Big Little Journeys (2023) s01e03 Episode Script

1
All around the planet,
billions of animals are
on the move
making incredible journeys.
The most amazing
of these are the smallest.
This series uses
the latest camera technology
to follow six tiny animals
on the biggest adventures
of their lives
as they travel through
extraordinary landscapes
where every little step counts.
In this episode,
a Madagascan chameleon makes the
journey of her lifetime.
And a Scottish water vole faces
Highland Giants to find a new home.
The greatest adventures
are the smallest.
Kirindy Forest, Madagascar.
This tiny chameleon is
a few minutes old.
Half the size of a matchstick,
she has spent seven months
underground,
developing inside her egg.
And now her own eggs are already
growing inside her.
She's starting a journey
to find a male.
These chameleons only live
for a matter of months.
Her instincts drive her to climb.
Built for the ascent,
her feet can swivel
helping her cling to cracks.
She heaves her way upwards.
The climb is 150 times her body
length,
like a human scaling
the Empire State Building.
Five metres up,
she's in a very different world.
A dense network of branches
that give shade
and create aerial highways.
She's hungry.
She has never eaten before,
but knows food when she sees it.
Flies.
They have split-second reflexes
but she's born with the skills
of an assassin.
Her eyes search almost 360 degrees.
A target.
Both eyes lock on
with binocular vision.
And she fires her lightning-fast tongue.
It's twice the length of her body
and as sticky as honey.
She catches up to 100 flies a day.
It takes two weeks
to double in size.
The fading light
and decreasing accuracy
is her cue to get some sleep.
Being light, she can reach places
where most predators can't.
The thinnest branches
are the safest.
Her pincer-like feet clamp
onto the branch.
It's like sleeping on a tightrope.
A cat-eyed tree snake.
A metre long.
Over ten times bigger than she is.
It's still light enough
to reach her.
Deep in slumber,
the chameleon is
at her most vulnerable.
The snake's approach causes
tiny vibrations along the branch,
that the chameleon can sense
even when asleep.
And when the snake is too close
they wake her up.
All she can do
Is let go.
Her radical move is a deliberate
escape strategy.
But it has put her right back
on the dangerous forest floor
in the middle of the night.
6,000 miles away
the Cairngorms of Scotland.
Home to one of Britain's
shyest animals
a water vole.
This female is three months old
and small enough to fit
in the palm of a human hand.
She is busy preparing her small
territory by digging burrows,
ready to raise a family.
She must eat two thirds of
her body weight every day
to stay in prime condition.
There's just a few weeks
left to mate and raise pups
before the first signs of winter.
To attract a suitor,
she strategically leaves
droppings around her territory.
Today, they've got some attention.
A vole's worst nightmare.
An invasive American mink.
Its ultrasonic hearing can detect
the slightest squeak.
To a water vole,
its odour is a trigger to run.
Just one mink could wipe out
every vole in this glen
in just a few weeks.
She's lost her riverbank home.
She must now travel into
the unknown to find a new territory
in which to have her first pups.
Two miles into the glen
she's alone, homeless
and exhausted.
She needs a place to rest.
A burrow.
She could make it her new home.
It's occupied.
A pregnant water vole.
This is her burrow.
And she will fight to the death
to defend it.
Being less experienced,
the best option is to flee.
But the path ahead
is blocked.
In Madagascar,
with her biological clock rapidly
ticking away,
the chameleon is searching for
a way into the trees.
She's unaware of the predators
that lurk in the dark.
A way back up.
Things are not as they seem.
As she travels,
her cover disappears.
She's on a dirt track,
cut through the forest by humans.
Drawn towards a tree trunk,
she hauls herself upwards with
every ounce of energy she has left.
Finally, she can get back to sleep.
Dawn reveals a harsh reality.
Once there were trees
all the way to the horizon.
Now there is nothing.
It's a long way back.
Finally in the safety of a tree.
But she's facing another problem.
Being shaken off
is the last thing she needs.
Red-fronted lemurs.
Feeding on the fruit
in this neem tree,
they've created a sticky mess.
A magnet for flies.
A chance to get her energy back
before she continues her journey
to find a mate.
The vole's search for a new home
has taken her three miles
into a glen.
Ahead of her lies water.
She's spent her entire life
around streams.
But with poor eyesight,
she has misjudged how far it is
to the other side.
This loch
is vast.
In the cold waters beneath her
monsters lurk.
Giant pike,
four times her size,
could swallow her whole
if she doesn't drown first.
She's never swum more than
a few metres from land before.
The further she swims from shore,
the more likely
she will be detected.
Once a pike senses ripples
most prey don't stand a chance.
But this water vole
has made it to the other side.
For now, she's safe.
Running water.
It's the sound of home.
If she follows it, she might find
the habitat that she's looking for.
The higher she climbs,
the rockier it becomes.
200 metres up,
there's trouble.
A golden eagle.
30 times bigger than a water vole.
With vision five times
more powerful than a human,
it could spot a vole
from over a mile away.
She will have to sleep here tonight.
In Madagascar,
four months have passed,
and the chameleon has reached
a pivotal moment in her short life.
She has undergone the most
extraordinary transformation.
She has become an adult.
Now as long as a human finger,
her skin is a kaleidoscope
of colour
Created by special
light-reflecting nanocrystals
in her skin cells.
A chameleon's colour is primarily
used for communication,
and it changes with her mood.
Her most important signal
is a crimson spot
Indicating that she is ready
to mate.
Her eggs are fully grown
and visible through her skin.
Now she needs to find a male
to fertilise them.
She needs to secure an area
to show off her colours.
But every female of her species
is on the same biological clock
all vying for the attention
of a male.
Already, she has competition.
Females can't risk damage
to their delicate eggs.
They rarely make contact.
Instead they rely on
elaborate warning displays.
She attacks from below.
Having forced her rival away
she's claimed this area
as her own.
She can now dazzle her colours.
She's attracted a male.
There's two.
They must prove their worth.
They are twice the size of her.
Built for combat.
The bigger the nose horn,
the more attractive the male.
And the taller the head crest,
the more powerful the bite.
These two gladiators
are evenly matched.
She monitors every movement
from a safe distance.
The most dominant male
will pass on the strongest genes.
They must fight it out
to win her favour.
Unlike females,
they don't hold back.
This could be the last battle
of their lives before they die.
It will only end
when one backs down
and falls.
She allows the victor to approach.
After mating, they will never
see each other again.
With her eggs fertilised,
there is only one more stage
of her journey to complete.
To find a safe place to lay them
before her life comes to an end.
The water vole is five miles
from her old riverbank home.
Her search has taken her
to altitude.
She's in alien territory
but keeps climbing.
She's 700 metres up.
Before her lies a new frontier.
With the threat of the eagle,
she must move on quickly.
She's lost a lot of weight
and is depleted of minerals.
She'll need more than just grass
to get her strength back.
Red deer.
They may provide
just what she needs.
An old stag's antler,
packed with minerals.
100 times more calcium than milk.
A few nibbles is all she needs.
This is prime water vole habitat.
Further into the glen,
there's a burrow.
There is something here.
It's just a harmless toad
taking shelter.
With no sign of
a resident water vole,
she's found a new home.
If she can find a mate,
she will still have time
to raise a family.
With darkness falling,
she can rest.
The chameleon is five months old
and has reached old age.
Nearing the end of her journey,
she must find the perfect spot
to lay her eggs.
She has no time to waste
on an approaching male.
He's too late.
Puffing up her body
and expanding her skin cells,
she turns from green to black.
A clear signal to back off.
Instinct drives her towards
the forest floor.
Now a beacon of colour,
she stands out
amongst the leaf litter
and is slower,
weighed down by eight eggs,
a third of her body weight.
She needs to head away
from tree roots
to a place where she can dig
and with just the right amount
of sunlight to incubate her eggs.
With every step,
she could be spotted.
A giant hoghose snake,
almost two metres long.
Her only defence
is to rock gently
to try to look like
a leaf in the breeze.
This snake is an egg-eater.
The chameleon needs to wait
for the coast to be clear
before she can start laying.
She's found the perfect spot.
Her whole short life has been about
getting to this moment
and her time has almost run out.
With her last ounce of energy,
she covers her eggs.
Her life's journey is now complete.
In her last moments,
her skin erupts with colour
as if uttering her last words.
She's not the only one to have made
such an incredible journey.
Every chameleon of her species
is now dead.
All that remains
are thousands of eggs
buried beneath the soil
of Kirindy Forest.
Time capsules,
evolved to survive
the deadly dry season
until they hatch en masse
when the wetter weather returns
in seven months' time.
Having found perfect habitat,
the water vole is scent marking
the boundaries of her new territory.
But she needs to mate
within the next few days
to ensure any pups
survive the winter.
100 metres from the burrow,
she sniffs a distinctive odour.
A latrine.
There's a well-trodden path
and the chopped up
leftovers of a meal.
At last - a male.
The voles here have
lighter coloured fur.
A sign that they have
different ancestors.
But attractiveness has little
to do with fur colour.
The most important thing
to her is his fithess.
Crucial if her offspring are
to inherit genes
essential for survival
in the Highlands.
A game of chase is
a good test of his stamina.
She leads him to her new burrow.
Her journey is complete.
She's found a mate and a new life
eight miles from where she was born.
Three weeks later
and a new journey begins.
Motherhood.
Filming six little animals required
a collaboration between TV crews
and scientists around the world.
- Wow.
- Oh, wow.
Look at that.
Over two years, the team
filmed on five continents
in order to follow these journeys.
The most remote location was western
Madagascar's Kirindy Forest,
the home of one of the most
extraordinary journeys of all.
Travelling in the cyclone season,
the first challenge was
getting to the forest.
But the team's journey comes
to a halt when a fallen tree
blocks their only way in.
It's a long way back for help.
At least someone brought an axe.
Yeah, it looks like pretty tough
going, so could be here a while.
Four hours later,
progress is slow.
With the tree finally
chopped into pieces,
they must still drag it out the way.
There are several miles to go yet.
We've just arrived after
13 hours of driving.
I'm amazed that the car's actually
made it through the amount of water.
We've no electricity
and it's absolutely torrential rain.
With a break in the rain,
the team can finally start
searching for the chameleons.
One of the scientists studying
the forest's chameleons
is Ludo Raoelina.
During the day,
it's so difficult to find them.
It's better to search at night.
Finding a reptile no bigger
than a human finger is challenging.
Luckily, chameleons turn pale
at night and sleep
at the end of branches, making them
easier to find by spotlighting.
Cameras at the ready,
things finally seem to be
going well for the team.
Whoa!
Did you see that?
We were just about to start
filming and just, yeah.
Just torrential.
Just so wet.
You could literally wring me out.
Literally wring me out.
Filming has to stop.
After several days,
the storm passes,
but the fleeting life cycle
of the Kirindy chameleons
is moving fast.
Ludo is joined by
Christopher Raxworthy,
who has been studying chameleons
in Kirindy for decades.
I have been fascinated
with chameleons
since I was a young boy and
Madagascar was always
a special place.
If you want to see these chameleons,
Kirindy is the place to come to.
Kirindy isn't just a
haven for chameleons.
This forest is incredible.
Loving all of the amazing animals
that we're finding in the forest.
We've seen sifakas and brown lemurs
and loads of beautiful birds,
beautiful butterflies.
Some of the wildlife has taken
a shine to one member of the team.
So, Owen and I are currently
in a tornado of flies.
You having fun, Owen?
- No.
Why are you not having fun?
Cos the flies like me too much.
Despite the challenges,
the team are able to document
every element
of this extraordinary life cycle
for the very first time.
But they may also be filming
this for the very last time.
These chameleons hatch, grow up,
and die during one season.
This unique life cycle has left
them very vulnerable.
It seems like a very risky strategy
to actually put literally
all your eggs in one basket.
You could imagine
if the eggs didn't hatch,
then there's no backup generations
to keep the population going.
With their lives so intimately
in sync with the seasons,
a shift in the climate
could be devastating.
The rainy season now starts in
Madagascar perhaps as late as
two months later than when I first
started working in Madagascar.
And it's not just the
climate that is changing.
The environmental pressures
on Kirindy have increased
over the last 20 or 30 years.
And so the great news is we have
a lot more forest now
which is protected with inside
reserves, but we also can tell
from satellite images and from
personal experience that we can
still see ongoing declines in
terms of the total forest area.
Over the last 70 years,
half of Madagascar's forests have
been destroyed, putting much
of its unique wildlife,
including the chameleons,
at risk of extinction.
Sadly, I have seen forests
that I worked in and love
being degraded and cleared,
and so that's a very painful
experience to sometimes see
that kind of biodiversity loss.
Ludo and many other local
scientists are determined
to preserve the remaining wildlife.
The work of dedicated
conservationists around the world
is helping the tiny animals
featured in this series
to continue their journeys for
many generations to come.