♪♪ [ Suspenseful music plays, birds chirping ] ♪♪ -Imagine a tree could tell a tale.

Imagine you could peel back the layers of time... ...to see the amazing events that have played out around these ancient branches.

♪♪ This is the story of a special Scots pine.

[ Squeak ] [ Tender tune plays ] For 500 years, it's stood firm here in Scotland's Wildheart... ...growing steadily alongside generations of animals and people.

This is the story of Wildheart.

♪♪ ♪♪ ♪♪ ♪♪ ♪♪ -Ancient, weather-worn, and gnarled, our Scots pine grows here, near the heart of the Highlands.

For a tree of this species to live for five centuries is rare, but Wildheart has stood guard here on the edge of the forest for all those years.

♪♪ Few living things spend longer on Earth than a tree and Wildheart has stood steady here as many generations of animals and people have come and gone.

♪♪ Living through drought and deluge, a testament of the ages is written beneath the scales of its bark.

And what a tale it has to tell.

Of the battles that nature has fought against the rising tide of humanity and how the wild world has hung on in the face of so much pressure.

[ Cheeps ] ♪♪ [ Thunder rumbles ] ♪♪ Scots pines started spreading across these mountains at the end of the great Ice Age, when vast herds of reindeer roamed the high tops and wolves still stalked the glens.

[ Birds chirping ] But Wildheart's story begins on a cool misty morning in the middle of the 16th century.

♪♪ ♪♪ With seven billion fewer people walking the Earth, nature still rules the planet in these far-off days.

♪♪ The great wood that the Romans named the Caledonian Forest still covers vast tracts of the Highlands.

It's full of mysterious creatures.

[ Suspenseful music plays ] [ Popping ] ♪♪ [ Rasping ] ♪♪ ♪♪ Capercaillie.

A bird that has an intimate relationship with the Scots pine.

They live here, breed here, and even feed on the tree's needles, when other fruits and berries wither away.

♪♪ Common and widespread in Scotland, their stronghold is here, in the vast pine forest.

[ Rasping ] The male bird's bizarre popping call is summoning the females to the lek.

[ Popping ] [ Popping ] [ Popping ] Here, in a forest clearing, they'll compete for the right to mate exclusively with all the hen capercaillies.

[ Pop ] [ Pop ] Weighing in at nine pounds, this young bird is in superb condition.

[ Popping ] [ Rasping ] [ Popping ] But an older male is up for the fight, too.

[ Pop ] [ Pop ] [ Popping ] [ Rasping ] ♪♪ ♪♪ ♪♪ [ Rasping ] [ Popping ] [ Popping ] It's time to do battle.

[ Rasping ] ♪♪ ♪♪ They're evenly matched.

It's simply a question of who gives way first.

♪♪ The younger male is on the run, handing victory to the dominant older bird.

♪♪ Monarch of the glen, he's retained mastery of the lek.

All the females are his.

[ Capercaillie calling ] As the sun rises, other voices ring out across the clearing.

This is Mary, Queen of Scotland.

[ Mary giggling ] Crowned at just nine months old, she's at the heart of a dynastic dispute as ferocious as the one between the capercaillies.

A pawn in a diplomatic game, the child is promised as a wife to the son of King Henry VIII of England.

[ Mary giggles ] But the Scots have grown cold on the treaty, and the child has been hidden away here in the care of her maid.

♪♪ Innocent and happy games are a stark contrast to the turmoil that lies ahead for Mary.

♪♪ In her play, a cone is cast away.

[ Mary giggles ] It's landed in the perfect spot, clear of the other trees at the forest's edge.

♪♪ ♪♪ Two years on, and the seed from Mary's cone has become a tiny tree.

♪♪ The capercaillie lek has a new master now.

♪♪ And the young queen has been sent away to France as the child consort of the king's son.

♪♪ Mary's tree looks like a survivor.

Its name is Wildheart, a brave pioneer seemingly marching forward across the moor.

♪♪ The open space has given it a head start, and it's already avoided being devoured by hungry red deer, mortal foes to Scots pine saplings.

Wildheart's animal neighbors are getting busy.

The spring of 1549 looks like a fine one.

And it's time to search for homes and mates.

The red squirrel is one of the Caledonian Forest's most dashing residents.

The aerial world here is full of spaces to find food, seek out mates, and get the next generation on its way.

Red squirrels spend nearly 90% of their lives in the treetops, and they're superbly adapted to climb and leap.

With double-jointed ankles and small, sharp claws, they can get up and down trees fast.

[ Bird calling ] Early spring is a special time for red squirrels.

Already pregnant with kittens, this female is looking for a comfortable nest site, away from predators.

But this one is already taken.

She'll need to keep searching.

Three months on, and Wildheart is still holding fast.

A good inch has been added to each springy branch.

The next few years will be make-or-break for the tree.

A Scots pine can add a foot in height every year.

♪♪ But it's not safe from the hungry deer quite yet.

♪♪ The squirrel has been successful, too.

There are kits in the nest.

Near Wildheart's slim trunk is a bank of spongy moss -- an ideal liner for the squirrel's drey.

♪♪ It's just rather a challenge to hold onto it all while you transport it to the very top of a pine tree.

♪♪ A fastidiously clean animal, the red squirrel mother goes through this routine every couple of days.

♪♪ ♪♪ ♪♪ And she'll be stuck with it for a while.

It'll be another couple of weeks before the kittens can emerge from the drey.

♪♪ [ Thunder rumbles ] As the 17th century begins, the crowns of England and Scotland have united.

Mary's son James now rules both kingdoms, but the relationship remains unpredictable.

♪♪ At 50 years old and 20 feet high, Wildheart has now survived many seasons of the fickle Highland climate, and the tree is now surrounded by a crowd of neighbors.

♪♪ In the Highlands, temperatures may drop below freezing even in late spring.

♪♪ And snow can fall in any month of the year.

♪♪ As the years roll by, each generation of Wildheart's neighbors take their chances against this background of ever-changing weather.

♪♪ ♪♪ Crested tits may be small, but they're the toughest of all the birds living in Wildheart's neighborhood.

[ Bird calling ] ♪♪ ♪♪ A true specialist, crested tits only live in this forest.

♪♪ Even in the 17th century, they're not found anywhere else in the British Isles.

The harshest of winters can't deter crested tits.

♪♪ Like the red squirrel, they're able to seek out caches of food beneath the soft snow, seeds shed from Wildheart's cones that will never grow and thrive.

♪♪ ♪♪ Wildheart continues to flourish.

A Scots pine can thrive no matter how fickle the climate, changing shape and angle as the years pass.

As 1650 draws to a close, our tree is more than 100 years old... and 80 feet high.

♪♪ Maturity brings a wider trunk, and the bark is thickening, branches spread, and the pine needles are safely out of reach of the grazing deer.

♪♪ This tree produces both male and female flowers, which means it can pollinate itself, creating the seed-rich cones which will keep the forest alive.

♪♪ As long they don't fall victim to yet another generation of hungry red squirrels.

♪♪ ♪♪ ♪♪ [ Thunder rumbling ] The end of the 17th century brings political turbulence.

Civil war racks the British Isles, and English lords have replaced Mary's great-grandson James II with Dutch-born William of Orange.

But in the Highlands, there are some who still fight to restore a Scots king.

♪♪ The Jacobites.

♪♪ These two, Donald MacGregor and his son Rob Roy, know the Caledonian Forest intimately.

♪♪ Using guerrilla tactics, it's easy for Highlanders to outwit the English Redcoats.

Especially when the enemy soldier is lost and alone.

♪♪ ♪♪ [ Donald grunts ] [ Soldier grunts ] A quick victory.

But Rob's future won't be so easy.

Forced into the life of an outlaw, he'll live on the edges of society till the end of his days.

But the Caledonian Forest will always be his home.

His knowledge of this living place and its bubbling waterways will keep him safe.

The Dee is one of Scotland's longest arterial rivers, an important thoroughfare for Highlanders both human and animal alike.

The river is an important partner for the forest.

Each keeps the other healthy.

Water replenishes and nourishes the trees, but the forest feeds the river with nutrients from fallen leaves and branches.

On a tributary downstream, a special pair of Highland birds are busy servicing their nest beneath a waterfall.

They're dippers -- true specialists here.

The only aquatic songbird in the world, they're able to dive beneath the surface to harvest insect larvae and tiny fish for their well-grown young.

But like the Highlanders, they live a precarious life.

[ Thunder rumbling ] The brood of chicks is ready to fledge, but an unseasonal downpour is transforming the benign river into a raging torrent.

♪♪ ♪♪ The parents need to coax the chicks out of the nest as quickly as possible.

♪♪ ♪♪ ♪♪ ♪♪ Delaying their fledging even by a few minutes could see the youngsters swept away by the torrent.

♪♪ ♪♪ The chicks need to leave the nest now, but they've never flown before and have to navigate the slippery rocks while avoiding the raging river.

♪♪ The parents offer tasty morsels to draw them out of the nest.

♪♪ ♪♪ The winds whip through Wildheart's forest.

♪♪ Lives are at risk across the Highlands.

♪♪ ♪♪ The river still rises.

♪♪ ♪♪ ♪♪ ♪♪ But the dipper chicks are all out and safe.

[ Birds calling ] The unseasonal storm has swept across the whole forest, and several of Wildheart's neighbors have been felled by the wind.

Suddenly there is space around Wildheart once more.

Fallen trees and branches are also a valuable home for some.

Meet the timberman.

Scotland's longest beetle.

♪♪ He's just emerged into the spring sunlight after spending four years in his larval stage beneath the surface of Wildheart's scaly bark.

♪♪ The spectacular antennae will help him locate a mate.

And he needs to do it quickly.

His adult lifespan will be only a third of the time he spent beneath the bark as a grub.

♪♪ Four feet beneath him, the forest floor is dominated by a fortress.

A fortress built by ants.

These mounds grow across generations, and this one was already established when Mary cast her cone away and Wildheart's journey began.

Wood ants are a keystone species here, traveling through all three dimensions of the forest to capture insects which are moved back to the mound to nurture the colony.

Wood ants also farm aphids high in the pines' branches.

A gentle stroke from a farmer ant produces sticky and nourishing honeydew.

And in return for the sugary milk, the aphids buy protection from their wood ant guards.

As the fallen trees decay and collapse, they provide dens for Wildheart's predator neighbors.

Pine martens are one of the forest's most efficient predators.

Now at the beginning of the 18th century, their population is thousands strong.

Wherever there are Scots pines, there are pine martens.

Red squirrels are an important prey animal, but it will be quite a while before these three young kits are up to catching one.

For now, their lives are about scratching behind bark to find bugs and beetles.

[ Marten screeches ] ♪♪ ♪♪ The world around Wildheart is complex and diverse.

Home to 172 insect species... 200 fungi species... and a rich array of birds and mammals, each part complements the other.

♪♪ But this world is about to come under attack.

♪♪ As the Jacobite revolts of the 18th century are suppressed, the people of the Highlands face a cataclysmic change.

♪♪ Farming and land use is going through a revolution of its own.

Landlords are changing the ways farms are run, creating larger and larger open spaces.

♪♪ The rights of clan members to farm their own small crofts are removed, and whole communities are being forced out, to work on the coast or even encouraged to emigrate to new lives in North America or Australia.

♪♪ The great Caledonian Forest stands in the way of these new systems of farming.

♪♪ And by the early 19th century, Wildheart's forest has been reduced by 85%.

♪♪ ♪♪ It's a still, cool morning in April, and the forest stands shrouded in mist.

♪♪ Wildheart is now one of the largest trees in the forest.

It has the strongest and thickest trunk here.

The cold snap hasn't been enough to deter the black grouse from lekking at the forest's edge.

[ Grouse calling ] [ Grouse screeches ] Like their larger relatives the capercaillies, male black grouse display and skirmish in a series of impressive dawn battles.

[ Grouse screeching ] It's all about holding onto the best patch, and the females will choose the male with the most impressive dueling skills.

[ Grouse screeching ] As spring turns to summer, Wildheart gains new tenants.

♪♪ [ Eagle calling ] ♪♪ By July, a pair of young golden eagles are sitting on a platform of branches and twigs.

It's a tribute to the resilience and strength of Wildheart that the eagles have chosen to build here.

♪♪ It's more usual for golden eagles to choose craggy mountaintops for their homes, but they feel secure and confident in the branches.

♪♪ ♪♪ And once built, an eagle nest can last for many years.

♪♪ The chicks are 8 weeks old and growing fast.

Both parents hunt, seeking out hares on the bare mountainsides that are just a couple of wingbeats from Wildheart'S ever-shrinking forest.

They're still a month away from fledging.

But other youngsters face change even more imminently.

♪♪ This 10-year-old boy has a date with destiny.

He's come here to bid farewell to the lochs, forests, and mountains he's known all his life before emigrating with his family to America.

♪♪ ♪♪ His name is John Muir, and since he could walk, nature has been his inspiration.

♪♪ Recording all his thoughts and feelings through words and pictures, his ideas will shape the way that humanity views not just the forest but the wildlife of the entire world, eventually giving rise to the idea of protecting nature through National Parks.

♪♪ A month later, and the two golden eagle chicks are close to fledging.

One is considerably larger than the other, and the nest is now littered with bones and debris.

[ Flies buzzing ] Soon they will follow their parents into the Highland skies and leave Wildheart's forest behind.

♪♪ Young John Muir has also departed.

He's now a thousand miles away, on a schooner bound for a new life in America.

♪♪ In his new home, he'll exchange the Scots pines of the Highlands for the giant redwoods of California.

But he hasn't forgotten the Caledonian Forest... and he never will.

♪♪ ♪♪ As the 19 century draws to a close, Wildheart is now a grand old survivor.

More than 350 years old, the tree is one of the oldest in the forest.

But it's very much on the front line.

The pine forest's resources are being used for industry and war.

Its frontiers have been pushed back by sheep farms and shooting estates.

♪♪ The great Caledonian Forest is now a tiny fraction of what it once was.

♪♪ Less than 5% of what once stood here is left... and the forest is now spilt into 35 fragments, islands of diversity among the bleak, bare mountains.

♪♪ The beaver, wolf, lynx, and osprey are gone.

♪♪ But some creatures still return here every year... ...animals who have the Highlands at the very heart of their life cycle -- Atlantic salmon.

♪♪ If the natural world has a symbol for surviving in the face of impossible odds, that totemic animal would surely be the salmon.

♪♪ Highland salmon travel into the rivers from their ocean home after one to four years of feeding in the cold saltwaters off Greenland and the Faroes.

[ Sea birds calling ] Dolphins wait to ambush them in Highland estuaries as they enter river systems... ...tossing and turning the unfortunate fish into the ideal swallowing position.

♪♪ The surviving fish power onwards towards distant spawning grounds among the forest fragments.

♪♪ But more barriers lie in their way.

♪♪ The fish are resolute in their desire to move on.

Their bodies are equipped with powerful muscles that spring them across the most challenging waterfalls.

♪♪ They will never give up.

♪♪ ♪♪ Finally, back in the streams where they themselves hatched, the salmon spawn before their lives end.

♪♪ But their bodies are carried back to nurture the living forest.

♪♪ ♪♪ As Wildheart lives through the first half of the 20th century, the forest is at its lowest point.

♪♪ But things are changing.

♪♪ Across the far Atlantic, young John Muir has grown to inspire a new vision of the natural world.

His ideas have inspired a network of American National Parks, places where the natural world nurtures, revitalizes, and complements humanity.

♪♪ Places where rare species can recover.

♪♪ ♪♪ It's a mild sunny day in March.

Wildheart still stands at the edge of her forest... ...new saplings fighting to earn their place around the base of her gnarled trunk.

Something special is about to happen -- the return of a traveler who hasn't been seen here in many decades.

[ Bird calling ] ♪♪ ♪♪ ♪♪ It's an osprey, a specialist hunter that has come to reclaim this patch of forest and river.

♪♪ Although ospreys have been missing from Wildheart's forest since the turn of the century, conditions are still good for them here.

♪♪ Lochs and rivers still have a healthy population of trout, an osprey's favorite quarry.

♪♪ ♪♪ ♪♪ This expert fisherman has a superb technique.

♪♪ But not every dive produces a catch.

Three out of four strikes is unsuccessful.

♪♪ Despite the osprey's superior eyesight and a dive speed of 80 miles an hour, a trout can easily evade the hunter's talons.

♪♪ ♪♪ A successful strike.

But the fish isn't beaten yet.

♪♪ ♪♪ The hunter's inward-curving claws and adhesive scales on the inside of its feet grip the fish tightly.

♪♪ But it's trying to swim down, pulling the osprey with it.

Predator and prey are close in weight.

Lifting off from the water will need a titanic effort.

♪♪ ♪♪ Summoning every last drop of resolve, the osprey uses the power of its long and broad wings to lift the trout from the surface.

♪♪ A perfect prize for a mate.

♪♪ ♪♪ Not far away is the osprey's nest, the first to be built in Wildheart's forest in half a century.

♪♪ But this nesting attempt will not succeed.

♪♪ Illegal egg collecting is still a popular activity in Great Britain.

♪♪ Ospreys will need help to colonize Wildheart's forest.

♪♪ [ Footsteps approach ] By the late 1950s, a new breed of wildlife warrior has emerged.

This is Roy Dennis... a young English ornithologist with a passion for Scottish ospreys.

He has a job as the warden protecting the only breeding pair of ospreys in the British Isles.

Endlessly vigilant, he's determined to give the ospreys the best possible chance of success.

That means trimming low branches from trees that could give egg collectors access to the canopy and organizing volunteer patrols.

But, above all, watching and waiting day and night... ...until finally, in the summer, the ospreys succeed.

[ Ospreys calling ] ♪♪ ♪♪ And the first chicks fledged in Scotland in the 20th century take to the skies.

♪♪ ♪♪ ♪♪ But what of Wildheart and her kin?

Can the Scottish forest also return from the edge?

♪♪ ♪♪ ♪♪ The tree stands alone and in the open now.

At 480 years of age, Wildheart is nearly as old as a Scots pine can be.

Its life will be over soon.

And what times it has born witness to.

Times in which humanity has pushed the planet into a dangerous place.

Times in which so many species have vanished from the forest.

But things are changing.

♪♪ And now in the 21st century, there's a new sense of awareness that people can and must do something.

♪♪ In the last 20 years, organizations like the John Muir Trust have planted more than a million successors to Wildheart.

♪♪ Although the ancient tree itself may be closer to the end, the children of the 21st century are not prepared to let her kind die.

♪♪ For the sake of Scotland and to safeguard the future for us all, Wildheart's descendants are marching forward across the hill.

♪♪ The Caledonian Forest will rise again.

♪♪ ♪♪ ♪♪ ♪♪ ♪♪ ♪♪ To learn more about what you've seen on this "Nature" program, visit pbs.org.

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