All language subtitles for BBC - Yellowstone 3. Autumn [2009 1080p x264 DTS-1510]

Yellowstone,

volcanic wonderland.

Two million acres of wild space ...

right in the heart of North America.

The heat of the summer has unveiled ...

the full extent
of the Yellowstone wilderness ...

and, for a few precious months,
it has blossomed.

But, now, Yellowstone is changing.

In just a few weeks, the snow
and ice of winter will be back.

As the animals of Yellowstone
now turn to face ...

perhaps the biggest challenges
of their year,

the true value of the world's
first national park ...

is about to become clearer than ever.

It's late August
and on Yellowstone's peaks ...

there is already
a dusting of fresh snow.

Now, a new sound
marks the new season.

Fuelled by testosterone,

the bugle call of this male elk
is a boast of his strength.

All over Yellowstone,

male elk are challenging
each other for dominance.

The sound of Yellowstone's autumn.

They are trying to win
the admiration of females ...

and gather them into a harem.

Only then do they stand a chance
at mating with them before winter.

But the females are not
yet in season,

so they are not really
that interested.

And, for now, they have
a more practical concern.

Winter will soon be here.

They are eager
to head down to lower ground ...

before the snow comes in earnest.

Some will move down
into nearby valleys,

whilst others will
journey much further,

even beyond the boundaries
of Yellowstone itself.

Yellowstone is deep in the
Rocky Mountains of North America,

an isolated high plateau
defended by rugged peaks.

In the middle is the National Park.

The park and the surrounding mountains
form one of the most important ...

and spectacular
wilderness areas on Earth.

In just two months, this great plateau
will become a deep freeze once more.

Before then, the animals of Yellowstone
will have to get ready ...

or get out.

But, for now,
below the snow-dusted peaks,

summer still lingers
in the heart of Yellowstone.

The sun has revitalised this place ...

and, now, there are
more living things here ...

than at any time of the year.

The summer has brought visitors too,

who are enjoying Yellowstone
at its most vibrant.

As the sun now starts
to get lower in the sky,

the rich colours make this ...

one of the best times
to see the geysers.

On the grasslands,
the good times are already over.

These bison are making
the most of the grazing,

but it is now dry and parched.

From now on, they will have to
rely heavily on stored fat ...

to keep them going,

as these meadows become covered
in more than four feet of snow.

Others are already
thinking of leaving.

Pronghorn evolved to outrun a
now-extinct North American cheetah ...

and, so, are the fastest
antelope on Earth.

But, unlike bison, their
lightweight bodies can't store ...

enough energy to keep them here
through the winter.

So, now they must head out.

Their journey
will be the longest of all.

But as many are preparing to get out,
some have no choice but to stay.

In the remote north east
of the Yellowstone wilderness ...

are the Beartooth Mountains.

Here, surviving above 8,000 feet,

a tree now welcomes
the change of season,

the whitebark pine.

All summer, these trees have been
soaking up the energy of the Sun ...

preparing for this moment.

Now, they offer
the animals of Yellowstone ...

a bumper crop of pine cones.

The whitebark pine
is gambling on the fact ...

that animals now need all
the food they can get before winter,

and is hoping it can entice them
to spread its seeds ...

far and wide across Yellowstone.

So, inside the cones, it has
put tasty, nutritious pine nuts.

A pine squirrel.

It snacks on a few of the nuts
to keep going ...

and then buries them, one by one,
in a sheltered hollow beside the tree.

If it hides them well
and packs them carefully,

they should last through the winter.

But this is not
much good for the tree.

Its seeds have gone nowhere.

A grizzly bear mother and cubs.

It's unusual for a grizzly
to have so many cubs.

This mother has found
two orphans and adopted them.

But now she has four cubs
to fatten up ...

before they go into the den
to hibernate this winter.

She's after pine nuts, too.

They are 50% fat.

In a good year, a grizzly bear
can put on five pounds a day ...

eating nuts alone.

If squirrels have done the hard work,

it doesn't matter
that grizzlies can't climb trees.

The squirrel will just
have to start again.

Luckily, this year, the trees
are being particularly generous.

A Clark's Nutcracker.

This is what the tree
has been waiting for.

With its perfectly-shaped beak,
it prises the nuts from the cones ...

and tucks them one by one into
a special pouch under its tongue,

up to 150 at a time,

a fifth of its entire body weight.

Then it flies as much
as 15 miles away ...

and drills the nuts
into the ground in sets of 10,

placing a stone on top of
the stash to mark the site.

It goes back ...

for more ...

and more.

Over the autumn, a single bird
can bury 30,000 nuts ...

across an area of 100 square miles.

When the winter comes,

it will manage to remember the location
of a staggering 70% of these seeds,

even when hidden beneath the snow.

But as the Clark's Nutcracker remembers
its way into surviving the winter,

it becomes
the whitebark's greatest ally.

Although its feat of memory
is extraordinary,

for every 1,000 seeds it buries,
it still forgets 300.

From all those missed seeds carried
far and wide across Yellowstone,

new whitebark pines
will germinate next spring.

It's now September ...

and the elk have made their way
down to graze ...

where the grass on the
river banks is still green ...

and they can browse the nutritious
shoots of young willow trees.

The males are now upping their game.

This bull urinates on himself to
increase his masculine appeal ...

and by thrashing his antlers
to decorate them,

he hopes to make himself
look more impressive.

The females are paying
a little more attention now.

The bull has succeeded
in gathering a fair-sized harem.

But the females are still
not quite ready to mate.

They are now focused
on feeding as much as they can ...

before moving lower still.

But the elk are being watched.

Over the summer, wolves have been less
mobile because of their young pups ...

but their strength is building again.

The elk get twitchy
and head for the cover of trees.

They may be a little safer here ...

but the food in the forest is far less
nutritious than on the river banks.

If they want to eat well
and avoid wolves this winter,

they'll need to keep on moving.

As the elk move gradually downwards,

they follow the rivers
out of Yellowstone's central plateau.

The rivers, in turn,
follow the path of glaciers ...

that flowed from this great bowl
in the last ice age ...

and carved their way right through
the barrier of surrounding mountains.

Today, these valleys
are escape routes ...

for animals from
the returning ice of winter.

Lower down, the valleys
broaden, the rivers slow ...

and a richer variety of trees
grows in the alluvial soils,

the perfect home for Yellowstone's
most industrious creature.

A beaver can fell a cottonwood
tree in just a few hours,

hundreds in a year.

The beaver doesn't chew
through the whole trunk,

just enough to make
the tree unstable.

It then retreats ...

and lets the wind do the rest.

It cuts branches
into more manageable lengths ...

and then swims them down a network of
purpose-built canals towards the dam.

The pond gives this beaver
protection from predators ...

and the canals allow it to forage
far into the forest,

carrying many times
its own weight with ease.

Autumn is the busiest time
of year for beavers.

It won't be so easy to make repairs
when the pond is frozen over.

The sound of running water
is their stimulus ...

to shore up gaps with timber
and plug leaks with mud.

But the dam not only
serves the beavers.

Moose come here
from the forests around ...

to feed on weeds that thrive
in the beaver's shallow pond.

The weed is rich in vital sodium
that the forest can't easily provide.

But now that winter is approaching,

another essential role
for the dam is revealed.

These smaller branches
are not for fixing the dam,

they're for eating.

The beaver secures them
to the mud in the lake bottom.

In just a few weeks,
this lake will be frozen ...

and the beavers won't be able
to cut and move trees.

But they will be able to swim
right under the ice ...

to feed from this underwater larder.

Moose also eat twigs and branches ...

and often try to take advantage
of the beaver's hard labour.

This young male is getting a little
too close to the beaver's larder.

Autumn is not a time for sharing.

It's mid-September.

As the sun drops further in the sky,

the aspens, cottonwoods and maples ...

start shutting down for the winter.

They now digest the green
pigments in their leaves ...

to claw back what nutrients they
can into the trunk and roots.

What's left behind
make the colours of autumn.

Groves of aspen
all turn at the same time.

Each grove descended from one tree,

interconnected by roots,

colour-coordinated.

As cold air sinks further down
from the mountains,

it brings autumn mist
to Yellowstone's valleys.

It was in the autumn of 1870 ...

that the first official
exploration party to Yellowstone ...

began to plan for the creation
of the world's first national park,

the beauty of
Yellowstone's autumn ...

inspiring a complete change
in the way we value the wild.

For the last six weeks
of strutting and herding,

male elk have eaten almost nothing.

They are exhausted.

This bull has done well.

He has successfully held on
to his harem.

And now the females
are finally coming into season.

But they are being distracted
by another male.

If a bull elk can't dominate all rivals,
he can't have access to the females ...

and all his effort
will have been in vain.

Now he must gather
the last of his strength.

The rival wants to take him on.

The aim is to get
an antler point into his neck.

But they are evenly matched.

Neither can penetrate
the other's guard.

Now it's all about power.

A well-aimed thrust
or a broken neck will kill.

This challenger is lucky to get off
with just a parting stab in the rump.

The victor returns to his females.

His young will be born next spring.

But the prospects are not
so good for a defeated bull.

After all this effort,

he will now have to wait until
next autumn to try his luck again.

That's if he even makes it.

Bull elk, exhausted by the rut,

struggle to survive
the Yellowstone winter.

It's now October ...

and the winter is catching up
with the elk once more.

An early flurry of snow is a sign
that it's time to make a decision.

To stay is to face the certainty
of snow and wolves.

To go offers the chance
of an easier life,

but the uncertainty
of the world beyond Yellowstone.

Every autumn, thousands of elk
do leave Yellowstone.

And, as they go,
they cross an invisible line ...

out of the protection
of the National Park.

Here they confront new danger.

Dressed in orange to avoid each other,
but a colour that elk can't see,

hunters come to the forests
just around Yellowstone in October ...

to shoot elk.

Elk, of course, have no understanding
of park boundaries or of Yellowstone.

To them, this is simply an
instinctive migration ...

to find more hospitable land,
so they just keep going.

Beyond the ring of hunting lands,

the natural mosaic
of forest and grass ...

is replaced by an alien geometry.

Circles of irrigated grass,

squares of maize,

golf courses,

the signature patterns of mankind.

It's unlikely they'll be welcome here.

By now,
the pronghorn have pushed further ...

than any of the
Yellowstone's animals.

Out of forests, through farmland ...

and down into the wide prairies ...

at the foot
of the Rocky Mountains themselves.

Their search for winter grazing ...

takes them over 100 miles
to the south of Yellowstone,

the longest migration
of any American mammal.

They have made this journey every
year since the last ice age.

But, nowadays, they have a problem.

Their traditional winter refuges ...

lie right above some of the richest
natural gas deposits in America.

The wells are no direct threat
to pronghorn.

But pronghorn are timid.

At the slightest noise they run ...

and when they run,
they run at 60 miles per hour.

They evolved to avoid cheetahs,
not juggernauts.

Trucks, fences ...

and the disturbance from the wells
have put pronghorn at risk.

There are 1.2 million acres here,

but 75% of it has now been
earmarked for gas and oil.

Back in the farmland,
the elk have found food.

But this grass is
not meant for them.

Ranchers will tolerate elk ...

as long as they don't compete
too much with their cattle.

But, as the elk move in, their old
enemy follows them out of Yellowstone,

an animal that's more difficult
for ranchers to accept.

In their minds,
fear of the wolf runs deep.

Even Yellowstone lost its wolves.

They were wiped out over 80 years ago.

After years of prejudice,
they were reintroduced in 1995,

brought back by the authorities to
restore Yellowstone's natural balance.

But the wolves have done so well,

that now they are moving out of the
park looking for new territories ...

and prey.

Out here, it's clearer to see why
wolves have a bad reputation.

If ranchers' cattle are at risk,
by law, wolves can be shot.

As wolves come back, ranchers are
being forced to return to the old ways,

to get back into the saddle
and protect their herds.

But opinion is changing.

Working with scientists who have
radio-collared the Yellowstone wolves,

ranchers can now keep
track of them ...

and when they know they are near,

shoot not to kill
but to scare them away.

The return of the wolf
will always be controversial.

But evidence is now emerging ...

that wolves are far more important
than anyone imagined,

especially back in
the heart of Yellowstone.

It's nearly the end of October.

The cold autumn nights have brought
a thin crust of ice to a beaver's pond.

Unlike in the river valleys below,

up here, there are not many
tall cottonwood trees.

So this beaver has built his dam
from the shoots of young willows ...

sprouting all along
the side of his pond.

But he is something of a novelty.

Even by the time Yellowstone
was made a national park,

beavers had been virtually hunted
to extinction by fur trappers.

They only began to reappear here
in 1995,

the year the wolves came back.

Now wolves are chasing elk again,
elk have had less time to eat willows,

so willows are sprouting everywhere.

Today, as winter approaches,

all over Yellowstone
beavers are using those willows ...

to put the finishing touches
to a dam-building renaissance.

And for every dam, there is
a new habitat for new life ...

and a richer,
more diverse Yellowstone.

But just as Yellowstone reveals
the complexity of life,

it also exposes its fragility.

On its lofty ridges,

there are signs that all is not
well with the whitebark pine.

From above, it looks like autumn colours
have come to an evergreen world.

But these trees are dying.

Small eruptions of resin
dot the trunk of the tree,

evidence of an invasion.

Tiny beetles are chewing through
the tree's outer defences.

Once inside, they lay eggs that
turn into larvae that eat the tree.

Each tree that is lost ...

threatens all the animals
that rely on its autumn bounty.

The only thing that can stop
the beetles is extreme cold.

But, recently, the climate here
has been getting warmer and warmer.

No national park
can protect against that.

This is a tree
that needs a cold winter.

It's now November ...

and the elk have found
their feeding grounds just in time,

the snows of winter at their heels.

Here they join other herds
who come to this place every year,

where the snow will be less deep
and life a little easier.

But, today, they graze
on an island of grass ...

surrounded by development.

As they run from the winter,

the fate of Yellowstone's animals
outside the national park ...

is decided not by the cold,
but by people.

These elk are lucky.

This refuge has been kept aside to
give them some degree of sanctuary.

So, although the park isn't big enough
to protect all its animals all the time,

its influence can spread
beyond its boundaries ...

and if even ranchers
can come to tolerate wolves,

then anything is possible.

In the mountains of Yellowstone,

where the elks' bugles signalled the
beginning of autumn just two months ago,

all seems deserted.

But, now, the final act of the season
is about to take place.

From out of apparently nowhere,
come the bighorn sheep.

The toughest
of all Yellowstone's animals,

they can stay here all winter ...

on slopes and crags that the
biting wind keeps clear of snow.

Now they are coming together to rut.

Like elk, the males
battle for females.

But where elk do their best
to avoid fights,

bighorn relish them.

A quick test of horn size and of
other important bits of anatomy,

and the males get straight to the point
of sorting out who is toughest.

As the sound of their battles echoes
across the Yellowstone wilderness,

it marks the end of autumn.

Now the great change
is coming again.

Winter is here.

As the snow returns to Yellowstone,
it seems like the clock is turning back.

All traces of the human world
are covered up.

A reminder that when the heart
of this great wilderness ...

was made a national park,
nearly 140 years ago,

it was one of the most
remote places on Earth.

But as the human world
has crept up on Yellowstone,

the true value of this remarkable
space has become ever clearer.

Though, in many ways, Yellowstone
is not big enough,

its influence reaches
far beyond its boundaries.

Not just to the land around,

but wherever there is a wilderness
preserved for its own sake.

Here, in the heart of America,

the first national park was born.

An idea that has led the way ...

in redefining our relationship
with the wild all over the world.

Some say America's best idea.