard

so the viscachas bask in the sun
until the ground warms up

along with the leaf-eared mice
that share their jumble of boulders.

Only when the grass has thawed
can they start to graze.

In the drier parts of the Altiplano
little grows away from the bofedales.

The few flowers give a sip of nectar
for the Andean Hillstar.

Up here perching is vital to
save energy in the thin air.

There may be no woods here

but there is a woodpecker
the Andean flicker.

It nests underground
and hunts for insect grubs in the marsh.

At this extreme altitude

the main problems any animal has to
face are cold and lack of oxygen.

Viscachas overcome the cold
by having incredibly thick fur

but they have to keep it in good shape
if it's to save them from freezing.

To make better use of the thin air

some animals have a high concentration
of red blood cells

and specialised lungs.

It also helps
if you don't exert yourself.

Viscachas hardly ever move more

than a stone's throw
from their protective rocks.

Nothing moves fast
without a good reason

but up here, even a small patch
of grass is worth fighting for.

Deciding whether to use
hard-won energy reserves

can be a matter of life and death.

The arrival of a red fox
means it's decision time.

Up here the air is so starved of oxygen
that a sustained chase is impossible.

The fox has to try and take its prey
by surprise

Not easy in this open country.

The viscachas are rarely more
than a short dash from safety.

Viscachas have thin muscle walls
to their lungs

so they can breathe more freely
at high altitude.

But a rapid escape is exhausting
even for them.

The panic's over for now.

It's time for everyone to
catch their breath.

On the Altiplano
the air is in such short supply

that neither hunter nor hunted
can afford to waste it.

It's at night that the effects of
the high altitude bite hardest.

When the sun goes down

the air's too thin to retain its heat

and the temperature plummets.

For the Andean Hillstar
every night is like a winter.

Even at lower altitudes

hummingbirds save energy at night
by slowing down their metabolism

almost as if they were hibernating.

Up here, that ability can make the
difference between life and death.

Just three hours after sunset
it's already twenty below.

Even running water freezes hard.

This is the moment of truth
for the Hillstar.

Now all it can do is wait.

With the rising sun
the Hillstar comes alive again.

It picked its roosting place
so the very first rays

reach in to warm its chilled body.

This time, it's won through

Every night is a battle to
survive a twelve hour winter.

But the Altiplano also
has a true winter.

For a few weeks each year

its savage climate
becomes even more severe.

For those who can
this is time to leave.

They must search for food in lakes
lower down the mountains.

When the flamingos have gone

the high Altiplano is left
to the elements

and those animals
that have no choice but to sit it out.

The cold can be so severe
that even the salt lakes freeze over.

Any birds that breed late in the season
can be trapped here.

Their young can't yet fly

and their food is now out of reach
locked beneath the ice.

Many of these stragglers will die
frozen into the ice.

Their fate is already sealed.

But some places never freeze.

The Andes' inner fires keep the geysers
and hot springs free of ice.

Here at least, winter will never come.

In this tiny island of warmth
in the most marginal

and extreme of worlds, life hangs on.

The Altiplano may be extreme

but there's somewhere
even more severe.

As you travel south down
the chain of the Andes

winter becomes even harder.

The mountains here may not be
as high as the giants further north

but they're much closer
to the Antarctic.

The snowline creeps lower
and lower

and in the deep south
the ice never melts.

This is Patagonia.

Three huge ice-sheets dominate
the Patagonian Andes.

Covering over seven thousand
square miles

they're the largest expanse of
ice outside the poles

so vast that they generate
their own weather.

Towers of rock rise
from the edge of the ice

the remnants of ancient volcanoes
stripped bare by the glaciers.

Only the condor soars among
these icy peaks.

This is one of the windiest places
on earth.

Chilled air spills
from the edge of the ice-sheet.

Funnelled down the glaciers
and between the peaks

these freezing blasts can reach
a hundred miles an hour.

Almost nothing lives
on the ice-sheet itself.

Surviving even on its edge requires
unimaginable stamina.

The guanaco
a southern cousin of the vicuna.

It's larger
and has a thick woolly coat

and it needs it
to survive the Patagonian winter.

Snow is not the only peril
the guanacos face.

The puma, the lion of the Andes.

This most adaptable of big cats lives
throughout the mountain chain

from the cloud forest to
the high desert

and the snows of Patagonia
but it's secretive and hardly ever seen.

For all the hunters here
winter is a lean season.

They're poorly camouflaged
against the snow.

The grey fox follows the puma to
scavenge any scraps from its kills.

She has hidden stores of food
during the summer.

If she can sniff them out
she'll survive the winter.

The really hard times
last four months.

But slowly the days get longer
and the land comes back to life.

The snowline creeps back up
the mountains.

This is what the condors
have been waiting for.

As the snow retreats
the casualties of winter are revealed

animals killed by cold or starvation
and the remnants of puma kills.

Condors are the vultures of the Andes.

They have superb eyesight.

They can spot food from miles away

and can locate even more
distant carcasses

by watching
for other condors gathering.

The grey fox is a scavenger too.

The winter's survivors
are lean and hungry

and there's stiff competition
for any chance of a meal.

There's a well defined pecking order
at carcasses.

One fox may defer to another

but neither of them can argue
with a condor.

With a three metre wingspan
and weighing up to fifteen kilos

it's the world's largest
flying bird.

The fox simply can't compete.

At this feast the condor is king.

Caracaras have to wait
their turn too

or make do with scraps that fall
from the condors' table.

Spring brings a flood of migrants
to take advantage

of the brief Patagonian summer
like buff-necked ibis.

They waste no time
in starting to breed.

Great grebes over-winter on the coast

but as soon as the lakes
are free of ice

they move inland and start fighting
for territory.

Only the winners will have a good chance
of raising a family

The losers are forced onto lakes higher
in the mountains

where the summer is that much shorter.

Territory is also the key to breeding
for male guanacos.

They gather a group of females
on their patch of ground

and guard them closely
against rival males.

He must always be on watch.

Younger males will seize any opportunity
to raid the harem.

Soon the reedbeds are alive
with nesting birds.

And where there are nests
there are nest thieves.

As soon as eggs are laid
the fox is quick to take advantage.

She's found the nest of
an upland goose.

Now the birds will have to
start all over again.

There's little a bird can do to drive
a fox away from its nest.

But a male guanaco packs
more of a punch.

Soon there will be baby
guanacos to defend

and he's not taking any chances.

Male guanacos are exceedingly territorial
at this time of year

and they won't tolerate intruders
of any kind.

The fox already has a family to feed.

Her cubs will be safer away
from the aggressive guanacos' territory

so she moves them to another den.

There can be as many
as five cubs in a litter.

Their mother has to carry each
individually to the new den

so moving house takes a lot of energy.

Even so, foxes often move
their cubs several times.

The longer a den is occupied

the greater the chance a puma
will find it.

The cubs are still dependent
on their mother's milk

but soon she'll be weaning them
onto solid food.

By the time winter returns
they'll have to look after themselves.

Few of these cubs will live
as long as a year.

If they're to survive
they have a lot to learn

and only a brief summer to learn it.

High summer in Patagonia.

At the edge of
the great ice-sheet

the mountains are almost
clear of snow.

This far south
midsummer days are long

and occasionally it can even be warm.

Patagonia seems almost benign.

The puma hunts mostly at night
but summer nights are short.

There may be more food
at this time of year

but there's less time
for the puma to catch it.

At dusk, a deadly game of cat
and mouse begins.

The guanacos move to the ridge tops.

From there they have a better chance
of spotting a prowling puma.

But under cover of darkness

the odds are stacked
in the big cat's favour.

This time the puma killed
a full grown guanaco

but the most vulnerable are the young.

The cat won't have long to wait
for the new season's baby guanacos.

All the births are concentrated
over just a few days.

That way the puma is spoilt
for choice

and it can't take all the young.

The sooner a new-born
infant can stand

and run, the better its chances
of surviving the summer.

Within days of giving birth
the female guanacos come on heat.

For the males, this will be the payoff
for all the hard work

they've put into defending their harem.

But they can't afford to
relax their guard.

This is when other males are
most tempted to intrude.

First, there's a stand off.

Fighting's dangerous so males

try to intimidate their opponents
by posturing.

But this time
threat has to be backed by physical force.

Guanacos are heavy, powerful animals

and they can inflict a vicious bite.

This 'neck wrestling' is a way
of avoiding being bitten.

The battle over
the winner takes his reward.

So long as he can fend off intruders

the resident male will mate
with all the females in his group

and sire a whole new generation.

This may be midsummer
but at any time

the mountain can spring
a cruel surprise.

On a sunny summer's day

ferocious storms can strike
out of the blue.

From behind its fringing peaks

the ice-cap hurls a frozen blast
down the mountains.

These sudden winds can reach
a hundred miles an hour.

For everything that lives here

these sudden storms are part
of the Patagonian summer.

They can strike almost daily.

Even in the strongest winds
the grebes keep fishing.

All kinds of grebe carry their
young on their back

but here in Patagonia
it's a life saver.

From their earliest days

the chicks feel the brutal
force of the Andes.

But these birds
are great survivors

and if they can make it
through the storms

this is an ideal home.

Sometimes grebes feed feathers
to their chicks.

This may help bind
the fish bones together

so they can be regurgitated safely
as a pellet.

Young of all kinds have to grow fast

if they're to survive
the coming winter.

The young guanacos build up
their stamina

by playing in the last of
the summer sun.

The mother fox has
only a few more weeks

to teach her cubs how to fend
for themselves.

Carrion from a puma kill gives them
their first taste of red meat.

But meat is a luxury.

To survive they will have to eat insects
fruit, leaves, even grass.

They may be playing now

but in a few weeks they'll
be hunting for real

on their own.

Only the most resourceful can
live through an Andean winter.

All along the chain of the Andes

survival depends on adapting to some of
the harshest conditions on the planet

thin air, bitter cold, relentless wind.

But for those that can live here

the mountains provide all their needs.

Our journey of over five thousand
miles ends here

almost in the Antarctic

where the glaciers of Patagonia plunge
towards the Southern Ocean.

The mighty force of the mountains
can give life

but at any moment

it can take it away.

Living in the Andes

is one of the greatest
challenges in the natural world.