All language subtitles for BBC.Earths.Greatest.Spectacles.01.of.03.New.England.1080p.HDTV_english

Our planet is
a place of constant change.

Each year, the seasons shift
and life is transformed.

But there are places where the
changes are so epic in scale

they can be seen from space.

In this series,

we reveal three of the most
miraculous transformations.

The islands of Svalbard -
within a few weeks,

frozen wastelands burst into life.

The African Okavango -

a desert transforms into
a magical waterworld.

And the mysterious forests
of New England -

erupting in a blaze of
seasonal colour.

Life finds the most ingenious
and surprising ways to thrive...

..in the world's fastest-changing
landscapes.

New England - home to the most
colourful forest in America.

Stretching across six states...

..from Maine in the north
to Connecticut in the south.

Every year, millions of people
flock here to witness

one of the planet's greatest
spectacles,

known here as the fall...

..when billions of trees explode
into a riot of red, orange and gold.

There's nowhere else on Earth
quite like it.

But despite this beauty,
there's a battle raging.

One that holds the secret to this
magical forest's most

flamboyant display.

The story of the fall begins

while winter still has
a grip on the forest.

17 billion trees,
rich with maples and oaks,

wait in suspended animation.

Amongst them,

many of New England's animals
are hibernating from the cold.

But America's tallest mammal
remains at large.

Moose survive by chewing on twigs.

Their calves will be
born in just two months...

..and their survival will
depend on the same

chain of events that will fuel
the forest's climax of colour.

As the weather warms,
water courses through every tree...

..and it picks up sugar
stored in the wood.

This liquid energy is the life
force of the entire forest.

It's so rich with sugar that maple
syrup is made from it.

The spring sunshine warms
the land...

..and the sugar surges faster...

..fuelling the growth of
nutrient-rich buds.

These tiny packages contain
everything needed to build a leaf.

But from this point on,
each tree faces a battle.

All across New England,
twigs are coming to life.

These creatures spend the winter
disguised as twigs.

Looper caterpillars.

They awake with the warmth
and immediately begin to seek out

the freshest buds,
on a hunt for sugar.

Nearby, hundreds of
baby tent caterpillars

hatch from their winter eggs.

Each smaller than a grain of rice.
They join the feast.

Swarming along the branches,
a torrent of bud destruction.

This is just the first wave
in a battle that will escalate

through the year.

The buds race to
open before they can be attacked.

Gradually, the first flush of green
spreads across the forest.

But it will be a few weeks before
the leaves are fully expanded...

..and they will need a constant
supply of sugary

sap from under the bark.

In some trees,
that sap is also at risk.

The warming spring weather attracts
an animal with a serious

sugar addiction.

TAPPING

All the way from Mexico,

he's one of the first to come back
after the trees wake.

The yellow-bellied sapsucker.

His beak hammers six times
a second...

..wounding the tree deeply...

..and chiselling into the vessels
carrying the precious sugar.

His feathery tongue quickly laps up
the weeping liquid.

On this tree last year,
he dug hundreds of holes,

but now, all the wells are dry.

It's not enough to deter
a determined sapsucker.

He can dig as many as 1,000
holes in a season.

And on another tree,
he's excavating a nest.

If he finishes it
and keeps his wells running sweetly,

he could attract
the attention of a female.

But there's another bird that could
scupper his plans.

A ruby-throated hummingbird.

He's followed the sapsucker all
the way from Mexico.

His wings beat 80 times a second,

putting him
on a calorific knife edge.

The weeping sap is the best
source of sugar currently available,

and feeding at 15 sips a second,
he can quickly drain a well dry.

He's too fast for the sapsucker
to chase off...

..so the sapsucker opens more
and more wells.

Eventually,
despite the interruption,

he finishes off his nest,
creating a deep hollow in the tree.

Now, everything is prepared.

Despite relentless attack from birds
and insects,

the warming weather keeps
the trees pumping sap,

and, as the day length increases,
the leaves continue to inflate.

As the leaves grow, they start to
shade the forest floor.

In anticipation, the plants
down below wake from their stupor.

The flowers must attract
a pollinator before all

the light is stolen.

Now, hummingbirds can feed on
their favourite source of sugar.

Nectar.

In turn helping
to pollinate the flowers.

A looper caterpillar feeds amongst
the flowers, too.

He's no longer hiding
amongst the twigs.

This master of disguise has
a different trick up his sleeve.

Swaying back and forth, he mimics
a flower moving in the breeze.

He sticks petals to his back so that
he can feed unnoticed by predators.

And there's a whole army of flower
arrangers sporting the latest

spring fashion!

As the sun strengthens,

the building sap finally forces
the leaves to fully unfurl.

As many as 200,000
leaves on every tree.

Together, they grow enough foliage
to blanket an area six times

the size of New England.

As the leaves expand,

they produce one of nature's most
powerful chemicals.

Chlorophyll.

This green pigment catches
the sun's energy to power

a reaction crucial to all life.

Photosynthesis -
creating sugar from sunshine.

This sugar is
essential for the tree to grow,

but it's now in easy reach of
New England's hungriest animals.

A moose.

Named by the Native Americans
as moosu, "he who strips off",

they are leaf-eating machines...

..and can strip a branch clean
in seconds...

..but the trees can defend
themselves.

In response, they flood their leaves
with a repulsive chemical

called tannin.

So moose must constantly roam to
seek out fresh ones.

But this female doesn't want
to travel far.

She has twins
and they're just two weeks old.

Until now, they've remained
hidden in the shade of the forest.

With the leaves now loaded with
unpleasant tannins,

she needs to find
an alternative food source.

She leads the twins
away from the cover of the trees

for the very first time.

Out here, it's a big, new world.

The mother must stay close.

Another cow and her calf are already
enjoying the coolness of the lake.

Moose have the longest
legs in North America,

which allows her to reach something
that other animals can't get to.

It's what makes this lake
irresistible.

Water plants.

Just what this mother
needs to enrich her milk...

..because they're packed with
nutrients

washed out of the leaf litter.

The twins will increase in weight
tenfold over the next few months.

It's not just the females who
need the nutrients.

Big bulls are here to
feed for a different reason.

To grow their antlers, one of the
fastest-growing animal organs.

They keep a safe distance.

Neither wants to
damage his prized possessions.

Because their racks are not
just for fighting.

Male moose concentrate on looking
good...

and attracting females.

With females watching on,
it's a chance to show off.

A good try,
but at this time of the year,

this female's attention is still
fully on her calves.

It won't be
until the fall that she will be

back on the market for a mate.

Late spring, the busiest time

for the forest's most notorious
tree-eater.

Signs of his appetites
surround almost every lake.

The beaver, New England's most
industrious animal.

His lodge is his castle, built
of sticks and hardened by mud.

But his masterpiece is his dam.

Over 50 metres long and built
of thousands of logs and branches.

For 20 years it has held back
the water to create a moat -

a defence against predators.

But this security comes at a price.

The dam needs constant maintenance.

A leak.

He's going to need supplies.

To avoid being spotted by predators,

beavers work under
the cover of darkness.

There iron-infused teeth make
powerful tools with which they can

fell a tree ten inches wide
in just a couple of hours.

SNAPPING

Fixing a leak can take all night

and into the morning.

He stirs up mud, using this mortar
to seal the cracks.

But fix one leak...
and another is sure to spread.

A beaver's work is never done.

All this work isn't
just for his own security.

MEWING

In spring, a beaver's lodge is
busy with the activity of baby

beavers and their
sounds as they call for milk.

MEWING AND PURRING

This is a crucial time to practise
using their teeth before

they too are unleashed onto
the forest.

PURRING

The beavers of New England fell
millions of trees every year.

But surprisingly, it's this that
makes them heroes of the forest.

By removing softer trees,

they create large open spaces where
red maple saplings can take root.

And they leave bigger hardwoods
standing, like maples

and oaks,
with space to spread their branches.

With more leaves to create sugar,
trees can grow ten times faster,

and their colours
in the fall will be much brighter.

Beavers have helped to create
a forest rich with maples and oaks.

But 400 years ago, something
happened that was to rapidly

speed up what the beavers
had started.

Clues to this event can be seen
threading through the forest.

Stone walls.

240,000 miles of them.

Enough to reach the moon.

In 1620, British settlers
landed on these shores.

Attracted by tales of green
and pleasant lands...

..they had hoped to create
a prosperous life.

What they encountered was
an ancient dark forest,

creaking with giant trees.

And haunting sounds
they had never heard before.

BIRDS SQUAWK

The trees towered above them,

far higher than any
they had seen in Britain.

The biggest of them
all was the white pine,

said to have reached
as high as 200 feet.

By royal decree, the King of England
claimed every one with

a diameter greater than 24 inches.

They were shipped across the
Atlantic for use as the masts

of the Royal Navy.

The rest were left for settlers.

They felled trees to build homes,
churches and mills.

Many animals, like mountain lions

and wolves, were wiped out
as the wilderness was tamed.

By 1850, almost all of New England's

forest had been chopped down,

and much of this was turned to
farmland,

surrounded by stone walls.

But then everything changed

as richer farmland and gold
was discovered in the west...

..and many of the settlers
chased their fortunes elsewhere.

Towns like Livermore disappeared
as quickly as they had been formed.

Slowly, the trees of New England
grew around the ruins

and reclaimed the land.

This new forest was very different.

By chopping down
the old-growth trees,

people had given fast-growing maples
and oaks a chance to claim the land.

They grew back in greater numbers
than ever before,

and today they dominate this forest.

From now on, there would be nowhere
else more colourful in the fall.

Today those stone walls are highways

for one of New England's
busiest animals.

The chipmunk.

There can be as many as 15
living in every acre...

because New England
is a chipmunk paradise.

The stone walls help them
to get around the forest

and keep an eye out for predators.

And the new forest provides
all the acorns and maple seeds

a chipmunk can eat.

Today the forest is treasured,

and 80% of New England
is covered in trees,

ensuring the fall
remains rich and colourful.

Because vast areas are uninhabited,

in many places the sky is dark
with little light pollution.

New England is further south
than the UK.

But it's dark enough
that on special nights

the distant northern lights
can be seen shining.

The growth of the new forest
paved the way

for wildlife to move back in,

and animals that were once
persecuted now thrive here.

DISTANT ANIMAL CALL

It's the beginning of summer.

And with daytime temperatures
now in the mid-20s,

it's warm enough to draw out New
England's most misunderstood animal.

RATTLING

A timber rattlesnake.

A creature at home
hiding amongst the trees.

It was once so feared,
a bounty was placed on its head.

But the timber rattlesnake
is making a comeback,

with a few hundred
now living in these forests.

Using his tongue, a large male seeks
the scent of a potential meal.

He's detected a log
heavy with the scent of rodents.

Coiled like a spring, he waits.

FAI NT RUSTLI NG

FAI NT PATTERI NG

Even one of the fastest hunters
on the planet

can sometimes be off target.

But he's patient.

15 hours later,
he's still in position.

FAINT RUSTLING

PATTERING

MOUSE SQUEAKS

He instantly withdraws his fangs,

eager not to damage them.

It won't take long
for the venom to kill.

He follows the mouse's scent
to claim his prize.

This should satisfy his hunger
for a few weeks.

It's the height of summer,

and the trees' leaves are
working at maximum capacity

to turn sunlight into sugar.

This is when they face
their greatest battle.

CHOMPING

Billions of bugs are on the attack.

The trees do everything they can
to resist the onslaught.

They increase the concentration
of repulsive tannins

in the surface of their leaves.

But even this isn't enough
to stop one hungry insect.

Only a few millimetres long,

this leaf miner is tunnelling
under the skin,

where he can avoid
the bitter tannins

and get to the juicy, sweet bits.

Under the safety of the leaf itself,

he devours so much green chlorophyll

that the leaf can no longer produce
the sugar it needs to stay alive.

In just two days,
he leaves a trail of destruction,

and his appetite
shows no signs of slowing.

Most insects are too big
to squeeze inside a leaf,

so they must be more selective
in how they attack.

Many eat carefully
between the veins,

avoiding areas with higher
concentrations of tannins...

..Ieaving the leaf
skeletonised in their wake.

The bigger caterpillars get,

the more they can process
the leaves' unpleasant chemicals.

And working en masse, caterpillars
can devour a leaf in minutes.

But they themselves could easily
fall prey to birds.

So disguise is the key
to their success.

Some mimic dangerous New England
animals to deter their predators.

Swallowtails have eye spots
to look like snakes.

The hag moth caterpillar
resembles a big spider.

And the fur of this one
makes it tricky

for a predator
to get to the soft bits.

But the most cunning disguise of all

is to mimic the parts of the leaf
that they've already eaten.

Many New England caterpillars look
like nothing more than leaf damage.

Filling in the gaps
with their bodies

makes them less visible to birds.

New England is swarming
with undercover caterpillars.

But there's one predator that
caterpillars can't hide from.

Because here the trees have an ally.

An army is being mobilised.

These are the Allegheny mound ants,

and the trees
are their hunting grounds.

Like lions in the leaf litter,
they hunt in a pack...

..efficiently trimming the hairs

so they can get
to the sugary juices...

..draining the caterpillar dry.

But this isn't food for THEM to eat.

In the warm interiors
of their mounds,

the summer heat
is incubating the next generation.

Caterpillar juice is the perfect
nourishment for a growing soldier,

supercharged with sugar that the
caterpillars stole from the leaves.

Soon they will be ready
to help the colony expand.

Every year
ants dig miles of tunnels

and excavate as much as
12 tonnes in every acre.

This aerates and breaks down
the leaf litter,

which fertilises the soil.

Trees with rich soil
and ant protection

produce more sugar,

they're brighter,

and they will hang on to their
leaves for longer during the fall.

Despite the battles
raging through the forest,

billions of leaves
continue to produce sugar.

This is transported down the trunk,

where it's stored
to replace the tree's reserves.

Each will gain as much as 100kg in
weight before the end of the year.

FAI NT TAPPING

BIRD CALLS

The yellow-bellied sapsucker
has attracted a female,

and in their nest they have four
young chicks just a few days old.

CHICKS CHEEP

Their parents bring back food
20 times every hour.

BIRD CALLS

It's exhausting,
keeping up with the demand.

CHICK CHEEPS

The summer sap is sweeter,

and it attracts a swarm of insects.

This is why the father has been
obsessively digging wells -

because the sap leaking from them
is now bait.

And not even the trees' allies,
the ants,

can resist a nibble
of the free-flowing sugar.

CHICK CHEEPS

For the chicks to grow,
they need protein.

Sugar-coated bugs make up
two-thirds of their summer diet.

Because of the constant supply
of insects,

the chicks increase in weight
by 16 times

in just four weeks.

CHICKS CHEEP

And they're already learning
the art of tapping for themselves.

CHICKS CHEEP

In three months' time,

they will depart the cooling forest
for warmer climates in the south.

This will give the trees a chance

to repair the damage
before the summer ends.

This female rattlesnake has spent
three months basking in the sun,

but daytime temperatures

are now dropping as low
as 14 degrees Celsius.

Being cold-blooded,
she is the first in the forest

to feel a chill in the air
as the days draw in.

She's getting too big for her skin,

but yawning widely
helps to loosen it.

And snags in the leaf litter
help her to undress,

peeling away the scaly layer.

This lethal hunter is now ready.

In a safe and secure place,
specially adapted for filming,

she waits.

Through the night, months
of preparation comes to an end.

She's given birth
to seven tiny rattlesnakes.

Only 20 centimetres long,

and already their sharp fangs

are fully loaded with potent venom.

Unlike most other snakes,

timber rattlesnakes

carry their babies inside
their bodies to keep them warm.

And there's one more on the way.

The mother's work doesn't end there.
Her maternal bond is strong.

Having the fiercest mother
in the forest,

there's very little that could
threaten these baby snakes.

One by one, they snuggle
into the safety of her coils.

It won't be long until
the cooling fall weather

forces New England's rattlesnakes
to lead their babies

to underground dens,

where they will hibernate
as families until the spring.

The shortening days
and cooling weather

trigger a change in the behaviour
of New England's biggest animal.

Male moose have been growing
their antlers all year,

and now they're dressed to impress.

And finally, the females are open
to their advances.

FAINT BELLOW

But some moose
have more luck than others.

SPLASHING

This younger male has been
following a female for weeks

in the hope
of getting her attention.

It's tiring work,

and to make matters worse,

she's still caring for a calf.

But with antlers like this,
how could she possibly resist?

He decides to make a bolder move
before a bigger bull shows up.

MOOSE SMACKS LI PS

Lip-smacking
makes his intentions clear.

Her scent is irresistible.

Not the response he was hoping for.

Urination gives him a sign
that she's still not in the mood.

Even after weeks
of trying to court her,

persistence doesn't always pay off.

THUNDER RUMBLES

Fortunately, every year, thanks
to the nutrition from the forest,

a moose grows a bigger rack.

THUNDER RUMBLES

And next time,

maybe his antlers will be big enough
to impress the choosy female.

With the temperature now
constantly below ten degrees,

the leaves
can no longer work efficiently.

And with less than
12 hours of sunshine a day,

they have less time
to create sugar for the trees.

There comes a point when they are
no longer earning their keep,

and the tree must start
to close down for the winter.

At first, the effects are subtle.

Individual leaves
start to turn yellow.

Like tiny factories closing down,

the green pigment inside
each cell is dismantled.

The tree salvages all that it can,

carrying it down in the sap
to be stored in the tree's trunk.

The cooling weather
quickens the process,

until the Midas touch of fall
turns entire forests golden.

But this is only just the beginning

of the most magical
transformation of all.

The fall in New England.

While most trees are already
preparing for the winter...

..some also take this opportunity to
secure a future for their offspring.

They drop millions of
winged maple seeds and acorns.

Many will soon be safely hidden
beneath leaf fall

to await
the nourishing warmth of spring.

But they've been spotted.

Despite the cover,
there's one animal

who is able to sniff out a fresh nut
amongst the leaf litter.

A chipmunk.

His small size means that he's
unable to pile on enough body fat

to survive hibernation
through the winter.

And just when reserves
are looking a little thin...

..a new air drop
is delivered by the trees.

Perfect timing...

..if he can stockpile enough
in his secret caches.

He can squeeze four acorns
into his cheek pouches,

allowing him
to collect up to 160 a day.

It takes a lot of work
to amass a big stash.

But there's always one who's less
prepared to put in the hours.

A lazy chipmunk.

He's spotted his neighbour's acorn
and where it's being hidden.

It's too tempting.

But it's not an easy steal.

SQUEAKING

This is one chipmunk
determined to protect his stash.

The chipmunk is
a hero of the forest -

because even after all that work,

he will forget where he's buried
some of his hard-earned treasure.

And protected underground, the seeds
have a better chance of germinating.

Whether they are a tree's enemy
or an ally,

the animals of New England
have conspired

to make the fall
a season of beauty.

And one thing is for sure -

in the end,
it's the entire forest that wins.

And as the trees make their
final preparations for winter,

the best is yet to come.

As the temperature drops
towards freezing,

the trees increase the speed

at which they drain the leaves
of their goodness.

A magical new chemical
is conjured up

from within the leaves
of the maple and oak trees.

Red anthocyanin.

It keeps the sap flowing for longer
as the temperature plummets,

so the trees can hold on
to their leaves

and extract every last drop
of sugar.

The reds and oranges join the golds,

and together
they set the forest ablaze.

From an ocean of green,
every tree becomes an individual.

Red maples and oaks
burn in shades of red.

Sugar maples glimmer in orange.

And for just a few weeks
every year...

..New England
is a wonderland of colour.

These colours
can be seen from space,

spreading across this corner
of America like wildfire.

The spectacle is intense, but brief.

As the last of the nutrients and
sugars are extracted by the trees,

billions of leaves
hang on tenterhooks.

All it takes...is a breeze.

It's the last chance for their
most persistent enemy to feast.

CHOMPI NG

Caterpillars...
in a hungry race against time.

Leaf miners are still feeding
as the leaf changes around them.

They eat all that they can
before a quick getaway.

Some caterpillars chase the colour
through the fall.

The spicebush swallowtail
swaps the green costume of summer

for a golden coat.

And, having had her fill,

she sheds this new skin to form
an overwintering pupa that,

Iike a leaf, fades to brown.

Many other caterpillars turn
red and orange in the fall.

And as the leaves lose
the last of their sugar,

they climb to the edge of a leaf...

and take a leap of faith.

Amongst the leaf litter they seek
out a refuge from the winter.

In the spring,
they will emerge as moths

and unleash a new generation
of caterpillars onto the forest.

It's the end of October,

and the planet's
most colourful forest fades

as the last leaves fall.

They have given the trees
all that they need to survive...

..until the battles
begin again next year.