-Europe... a continent renowned for its spectacular cities and civilizations.

But this is a surprisingly wild land, with over 10 million square kilometers of diverse natural habitat, stretching from the northernmost reaches of the Arctic... to the crystal clear waters of the Mediterranean Sea.

And across this extraordinary continent, an epic transformation is under way as the wild heart of Europe is unleashed once more.

♪♪ People are supporting the natural world.

-Let's go to the nest and see how the chick is.

-Species are being reintroduced.

-It's not sleeping very well, so we have to be really fast.

-And nature itself is bouncing back.

[ Bellowing ] The circle of life is being reforged as the wild returns to Europe.

♪♪ But in the northernmost region, extreme conditions mean a constant battle for survival.

And to protect one species' ancient migratory route, people and wildlife must work together to regain their grip on the land of snow and ice.

♪♪ ♪♪ -Lapland... a vast... isolated... and unforgiving land.

Located in the extreme north of Europe, much of this iconic landscape lies within the Arctic Circle, spanning Norway, Sweden, Finland and Russia.

♪♪ As winter begins to loosen its grip, sunlight returns to Lapland after a month of near-darkness.

♪♪ But for the animals that brave the cold, adapting to the conditions is key.

♪♪ Yet one creature thrives in these Arctic conditions.

Equipped with exceptional hearing, a snow-covered landscape is perfect for this finely tuned hunter.

The hawk owl uses the muted silence of the snowy forest to its advantage.

♪♪ ♪♪ Lemmings remain active through winter, burrowing underneath the snow to find food.

But this hungry rodent cannot avoid the detection of the hawk owl's super senses.

As the lemming rummages... the hawk owl locks in on the sound.

Its ears are so finely tuned that they can detect prey under a foot of snow.

And specialized feathers make for an almost silent approach.

The strike is precise and lethal.

Owls aren't the only creatures that have toughed it out here all winter.

♪♪ And one is a true icon of Arctic survival.

♪♪ Built for the cold, this reindeer forages for food beneath the snow.

A dense woolly undercoat keeps the reindeer warm, while hollow hairs in the outer layer trap the heat, providing them with excellent insulation.

They may be perfectly adapted to the Arctic conditions, but with so many mouths to feed, not all survive these winter months.

And in the Arctic food chain, a reindeer carcass provides a lifeline for Lapland scavengers.

Like the wolverine.

In winter, most wolverines survive by hunting or scavenging reindeer, which they locate with their powerful sense of smell.

A fat-rich reindeer carcass is a feast for this stocky carnivore.

But they won't eat it all in one go.

By carrying off and burying chunks of the carcass, this lucky find could sustain him for months.

In the meantime, Lapland's other scavengers make use of the leftovers... day and night.

♪♪ Even bears get in on the action.

Despite the Arctic landscape, more than 3,000 brown bears thrive here.

For the massive mammals, a reindeer carcass is a calorie bonanza and the perfect midnight snack.

[ Bird squawks ] But this seemingly idyllic habitat is under threat.

♪♪ Much of Lapland's wilderness has been altered.

♪♪ In its mountains, rivers... and old-growth forests.

♪♪ ...pristine habitat has been lost.

♪♪ A demand for natural resources has disrupted many natural systems.

♪♪ And Lapland's most iconic animals have been pushed to the edge of extinction... including the mysterious Arctic fox.

♪♪ Its brilliant white fur made it a target for hunters.

By the 20th century, an Arctic fox's hide was worth as much as a year's wages in Scandinavia.

♪♪ As a result of hunting, the fox population plummeted to as few as 50 individuals.

But today, there's hope for Europe's Arctic fox.

♪♪ The Norwegian Arctic Fox Breeding Programme is bringing the animals back from the brink.

Today three litters of the critically endangered foxes are being prepared for release into the wild.

For the mission to succeed, the team have a narrow window of opportunity.

And at nine months old, these juveniles are now at the critical age.

Releasing them at the end of winter gives the foxes the best chance of survival.

Each of the 19 foxes must be packed onto sleds... and secured.

In this terrain, stress and injury are very real threats.

But as they prepare to set off for the release site, high in the Norwegian mountains, bad weather sets in.

A sudden blizzard whips up the snow, limiting visibility and slowing down the mission.

♪♪ Kilometers from the mountains, the release may have to be aborted.

♪♪ ♪♪ Just halfway to the release site, with the weather showing no sign of letting up, the team stops to make a critical decision about the fate of the foxes.

♪♪ The extreme weather could leave the team stranded on the mountain for days.

♪♪ But returning to base would mean missing this golden opportunity to release the foxes when their chances of survival are at the highest.

Wind chill is making it feel like minus 20 degrees Celsius, as well as whipping up near white-out conditions.

♪♪ Despite the extreme weather, the team decide to push on through the wind and snow.

♪♪ ♪♪ ♪♪ Against the odds, they arrive at the release site with a few hours of daylight to spare.

This artificial den is the foxes' temporary home until they're ready to strike out on their own.

♪♪ One by one, the pups are released into the shelter.

♪♪ ♪♪ Siblings are kept together to minimize the stress of the release.

[ Pups squeaking ] ♪♪ ♪♪ The pups are left to adjust and acclimatize before the den is reopened and the foxes are finally free.

♪♪ It doesn't take long for one pup to get a taste of freedom.

♪♪ Temperatures are below minus 20 degrees Celsius, but with the warmest pelt of any Arctic species the pups don't seem to mind.

♪♪ ♪♪ Thanks to the dedication of the Norwegian Breeding Programme and continued conservation in Sweden, there are now 300 Arctic foxes in the wild, six times the number that once existed.

These pups will spend the rest of the winter together before striking out alone to extend the blood lines of one of Europe's rarest species.

♪♪ [ Pups yipping ] ♪♪ As spring finally awakens, Lapland begins to heat up.

♪♪ ♪♪ The warming rays of the sun soon transform the wintry landscape and beckon a new chapter for one of its most famous residents.

♪♪ Reindeer seek refuge in the forest during the long winter.

Trees offer shelter from the elements and limit the buildup of snow, allowing the animals to dig out and eat the vegetation beneath.

♪♪ But the onset of spring signals the start of one of Earth's great migrations.

♪♪ Having toughed out the winter months in the forest, the herd will now travel hundreds of kilometers north towards the Scandinavian Mountains.

to arrive in time for summer, where fresh vegetation will help them restock their fat reserves.

The migration will be exhausting and dangerous, and there will be little food along the way.

♪♪ Fortunately, the reindeer have an ancient alliance.

♪♪ [ Indistinct conversations ] The Sami.

♪♪ They are northern Europe's last indigenous people, occupying the region they call Sapmi.

As reindeer herders, they use every part of their animals for food and clothing.

♪♪ Tied to the herd's annual migration, the Sami may have adopted some modern machinery, but they also rely on their ancestral knowledge to master Lapland's harsh conditions.

♪♪ They can read the landscape and their reindeer, keeping them safe from predators.

♪♪ Now that climate change and human activity is affecting the reindeers' migrational route, it's often down to the herders to decide the best time to commence the journey.

♪♪ For this herd of over 1000 reindeer, conditions in the forest and beyond must be just right before they set out.

The success of the migration depends on it.

More than half of the herd is pregnant and due to calf in the next month.

Their destination in the mountains will provide the females with the perfect birthing grounds and plenty of nutrient-rich food.

But herder Leif-Anders Blind must wait for the right conditions to start the journey.

While they remain in the forest, the herd must be kept in check.

Today the Sami take advantage of modern technology, like GPS... and snowmobiles to corral their reindeer.

♪♪ But they are still reliant on man's best friend.

♪♪ Four-year-old Jaygo was born and bred for the job.

-[ Whistles ] ♪♪ -His innate herding nature makes him the perfect Sami companion.

♪♪ ♪♪ Having started working with reindeer at just a year old, Jaygo is now at one with the herd.

♪♪ Working in tandem, the man and dog team guide their reindeer... ...to the best feeding grounds in the thawing forest.

♪♪ Together Leif and Jaygo make sure that the herd is at a constant state of readiness.

[ Indistinct conversations ] For the time being, all they can do is wait and hope for conditions to change.

♪♪ ♪♪ Finally the early spring sunshine has begun to melt the top layer of snow.

And overnight it has refrozen into a hard crust.

An easy surface for migrating reindeer and one that won't sap their energy.

♪♪ Now is the time to get the migration under way.

But shifting the massive herd is no easy task.

♪♪ It takes manpower, supplies, snowmobiles... -[ Whistles ] -...and of course, man's best friend.

The migration will take the Sami and the reindeer a grueling 240 kilometers from their winter grounds in Ektrask to summer pastures high in the Scandinavian Mountains.

Traveling through dense forests is slow going, so the Sami guide their reindeer onto a natural roadway... of ice.

A network of frozen rivers and lakes connects much of the migration route, making it easy for reindeer to cover ground quickly.

♪♪ ♪♪ Their hairy hooves give the reindeer a good grip on the ice.

But still, covering 16 kilometers a day is a huge effort for pregnant reindeer.

♪♪ After a day of trekking the frozen river, the herd are desperate for food.

Before night falls, Leif-Anders guides his reindeer to a sheltered area where they can feed and rest.

♪♪ With spring only just awakening, there's little food.

But reindeer are specialists in winter foraging.

Under the snow and on the trees, there's a feast to be had.

Lichen.

Consisting of more than 80% carbohydrates, very few species can digest it.

But the reindeer's gut contains a large fermentation chamber, housing billions of bacteria which secrete special enzymes that can break down the lichen.

♪♪ Also known as reindeer moss, it is one of the few food sources reindeer rely on.

♪♪ ♪♪ With millions of hectares of forest in Lapland, this food should be everywhere.

But Lapland's trees have been vanishing, and the lichen that supports the reindeers' migration has also been wiped out.

Lapland has been ravaged by the logging industry.

♪♪ Since the timber boom of the 19th century, much of the region's woodlands have been harvested.

♪♪ It's had a huge impact on the ecosystem.

♪♪ ♪♪ And the lichen.

-[ Speaking native language ] -Even in the best conditions, lichen grows at just 5 millimeters each year.

A lack of food is one of the main reasons that global reindeer numbers have halved in the last two decades.

Losing a key species would impact the entire ecosystem.

♪♪ ♪♪ But there is hope in Lapland.

On the migratory route of the remaining reindeer, an organization called Rewilding Sweden is on a mission to help nature and the Sami herders around a World Heritage Site called Laponia.

In this area of forest, mountains and wetlands, logging is totally forbidden.

Now Rewilding Sweden is planning to get this pristine region expanded to protect the surrounding habitats.

♪♪ This expansion of the World Heritage Site will also protect the reindeers' precious lichen supplies... and will give a boost to a natural network.

Trees may seem like solitary plants, but they are in constant communication through what is called the "woodwide web."

Beneath the surface, a web of fungi and bacteria are plugged into the tree's roots.

Trees provide the fungi with sugars and in return receive vital nutrients.

This complex network even allows trees to share resources between each other.

♪♪ Old-growth trees act like hubs, sending excess carbon and other goodies to seedlings and any struggling neighbors, helping the whole forest thrive.

But clear-cut logging, especially in old-growth forests, is destroying this natural network.

Without older hub trees available to support younger trees, even unlogged forest is degraded.

So the more old-growth forests are protected, the stronger the woodwide web will be.

♪♪ While the forest and lichen recovers, Leif-Anders must use artificial feed to keep his pregnant reindeer fed.

It's expensive for the Sami, but it's the only way the herd will make it to their birthing grounds.

♪♪ Over the years, the road to the mountains has become increasingly tough.

♪♪ As a result, this traditional form of reindeer husbandry is becoming a lost art.

♪♪ ♪♪ Only 10% of the Sami population are sticking to the ancient herding way of life.

♪♪ Modern methods are effective, but keeping the migration on track in such an extreme environment is not without its added costs.

♪♪ And now that there are less natural lichen grazing sites, food bills have dramatically increased.

♪♪ Many can no longer make a living from reindeer husbandry.

♪♪ ♪♪ But for those that do, getting their precious herd to the mountains means everything.

With full bellies, the herd are ready for another day of traveling.

♪♪ ♪♪ ♪♪ ♪♪ Following Leif-Ander's lead, the herd head towards the frozen river.

♪♪ ♪♪ However, each step they take is being watched by a supreme hunter.

The Eurasian lynx is more than capable of taking down a full-grown reindeer.

♪♪ Solitary by nature, the silent hunter will take up to four of the fat rich mammals in a single month.

♪♪ Fortunately for the reindeer, their Sami guardians are close by.

The lynx will not attack while they remain with the herd.

But the herd faces greater dangers from climate change.

♪♪ ♪♪ In early spring, Lapland's rivers usually remain frozen.

Yet with each passing day, the warmer spring temperatures thaw the icy pathway.

♪♪ ♪♪ The Sami have been using frozen rivers as a reindeer walkway for thousands of years.

♪♪ ♪♪ However, many of these waterways have been impacted by man, making them extremely dangerous.

At the turn of the 19th century, the timber industry in Sweden boomed.

Before, there had been a minimal human impact on the country's woodland.

But soon, almost all forests were encompassed by the growing timber demands of industrialized Europe.

Rivers were altered by logging companies to support the transportation of logs, making them narrower, straighter and faster flowing.

♪♪ Now modern-day threats to rivers come in the form of hydroelectricity.

♪♪ Both industries have distorted Lapland's rivers... ♪♪ ...making layers of ice unstable.

♪♪ Walking reindeer across the dangerous surface of these altered rivers is simply too risky.

♪♪ Only three main rivers in Lapland remain suitable for reindeer.

Leif-Anders and his herd migrate across the free-flowing Vindel River.

♪♪ Even here, life on the ice requires detailed planning.

♪♪ ♪♪ Leif-Anders may have a deep understanding of the river, but running into a dangerous crack in the ice is inevitable.

Finding a way around would add days to the migration.

The herd must face this challenge head on.

With many of the reindeer so close to giving birth, Leif must get them to the mountains in the next few days.

But he can't force his herd to take the plunge.

♪♪ He needs one of his prized reindeer to take the initiative.

♪♪ Once one brave leader plunges into the icy waters, the rest follow.

♪♪ Thanks to their air-filled fur, the reindeer are relatively buoyant and their coats repel water, keeping them dry.

♪♪ ♪♪ [ Dog barking ] The Sami and their reindeer are not the only ones that rely on the rivers.

Lapland also hosts an epic aquatic migration.

Far in the Atlantic and Baltic Sea, salmon undertake a long journey into the freshwater rivers to spawn their next generation.

To help the migrating salmon, Sweden's Reborn Project is working to restore the region's important waterways.

♪♪ In the past, logging companies removed rocks from Sweden's rivers, increasing the current and making it easier to float logs.

♪♪ Now the Reborn team are putting boulders back into the great waterways, stemming the flow and creating a more natural river.

-Nature, it's really forgiving, actually, if you just want to give it a helping hand.

♪♪ When you are able to set the natural processes, nature will take over and fill in all the gaps.

♪♪ -Teams are working around the clock to re-wild over 190 kilometers of river, with more than 2,000 spawning grounds being prepared for the ocean visitors.

The journey that awaits Lapland's waiting salmon is one of nature's most intense feats of endurance.

On land, reindeer across the region are reaching the final leg of the migration.

Sami herder Leif-Anders has followed his massive herd to the edge of their birthing grounds.

The females are all just days away from giving birth, so the herd must get back on the road to complete the final leg of the journey.

♪♪ The reindeers' innate migratory instinct gets things moving at first light.

♪♪ ♪♪ But not everyone is in sync with the migration.

♪♪ ♪♪ The reindeer aim to give birth at the end of the migration, but sometimes a calf arrives too soon.

♪♪ Born just a few days too early, this calf has been abandoned.

Its mother's instinct to continue the migration was just too great.

♪♪ Surviving on its own in the wild would be almost impossible.

Fortunately the newborn reindeer is given a second chance.

The calf needs its mother's fat-rich milk to survive, but with no idea who its mother is, this abandoned newborn will need to be hand-reared.

♪♪ ♪♪ Without its mother, the tiny reindeer will never be part of the herd.

But now it has an adopted home.

It can live a happy life.

For the rest of the herd, their journey is almost complete.

Leif-Ander's reindeer arrive in the foothills of the Scandinavian Mountains.

♪♪ For a brief moment, the herd must clash with the modern world.

♪♪ This final leg of the migration requires a short stint on a man-made road.

♪♪ ♪♪ ♪♪ ♪♪ ♪♪ The herd soon returns to the forest.

♪♪ From here, the weary migrators will walk the final kilometers to their summer grounds, unaccompanied by the Sami.

♪♪ ♪♪ ♪♪ As the herd close in on their destination, trees give way to mountains.

♪♪ This new landscape heralds the end of the grueling migration... ♪♪ ...and the beginning of new life.

♪♪ To have safety in numbers, reindeer synchronize their birthing, with 80% of the pregnant females set to have their calves within the next week.

♪♪ ♪♪ As the snow melts, it reveals what the reindeer traveled here for.

♪♪ A mountainside feast.

♪♪ ♪♪ ♪♪ Far away from the feeding reindeer, Lapland plays host to an even bigger migration, which faces its own unique challenges.

♪♪ ♪♪ Baltic and Atlantic salmon begin a mass exodus from the sea as summer commences.

After a few years feeding in the expansive Atlantic Ocean, the fish must return to their freshwater origins.

♪♪ Their homing instinct is so strong that the migrators can navigate thousands of kilometers from the open ocean... ♪♪ ...to the exact stream of their own birth.

♪♪ ♪♪ ♪♪ The salmon's epic migration is also a lifeline to other species, with many preparing to greet the ocean visitors, especially those that can feed on the fish's precious eggs.

Back on solid land, another one of Lapland's wild migrations is coming to an end.

The reindeer are already reaping the rewards of their long migration.

Melting snow reveals a banquet of lichen and grass, with yet more nutritious vegetation to come in the summer months ahead.

For some, the completion of their migration has triggered the most precious of moments.

As females take themselves away from the main herd, it means only one thing -- they are ready to give birth.

♪♪ A single calf is a mother's reward for the arduous journey to the mountains.

♪♪ It only takes the newborn a few moments to get to its feet.

♪♪ ♪♪ Life on the go starts early for reindeer.

The calf's first few steps are shaky.

But after just a few hours, a newborn reindeer is capable of out-running a human.

♪♪ ♪♪ The new mothers and calves are not alone on the mountain.

Around half of the herd have given birth on the same day.

♪♪ ♪♪ This unique synchronization ensures more calves survive.

For the reindeer, safety comes in numbers.

Lapland's rivers are also the final leg of an epic migration for Europe's salmon run.

After one to five years maturing in the seas and oceans, salmon enter rivers with one single purpose.

♪♪ To spawn the next generation.

♪♪ Even in the most pristine of waterways, the upstream journey is brutal.

Their entire life in the ocean has been in preparation for this energy-sapping journey.

Such is their dedication to the cause, salmon cease eating during their upstream battle.

All their energy is reserved for the largest of obstacles.

♪♪ With extreme power and endurance, salmon take to the air to overcome steep climbs.

♪♪ ♪♪ Before the salmon arrive, conservation and rewilding teams have been hard at work creating the spawning beds for the weary salmon.

Fierce currents of rivers deformed by logging and hydropower have washed away many of the stone beds that salmon need to lay their eggs in.

So teams meticulously place gravel into the river, with the goal of creating more than 2,000 new spawning sites for the salmon to lay their eggs.

♪♪ ♪♪ All of the hard work gives the salmon the perfect habitat to spawn thousands of eggs.

After years in the ocean, the weary fish have now spent months in the freshwater environment for this one moment.

♪♪ This mass spawning is exactly what many of Lapland's wild residents have been waiting for.

♪♪ Dippers use specially adapted wing muscles to fly underwater to grab the nutritious eggs.

Goosanders also make diving sorties for the annual gifts.

♪♪ But with each female salmon laying thousands of eggs, many will survive.

With nothing but their nutritious yolk sac for food, the developing salmon take months to finally reach the moment of truth.

♪♪ Their chance of surviving in the wild is small, but with rewilding breathing life back into their home, they now have a fighting chance.

-To bring back the life to the river, you can really see the huge effect of what's coming.

We have done something good for the future.

-The two very different migrations of the reindeer and salmon have come to represent the success and challenges rewilding faces in Europe's northernmost point.

♪♪ Continued rewilding work will protect the migrational corridors of both species, as well as many others.

Now the future of Lapland's wild heart lives on in the next generation, growing in Europe's new wild.

♪♪ ♪♪ ♪♪ ♪♪ -To order "Europe's New Wild" on DVD, visit ShopPBS or call 1-800-PLAY-PBS.

Also available on Amazon Prime Video.

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