All language subtitles for Inside.the.Enchanted.Forests.S01E06.Extreme.1080p.DSNP.WEB-DL.DDP5.1.H.264-NTb_track4_[eng]

♪ ♪

[narrator] The toughest forests
on our planet,

are the ones that grow
where little else does.

These hostile environments
create trees

with the ability to both
save lives...

and destroy them.

Ghosts create life after death,

monsters turn trash
into treasure,

and buildings
get swallowed whole.

These are Earth's
extreme forests.

And they will stop at nothing,
to survive.

♪ ♪

Take a journey

through our planet's
kaleidoscope of forests realms.

From the frozen boreal
in the north,

to the tropical jungles
that hug our equator...

from mountain peaks,

to the ocean depths...

Marvel at the magic,

and drama, that unfolds...

as we reveal... the Secrets
of the Enchanted Forests.

♪ ♪

The Namib...

is one of our planet's
driest deserts.

Dominated almost entirely
by sand,

sources of water
are scarce here.

Yet, it is home to one of the
world's thirstiest animals.

The elephant.

[elephant grunting]

This herd, is led by its oldest
female -

the matriarch.

She has one of the toughest jobs
of any mother.

She must find water
for her family,

in this parched wilderness.

The herd are all
counting on her,

and her knowledge of this
extreme environment

to lead the way.

[elephant grunting]

So, she looks to the most
reliable guide she knows:

the desert's sparse
and scattered forest.

Only specialist desert-adapted
tree species,

such as Ana and Mopane,
have any hope of surviving here.

The Ana tree's secret weapon,

is a long taproot that can seek
out secret pockets of water

buried 200 feet below ground.

Keeping their thirst quenched
and leaves green

for most of the year.

So they shine like a beacon,
against the dry sand.

The elephants use these trees
as signposts.

This dispersed forest,

lines the route of a river
hidden deep underground.

And, the healthier the tree,
the closer it must be to water.

To stave off dehydration, the
elephants feed on moist leaves.

But, they eat sparingly.

Every tree is precious

and they can't risk
destroying future supplies.

After days of walking,

the heat and physical effort of
this make-or-break journey

...brings the herd to its knees.

[elephants grumbling]

The matriarch knows
to trust the trees.

They tell her
she's getting closer.

And soon, she spots
the final sign.

A forest of lush,
new-growth mopane trees

is a rare sight in this desert.

These young trees,
have shallow roots.

If water is within their reach,

that means it's within the reach
of elephants too.

♪ ♪

There's even enough water,
for a cooling bath.

The Namib desert
never stands still.

The coastal winds
shift the sand dunes daily

so the location of these
sporadic sources of water

are never guaranteed.

The green markers
in this desert forest

may change their course
over time,

but they will always
lead to water.

Even in the gentlest of climes,

a forest must endure
a daily onslaught...

...from hungry beasts.

In a dense, lush woodland
with plenty to go around,

trees can share the burden
of having their leaves munched

and branches stripped.

But in extreme forests,
trees are few and far apart.

In a land with limited
food and water,

a lone tree can be
a rare source of sustenance

for wandering herbivores.

And there is a real danger of
it being completely devoured.

So these trees,
need to fight back.

One such tree,
is the camelthorn acacia.

This desert stalwart is locked
in an escalating arms race

with its greatest foe...

the giraffe.

A giraffe needs to eat

more than more than 60 pounds
of vegetation per day.

And very little
is out of its reach.

To counter these attacks,
the tree has armed itself.

Covering its branches

in two and a half inch long
punishing spikes.

But the giraffe evolved
dexterous lips

and a one and a half foot long
prehensile tongue

to deftly navigate
around the spikes

and still pluck away
at the leaves.

So the acacia, enlisted
some back up.

[narrator] Its second
line of defense

comes from within
the thorns themselves.

Tiny bodyguards.

Each tree in this woodland,

has several ant species
living within it.

Housed inside the hollow thorns,
these ants will protect the tree

in return for a regular supply
of nectar.

As the giraffe's lips move in,

the ants swarm,

delivering a barrage
of painful stings.

But, this only works
on young giraffes.

Adults have toughened,
leathery lips

and appear undeterred
by the pain.

For these hard-mouthed adults,
the tree has one final tactic:

chemical warfare.

Once the tree senses
it's under attack,

it floods its leaves
with a bitter tasting toxin.

In high doses these chemicals
could kill the giraffe,

but they take a huge amount of
energy for the tree to produce,

so it releases just enough to
render the leaves unpalatable.

Finally, this works.

But the giraffe, simply goes in
search of another acacia to eat.

This may be a sparse forest,

but the trees within it
still look out for each other.

So the beleaguered acacia,
sends out a warning.

Through pores on its leaves,

it releases a waft of
ethylene gas into the air.

The surrounding trees
pick up this airborne message,

and follow suit, filling their
leaves with toxins.

Within 15 minutes, all
the leaves in this woodland

have turned distasteful.

The herd is forced to move on,

and the forest can stand down
and reset.

The tree's defenses give the
giraffe just enough time to eat,

but never enough
to destroy any one tree.

Both sides have called
a truce... for now at least.

Even a tree so hell bent
on defense,

needs to soften up for
the sake of its offspring.

Once a year,

the camelthorn acacias need
the help of a certain herbivore,

if their woodland is to survive.

These, are acacia seed pods.

The tough outer casing is
designed to protect the smaller,

more delicate seeds inside.

And the acid
inside an animal's gut

is the most effective way
to soften them up

and kick start their
germination.

As the tree drops
its ripened pods,

the fate of its offspring
lies in the jaws of others.

And the crucial element of
success,

comes down to
who is doing the eating.

Something the tree,
has no control over...

Many seed pods are doomed
before they even hit the ground.

These round holes are the work
of the bruchid beetle.

It lays its eggs directly
onto the pod's outer casing.

The newly hatched larva,

burrows its way inside
and starts eating...

By the time it re-emerges,
all fattened up,

there is little left
but a potholed empty husk.

The remaining healthy seeds

have caught the eye of a ground
squirrel.

♪ ♪

But the squirrel's teeth
and jaws are just too strong

and they grind down the pods;

husk, seeds, and all.

Turning any chance of
a new seedling into dust.

But there is one set of animals
in the desert

that can help the acacia.

This grey duiker,
is a welcome diner.

A portion of the seeds

will safely pass through
its four stomachs unharmed,

and reappear
ready to be planted.

Duikers, along with gemsbok
and springbok

are the Acacia woodland's
salvation.

And the seeds are an important
food source for them

during the long periods
of drought.

As they continue
their search for food,

they scatter the unscathed seeds
far and wide across the desert.

Planting the next generation
of tough little trees

to preserve this rare forest
in the unforgiving Kalahari.

If a tree can't tempt an animal
to eat its seed,

it must come up with
an alternative solution.

One tree in particular,

has taken their unusual
dispersal strategy

to a lethal level.

[narrator] 50 miles off the
coast of Southern Australia...

lies Lady Elliot Island.

In the heart of
the Great Barrier Reef,

this coral cay island
is one of the few

that supports its own forest.

One species of tree has
managed to get a foothold here.

The Pisonia Grandis.

An entire forest sprung
from a few deposited seeds.

But on such a tiny
secluded island,

once the forest
has reached capacity,

how does it expand
into new lands?

The nearest island is
over 20 miles away,

too far for the seeds to be
transported on the wind,

and they won't survive
in saltwater.

The trees, need a seed carrier.

During the summer months,
this forest plays host

to some 50,000 migratory
seabirds,

as they flock to this
island to find a mate.

[birds squawking]

The trees offer an attractive
site to build a nest.

At over 60 feet tall,
they provide shade

and a protective buffer

against the winds
that batter the coastline.

But it's a small forest
and there are many seabirds.

Over 40 pairs of noddies
may nest in a single tree.

In return for acting as hosts,

the seabirds gift the trees
tons of nutrient-rich droppings.

[birds tittering]

On a sandy, coral island

it is this guano that sustains
the forest and fuels its growth.

It's a match made in paradise.

And these long distance
seabirds,

make the perfect seed carrier.

They can fly
from island to island

and spread the Pisonia's
influence

throughout the archipelago.

But this is where
the plan, hits a snag.

Seabirds don't eat fruit
or seeds,

so the tree
has to find another way

for the birds to carry
its offspring...

Glue.

The Pisonia coats its seeds
in a sticky substance.

Strong enough to hold firm
on the bird's feathers,

whilst flying over the sea
to another island,

but weak enough so the seed
eventually drops off

in its new home.

However, in their ambitious
quest to colonize new islands,

the tree has gotten overzealous,

and its dispersal strategy
has spiraled.

The trees produce
so many sticky seeds,

that they often
smother the birds.

With their feathers
glued together,

and loaded down with seeds,

they can no longer fly.

The forest is unwittingly
sabotaging

its own expansion plan.

This remains the only forest
for miles.

So they keep returning
to this island,

despite the toll...

...Forest and bird,

stuck on an evolutionary path

that's hit a dark, dead end.

When forest and animal
do work in harmony,

the result can bring
a secret sweet relief

to life in a bitter landscape.

[narrator] There are very few
species of tree,

that can survive in
Australia's brutal interior.

Even the tough eucalypts have
failed to conquer these lands.

Again, it is an acacia forest
that dominates this desert.

This Australian species,
is known as the Mulga tree.

Hardy and efficient,

it is one of this arid zones'
most successful inhabitants.

Partly due to
its own partnership

with not one,
but two insect species.

The tree's branches,
are sprinkled with lerps.

These crystallised
honeydew bubbles,

protect juvenile psyllid bugs
that live off the tree's sap.

Patrolling between the lerps,
is the honeypot ant.

They won't harm the psyllids

but instead, they drink
the honeydew

encased within the
protective shells.

Diligently, the ants bring
supplies of this sweet nectar

back to the nest located
at the base of the mulga tree.

Down here, in their underground
network of tunnels,

the ants stockpile their
precious elixir

for when times are lean.

The honeydew is kept
in living larders,

that hang from
the burrow ceiling.

Specialist ants,
known as repletes,

are overfed with this syrup,

until their dangling, extended
bellies stretch to bursting.

These, are the eponymous,
honeypots.

When the desert drought
reaches extreme measures,

the worker ants
stroke a replete's antennae

and receive a ration
of the sugary liquid.

The mulga tree sustains the ant
colony through tough times,

and in return, the ants
help the tree to thrive.

Honeypot ants act like
earthworms

in the Australian desert.

They till the soil,

recycling valuable nutrients and
breaking down organic matter.

[thunder claps]

Their burrows act as funnels,

transporting precious drops of rain

straight to the tree's roots.

In the unpredictable
and extreme nature

of the Australian outback,

this two-way relationship
between insect and tree,

enables both to survive,
where little else can.

As we walk through any forest,

we can be unaware
of the extreme nature

of what lies just beneath
our feet.

In broadleaf forests,

down amongst the layers
of fallen leaves,

and broken tree trunks,

lies a world
that is rotten to the core.

♪ ♪

This, is where
hidden terrors live.

And no one, is safe.

This giant centipede
in New Zealand

can only survive
in a moist environment,

so the damp forest floor
is his chosen realm.

At 8 inches long,
it is the stuff of nightmares.

Its pincer-like legs, that move
in a hypnotic rhythm.

The fact it has eyes,
but can't see.

Its killer instinct.

The skink is safe...

...as long as it stays still.

The centipede can't see it,

but it can detect movement
through its antennae.

Do.

Not.

Move.

The centipede subdues its victim

before using its specially
adapted front limbs

to inject it with venom.

Having feasted on its innards,

the centipede returns
to its darkened lair -

until it's time to hunt again.

In this underworld,
nothing is what it seems.

Perfectly camouflaged against
the forest floor,

this is a Brazilian
wandering spider.

This spider doesn't build a web,
to wait for her food to arrive.

She goes out and hunts.

And she uses the leaf litter,
to help her.

Her fangs are packed
with the most potent venom

of any spider in the world.

And her legs, can detect
the slightest vibration

from several feet away.

So if any hiding insect
rustles a single leaf...

It's game over.

But, as these mini monsters
consume their next victims,

they are helping the forest
deal with its litter problem.

A buildup of dead leaves
could choke a forest.

All this leftover organic
matter, needs to be reduced

and recycled.

Whilst the fungi and bacteria
living in the soil

take on the bulk
of the decomposing work,

spiders prop up the process

by hunting the insects
that eat the fungi.

And also supporting
this vital service

is a very specialist
band of invertebrates,

known as The Detritivores.

Each member has its own role
to play on the forest floor.

Millipedes feast
on the tougher leaves,

breaking them down for
the microorganisms to recycle.

Voracious grubs chew
through the dead wood,

accelerating its decay

and returning its nutrients
to the soil...

...where it continues
to fuel the forest.

These hard working critters,

are paramount to the success
of our forests worldwide.

By keeping the soil healthy
and reworking every nutrient,

woodland ecosystems simply
could not work without them.

A healthy, fully functioning
forest can be a powerful force.

It can influence our climate,
support life and even...

cover up our remains.

As humans, we have undoubtedly
left our mark on this world.

But those marks,
are not always indelible.

So what happens, when we're not
there to maintain our dominance?

Over time,

nature returns to take back
what is rightfully hers.

This former prison on Gorgona
Island

off the coast of Colombia,

detained some of the country's
most notorious offenders.

But 40 years
after the last inmates left,

the surrounding forest
has reclaimed the area.

Trees need to expand
in order to grow.

Its living tissues
simply flow around

and engulf anything in its way.

Binding itself
to man-made structures,

until the two become one.

The forest, gradually swallowed
the buildings

and the wildlife returned.

♪ ♪

This process of
ecological succession,

is when nature is allowed
to follow its own path

and regenerate
an entire environment.

Across the globe,
wherever humans move out,

fast growing pioneer species
of trees move in.

In just a matter of years,
empty urban spaces

revert back into forests.

Drawing in a different set
of residents.

In the face of
human encroachment,

life always finds a way.

Even a forest full
of man-made ghosts,

can create a life
worth fighting for.

[narrator] This forest in Yala
National Park in Sri Lanka

was deliberately flooded.

The trees slowly
and silently drowned

in the newly created lake.

Preserved in the saltwater,
they remain upright,

stripped bare and knee deep
in the water.

But a lifetime's worth
of nutrients

once stored in their trunks,
now leaches into the water.

Even as a ghost forest,

the trees have created a
surprisingly fertile habitat.

[birds chirping]

Meaning it is still hot property
for many animals.

[birds squawking]

And for a bird of prey,
it's the perfect forest.

This juvenile white bellied
sea eagle,

recently left his nest

and is now looking to establish
his own territory.

And these ashen skeletons,
will suit him very nicely.

The rigid branches
support his weight,

and the lack of leaves and twigs

is far more accommodating of his
six and a half foot wingspan.

There is no requirement

for a leafy canopy
to hide from predators -

he is the predator.

And he has a clear line of sight

to pick out a target
from the lake below.

But if he wants to claim
this highly desirable area

as his own, he is going to
have to fight for it.

A rival young male

has also set his sights
on this forest graveyard,

so he attempts to run
this new arrival out of town.

♪ ♪

In an effort to throw off
his pursuer,

the trespasser lets go
of the fish...

but this isn't about food, this
is a battle for real estate.

When his competitor drops out,

the new arrival
chalks up a win.

But his victory lap,
does not last long.

The young eagles
have failed to realize

they are squabbling over a
territory that is already taken

by these resident adults.

With far superior flying -
and fighting skills -

the fully grown sea eagles

have secured this coveted spot
as their own,

and they are not
prepared to share.

♪ ♪

The youngster will fare better

in a less competitive
neighborhood.

Even a drowned forest
is a useful one.

These grey ghosts, still have
a huge ecological value

to the surrounding wildlife,

and competition
to call them home

is just as rife
as in a living forest.

Across the world,

forests have found
a variety of ways to survive

in the toughest of landscapes,

but one of the greatest
challenges they currently face

is an increasingly
warming climate.

And in an effort to combat it,
right now,

around the world,
trees are on the move.

Individual trees
might be rooted to the spot.

But, entire forests can travel.

By using their seeds.

As the planet warms,

it changes the conditions
in and around forests.

Seeds might succeed in places,
where they did not before.

Or start to fail,
where they once thrived

as habitats
become less hospitable.

The older trees start to die off

and the forest begins a slow
journey, in a new direction -

sapling by sapling.

Essentially,
the forest is migrating

towards a more
comfortable life -

moving around 10 miles
per decade.

But the rate of climate change
is accelerating

and the trees
are failing to keep up.

They need to increase their
pace and move 10 times faster,

or risk extinction.

There is a danger, as forests
are pushed beyond their limit,

some of our most remarkable
tree species will suffer.

The slow growing giants,
such as the iconic redwood,

some of which have been standing
since Roman times,

could disappear forever.

As we lose our forests,

we lose a huge ally

in the battle to slow
the warming of our planet.

Over millennia, they have fought
to thrive in every environment -

however extreme.

But the limits of those extremes
now lie in our hands.

If allowed,

our precious woodlands can
continue to work their magic,

shape our world,

and nurture
all life within them.