They call it America's last frontier.
Half a million square miles of wilderness.
This is Alaska.
Home to some of the hardiest animals on the planet.
Alaskan seasons run fast and furious.
Opportunities are fleeting...
..for people as well as animals.
Survival means making the most of nature's gold rush.
Play it right and you'll hit the jackpot.
Get it wrong and you could lose it all.
It's not about your size.
It's about your attitude.
This land belongs to the bold.
This is Alaska.
Right up on the northern extremes of the planet.
A third lies within the Arctic Circle.
Every season here is intense
but winter is the one that takes your breath away.
For six months, it's a wonderland of snow and ice.
But winter is also a time of bitter cold and desperate hunger.
Up here they call it 'the great white silence'.
It's only September but already in the central mountains,
winter is creeping in.
The peaks of Denali are the highest in North America.
Up there, it's always white.
The lower slopes will soon be buried under meters of snow, too.
This young Arctic ground squirrel is running late.
Too small to face winter head-on, first he has to fatten up.
There's plenty of berries, but not much time.
He needs to nearly double his body weight
and he doesn't seem to be taking the job entirely seriously.
Not only that, now there's a grizzly bear in the way.
She's also building herself up for winter
and she'd make short work of a ground squirrel.
A little piece of shed fur would certainly make his nest warmer.
Is it worth the gamble?
Whether you're a great big bear or a little squirrel,
you have to prepare, and that means taking risks.
That's how it is in Alaska.
If you don't take care of yourself, winter will take care of you.
For a ground squirrel, the way to get through winter is to sleep.
But this will be no ordinary sleep.
For the next eight months, he will be barely alive.
As the air cools,
his body temperature is already slipping towards freezing,
shutting down almost every system in his tiny body.
It's drastic but he really has no choice.
The big chill is coming.
With winter nipping at its heels,
this sandhill crane is high-tailing it south
3,000 miles towards Mexico.
There are some formidable mountains along its flight path.
Their next challenge is to get over the Alaska range
so families join up to make their journey together.
But before they do, they put down in a barley field to rest and refuel.
Some are hardened veterans that have passed this way many times before.
These red-faced adults know better than to linger for long.
Others are complete rookies.
Young chicks making their first flight south.
Birds can sense the smallest changes in air pressure.
There's a storm coming.
Winter has caught them out.
There is nothing they can do
except fuel up and hope the storm blows through.
The younger birds, especially,
don't have the reserves to cope with this for long.
It's starting to seem like a very long way to sunny Mexico.
After two days, the storm starts to ease.
But headwinds keep the birds pinned down.
The grounded flock has caught the attention of a golden eagle.
If the storm strengthens again, they could all perish here.
As the headwinds finally subside, an escape route opens.
The flock rises on the warming air
and makes good their escape before the door closes for good.
Hundreds of thousands of cranes follow this route south every year.
Alaska is more than 1,400 miles from north to south.
Over such rugged, icy terrain,
aeroplanes are pretty much the only way to get around.
It takes a cool head to navigate this kind of landscape.
RADIO: "561 Tango Alpha's 10 north at 5,000 feet
"heading into broad paths.
"Weather's clear."
There's an old bush pilots' saying,
"You can fly for an hour, or you can walk for a week."
RADIO: "Pressure's steady, ten miles of visibility."
This is some of the last true wilderness on the planet.
And the further north you go, the colder and emptier it gets.
One family here can't wait for winter to really arrive.
These polar bears need the sea to freeze completely
so they have a solid platform from which to hunt seals.
Right now, they're hungry.
The cubs' mother can sniff out a meal from 20 miles away.
The rotting remains of a bowhead whale.
SQUAWKING
It may not look too appetising,
but this blubber is packed with calories and vitamins.
An adult bear can eat 60 kilos at a single sitting.
The problem with a feast like this
is that it will bring in hungry bears from miles around.
They might not be a threat,
but she's not going to hang around to find out.
SQUAWKING
Soon the sea will be frozen solid
and the bears will be back in their element.
As the northern end of the Earth tilts further from the sun,
the cold is now stealing across Alaska.
These first strokes of winter give the land the look of a fairytale.
As lakes freeze, the ice cracks and rattles.
RUMBLING
Tradition has it that this is the sound of the water
crying for a blanket of snow to protect it from the cold.
On rare days, when still, cold air
lies on top of a freshly-frozen water, crystals grow,
forming delicate fronds of ice.
These are frost flowers.
And they can bloom and fade in just a few minutes.
By November, river ice can already be half a metre thick.
But in true pioneering style,
Alaskans turn this freeze-up to their advantage.
Come by, come by.
The frozen rivers and lakes become highways into the wilderness.
These Alaskan huskies are built for the cold, and born to run.
They make David Jonas' life just a little easier.
The dogs, they expand my range.
Going on foot is pretty arduous,
but with the dogs, we can go 30 miles a day.
For eight years, he's been living off the land in this lonely valley.
It takes a hardy soul to survive winters like this,
and even hardier dogs.
I use the dogs for getting firewood,
for hauling just about anything from the river up to the cabin.
Water, fish for them, usually.
You're my hardest-working dog!
You want a fish tail?
OK, guys, let's go.
What makes huskies so special is their stamina.
They have a unique metabolism that means they don't tire easily.
They just keep going.
By harnessing this power,
the creeping cold can be kept at arm's length.
They can burn through 10,000 calories a day.
That's three times more than an average man.
So it's extra portions of fish-head soup all round.
There you go.
A little breakfast.
WIND HOWLS
The Alaskan winter is creeping into every corner of the land.
But in the Chilkat River in the far south,
there's something almost magical happening.
On this stretch, warmer water bubbles up from deep underground
and keeps a few miles ice-free all winter long.
There are salmon here.
They've swum for 20 miles upriver to spawn in the open water.
Bald eagles are waiting.
It's the last great feast of the year.
CHITTERING
The native Tlingit people named this river Chilkat for a good reason.
It means, "winter salmon storehouse."
The fishing is very relaxed, while there's a lot to go around.
But then winter really starts to ratchet up the pressure.
WIND HOWLS
Every day, more eagles arrive.
CHITTERING
The mood in the valley changes.
SQUAWKING
The Chilkat becomes the last-chance-saloon
for eagles from across Alaska.
Over 3,000 birds gather in the riverside trees.
For a few weeks, it's the world's biggest gathering of eagles.
One has a badly-deformed bill.
She's not pretty...
..but she's got some serious attitude.
CHITTERING
It comes down to who wants it most.
CHITTERING
SQUAWKING
At minus 30, water freezes almost instantly.
Suddenly, she's dragging around a girdle of ice.
She may have flown a thousand miles to get to this river.
She's not throwing in her hand that easily.
SQUAWKING
No-one got through an Alaskan winter by being feeble.
And winter is going to get a lot worse before it gets any better.
WIND HOWLS
In the southern forests, the trees soften winter's blows.
But there's little protection from the intensifying cold.
A two-metre-tall moose.
Everything about it looks awkward.
That massive nose, those ears,
that hump.
But this huge deer is winter-proof.
Those stilt-like legs keep its body just clear of the snow.
And that long face means that the air it breathes in
gets nicely warmed up before it hits the lungs.
This giant is squeaking by on a diet of twigs and snow.
If ever there was a symbol of Alaskan resilience, this is it.
It's now getting so cold, the ground is frozen solid.
The Arctic ground squirrel's core temperature has dropped
to three degrees below freezing.
His chilled body shows purple on this thermal image.
WIND HOWLS
As winter rages all across Alaska,
ground squirrels are totally oblivious.
FAINT BREATHING
He's only alive because a tiny pilot light
between his shoulders is just ticking over.
Every two or three weeks,
this thermostat kick-starts his internal heating back to life.
He shivers, flooding his body with a life-saving pulse of warm blood,
which briefly reboots and repairs his brain.
After a few hours, the heating switches off again
and his body temperature drops back towards freezing.
An Arctic ground squirrel is only conscious
for about 12 days during the whole winter.
WIND HOWLS
Up in the far north, winter takes a different tack.
It's cold enough to freeze the ocean.
It all starts at two degrees below zero,
when crystals of ice coalesce into a slushy mat.
But the freeze-up can take weeks.
Soon, the bears will be able to use the ice to hunt seals.
WIND HOWLS
As pancakes of ice lock together,
the Arctic Ocean starts to transform.
It's good news for the fox.
He'll follow the bears like a shadow,
ready to pick up any scraps whenever they make a kill.
Until then, he'll amuse himself by teasing the cubs.
New ice is unpredictable stuff.
The youngsters seem perplexed by this strange surface.
Sea ice is bendy
and flexes beneath their feet because of the salt.
At 300 kilograms, Mum knows the sensible thing
is to spread the weight by walking like a cowboy.
But you can't beat gravity.
As the ice thickens,
the cubs get a chance to practise their seal-hunting skills.
They throw themselves at it with all the enthusiasm of youth,
but it will be another year before they'll actually catch anything.
The bears save their energy while the sea freezes around them.
Things are moving fast.
Another 20,000 square miles of Arctic Ocean
turns to ice every day.
Winter now starts to squeeze Alaska hard.
And not just with the cold.
In November, in the far north,
the sun dips below the horizon
and it won't rise again until January.
That's 65 days of night.
The last thing the polar bear family wants
is to blunder into another bear in the darkness.
There are big males out here
that would easily kill one of the cubs.
She won't leave them to fend for themselves
until they're at least two years old.
Further south, the darkness and the cold have less of a stranglehold.
WAVES CRASH
And if you're tough enough,
the Bering Sea is a place to claw something back from winter's grasp.
By midwinter, snow crabs gather in their millions
200 meters down on the seabed.
For Joshua Songstad, captain of the crabbing boat 'Handler'
the stakes couldn't be higher.
When did you set that strength?
INDISTINCT RADIO
'Once you've found that pot of crab,
'you can just follow it to where it goes.
'As long as you stay on top of it, your fishing can be phenomenal.
'It's crazy how good it can be. These pots come up,
'you couldn't stuff another crab in there sometimes.'
Each crab pot weighs 300 kilos
and they must be heaved from the sea
and manhandled around the icy decks day and night.
The cold, the heavy machinery and the storms
all take their toll on the crew.
WAVES CRASH
Being a deckhand on an Alaskan crabbing boat
is still one of the riskiest jobs in the world.
But if they're lucky, the catch can be spectacular.
My main function is to catch crab, keep that block turning,
keep those pots coming and keep the crab coming down.
There's no other reason to be here.
As the deckhands say,
"If the block's not turning, we're not earning."
Once the hold is full of crab, the crew will head for home,
hundreds of thousands of dollars richer.
WAVES CRASH
By December, the nights are at their longest.
Even in the south, there are just
a few hours of murky daylight every day.
Anchorage.
There are only 700,000 people living in Alaska,
and almost half of them live here.
And they have some unlikely neighbours.
A moose has wandered out of the forests,
looking for something tastier than twigs.
MOOSE GRUNTS
He's not the only one.
By midwinter, 1,000 winter-weary moose have arrived,
looking for some comfort.
There are gardens here, and parks,
all full of tasty goodies.
BARKING
And old, frozen pumpkins left over from Halloween.
They may trample the garden and ruin the fairy lights
but the residents are used to it.
Even in town, these moose are on a near-starvation diet,
losing half a kilo of body weight a day.
And winter hasn't finished with any of them yet.
MOOSE GRUNTS
Even though the darkness starts to lift with the new year,
the Alaskan winter is just about to whip up another storm.
Nowhere does it deliver a harder punch
than in the mountains of Alaska's southern coast.
It's here cold air from the frozen interior
meets moist air blowing up from the ocean.
The fall-out from this atmospheric brawl is snow.
Lots of snow.
In some places, more than 20 metres can accumulate through the winter.
If you're unlucky, the ferocious Alaskan winter
will find you and knock you down.
But one animal's fall can be a lifeline for others.
SQUAWKING
Ravens are first on the scene.
The carcass is almost frozen solid.
All they can do is chip off a few icy splinters of meat.
SQUAWKING
It's enough to keep them going until dark,
but they know that tomorrow, they will feast.
HOWLING
In the bitter night, a thermal camera reveals a visitor.
A wolf.
She's powerful enough to break open the frozen carcass.
And by ripping into the meat,
she's doing everyone else a favour, too.
BIRDSONG
SQUAWKING
The carcass is now totally torn open,
and there's still plenty of meat to fight over.
SQUAWKING
If you're clever, you gorge yourself
and then hide a few pieces of flesh in the freezer for later on.
CHITTERING
SQUAWKING
The carcass is too valuable to give up without a fight.
SQUAWKING
The eagle is too hungry to have his feather's ruffled easily.
SQUAWKING
But even the eagle must give way to a coyote.
SQUAWKING
The chance of a free lunch
is dragging all sorts of desperados out of the woods.
A battle-scarred old lynx, blind in one eye.
WIND WHISTLES
Everyone is watching, waiting for any sign of weakness.
SHRIEKING
The coyote leaves with his tail between his legs.
While out in the deeper snows, a little planning can go a long way.
SQUAWKING
There are far worse places than here to be hungry.
WIND HOWLS
The longest, bitterest winter of all is up on Alaska's Arctic coast.
In February, the mercury is dropping to its very lowest.
Perfect for polar bears.
They're out on the sea ice, looking for seals.
And they're not alone.
Polar bears can roam across 100,000 square miles of frozen ocean.
And Arctic foxes will follow them for days
in the hope of some leftovers from a seal kill.
But that only works if the bears you are tracking
find something worth eating.
A piece of old seal skin. That's not going to go very far.
But there's one other place a fox find food.
If it's desperate enough.
To go there means risking everything.
This is Deadhorse.
HORN BLASTS
250 miles north of the Arctic Circle...
..and one of the coldest, remotest settlements on Earth.
Deadhorse only exists because there are huge reserves of oil
to be extracted from below the ice.
It's not the most welcoming place for a tiny arctic fox.
First, he has to get past the local heavies.
Red foxes followed the oil workers here,
and they've made themselves at home.
Twice the size of the arctic fox, he's quite capable
of killing any trespassers on his patch.
But the little fox is hungry enough to take the risk.
Everyone knows you shouldn't put bare flesh on freezing metal.
But the fox has to use his tongue to thaw out the frozen scrap.
It's the kind of place where you have to hold your nerve.
The freezing temperatures don't stop the oil workers
going about their business.
Winter is a good time to get those awkward little jobs out of the way -
like moving a 2,000-ton drilling rig to a new field.
Probably best not to try and push your luck too far.
Just when it seems that warmth will never return...
..there's a sign in the heavens that things are about to improve.
The aurora borealis.
They flare each time a cascade of particles streaming out from the sun
smashes into the Earth's atmosphere.
The aurora puts on its greatest show in March,
just as spring starts to return.
Traditionally, it was believed that these lights were torches,
carried by spirits,
to guide the souls of the lost to a new land of warmth and plenty.
The arctic ground squirrel's central heating has switched back on.
He's pulling back from the brink one more time.
After eight months asleep, he's slowly reenergising,
preparing to face the world again.
Polar bears are still wandering the sea ice, making the most of it
before the spring sun melts it away.
For all Alaska's hardy souls,
winter's supreme test of endurance is nearly over.
The growing strength of the sun has got winter on the run...
..and brings with it the promise of better times.
As the thaw begins, these tough and resourceful characters
have overcome the worst that Alaska can throw at them.
Now they can once again stake their claim on this land.
Of all the challenges of an Alaskan winter,
filming arctic foxes is one of the toughest.
First, you have to get to the Arctic.
Cameraman Toby Strong.
This is the Dalton Highway.
It runs 500 miles north, from Fairbanks
right to the very top of the North American continent to Deadhorse.
That's where we're going to try to film the arctic foxes.
First, we have to get there along this road, which is
one of the most dangerous on the planet, for this reason.
It's ice the whole way. So, yeah, we have to get there first.
The Dalton Highway was built to supply the oil industry
on Alaska's north coast.
Toby, director Tuppence Stone and field assistant Jonathan Fiely
set off for the two-day journey.
It's not one for a nervous driver.
As well as the icy roads, there's also the danger of avalanches.
Before they can cross the highest pass, the crew must wait for the
highway department to clear any potential threat.
BLAST
Fire. Fire!
BLAST
- All clear. - Right, we have to film foxes, I guess. - Back onto foxes now.
250 miles inside the Arctic Circle,
Deadhorse really is at the end of the road.
There's nothing between here and the North Pole
except 1,200 miles of ice.
So this is home for the next two weeks.
Next morning, the cold has intensified.
Ladies and gentlemen,
This morning, the temperature is a balmy -47 degrees Fahrenheit.
And at these temperatures, strange things happen.
Here, we have one glass of boiling water. Watch this.
Isn't that amazing?!
Time to get the thermals on and go fox hunting.
Deadhorse is surprisingly busy.
It's the human presence here on the tundra that's the big
attraction for the foxes.
The foxes have already survived maybe six long months of winter,
and the natural food source up here, which is lemmings,
at this time of year is in a...
It follows a cycle, and at the moment we're in a dip in that cycle.
So foxes are clever, they will find whatever is around,
and if that means coming into town and taking advantage
of opportunities then that is why they are here.
It's time to tap into the local knowledge.
Hi, have you seen any foxes?
- No. - We're trying to film the foxes. - I haven't seen them all winter.
They're everywhere. You know, all of a sudden, they're there.
- You're looking for the white ones? - Yeah.
- Anywhere there's food. - Yeah.
Ten years ago there would have been one walking in front of us
- right now, they were everywhere. - Seriously? - Yeah.
- Have a good day. - Thank you very much. Cheers.
At least there's one consistent piece of advice -
find out where the foxes are feeding.
All these tracks are a good sign.
Weird, isn't it?
Arctic foxes, the sort of totem of the vast wildernesses
of the North, and here we are, sat under a Portakabin.
Not how I imagined...
This cold is such a killer.
It takes several days before the crew finds out
who made the footprints.
It's a fox...but it's the wrong colour.
Red foxes are recent arrivals in Deadhorse.
These pioneering foxes followed the human traffic
up the Dalton Highway, and liked what they found.
They scarcely give the crew a second glance.
This confidence is a worrying development.
We came here to film arctic foxes. So far, we've just seen red foxes.
But, you know, we'll take what we can get at this point.
What'cha gonna do?
As the days pass, there seems to be red foxes lurking around every
corner, but not a single white one.
The bone-chilling cold and 18-hour days starts taking its toll.
There's worrying signs of cabin fever amongst the team.
Working day and night pushes everyone to breaking point.
Just when they are ready to throw in the towel,
the crew gets the call they've been waiting for.
- RADIO: - 'We're just getting a message from the policeman
'to say there's an arctic fox at the back, so we're going to go there.
'Meet us there. Over.'
'He's coming round the back, he's going under the building.'
OK, we'll come in that side, park there and then see how he comes out.
We'll get that side covered. Over.
I have him.
All he's interested in is finding something to eat.
'Stay really calm. He's quite touchy.'
OK, I've got him.
'He is moving off behind the container. I'm going to go ahead.'
The team can barely keep up.
- You go that way. - Yeah!
THEY PANT
- Where is he? - He's climbed up on top of the containers here. - OK.
He leads them on a merry dance through the town.
'Move quickly, I'm going to go to the far side of the building.'
It's hard to run with the heavy camera equipment,
and the cold air is burning your lungs.
Yeah, I'll be a minute.
Oh, my God.
SHE PANTS
Oh, hold it there, hold it there, I see him now.
But the fox is oblivious to the cold.
I'll hang here.
I think he'll move through.
He should be getting some really nice stuff from there.
'What the heck is that fox doing? Licking?'
# Fox in the snow Where do you go
# To find something you could eat?
# Cos the word out on the street is you are starving... #
This is an increasingly rare sight in Deadhorse, so the few hours
spent in the company of such a tenacious little character
are precious.
# Fox in the snow... #
We've been here two weeks, we haven't seen one arctic fox.
The day before we leave,
he allowed us to follow him for the last two hours.
- We were looking at the depths of despair. - Absolutely knackered.
Frozen, but so happy. Absolutely brilliant.
THEY LAUGH
The crew head for home...
..leaving behind those tough enough to deal with the Alaskan winter.