BARRY HUMPHRIES: As the dawn breaks across Australia,
the marsupials go to bed.
Except for the ones that don't,
because there are exceptions
to every rule in this land of wonders.
And magic does not have rules.
It has dragons...
saltwater monsters...
and miniature dancers.
What are the extraordinary tricks these animals have
in response to their world?
To endure Australia's frozen peaks...
and thrive on its harsh savannas.
To compete in its tropical rainforests.
Travelling into their worlds
we begin to understand how truly unique life is
in the Magical Land of Oz.
On Australia's highest peaks, the Snowy Mountains,
winter temperatures reach well below zero.
This true alpine wilderness
can spend half the year beneath a blanket of snow.
Very few creatures can withstand a winter on Australia's peaks,
where food is scarce.
But some tough it out.
This echidna has hibernated on and off
during the coldest months,
emerging, at the tail end of winter, very hungry.
An insect eater,
it's slim pickings while the snow encases his food source.
But as one of the most energy efficient mammals on the planet -
with a body temperature that can drop below 5 degrees Celsius -
this echidna can survive long periods in the bitter cold.
His shovel-like claws work like snowshoes.
It's a lonely march on an empty stomach.
As the days get longer and warmer,
high-country rivers carry the now liquid winter down the mountain.
Spring's arrival also means at last the echidna can feast
after months of winter's famine.
But one obstacle still stands in the way of a full belly -
a fast-flowing one.
Using his long beak as a snorkel and large feet as paddles,
he's perfectly capable of a river crossing.
He may not look like an all-terrain vehicle,
but the echidna inhabits more Australian landscapes
than any other native animal.
He will now spend 18 hours a day foraging for insects,
turning over soil and gardening the forests.
The echidna is named after the Greek goddess Echidna,
who was half woman and half reptile.
Its closest relative, the world's only other monotreme,
also has a curious blend of characteristics.
With splayed limbs, on land, the platypus shuffles like a lizard.
But in the water, she glides like an otter.
Egg-laying and beaked like a duck,
she's the ultimate mash-up.
But the combination works.
The platypus has remained unchanged in Australia
for 25 million years.
These elegant underwater hunters
are the oldest lineage of mammals alive on earth today,
living only here on the rivers of Eastern Australia.
Later on the evolutionary tree,
but in the same surrounding grasslands and forests
of modern Australia,
are the marsupials.
And the most familiar of them all is the eastern grey kangaroo.
The weight of an adult human, but head and shoulders taller,
this male is demonstrating his potency to the mob.
A thick sticky secretion from glands on his chest,
in a cocktail of fresh urine,
says, "This is my patch."
Just in case anyone doubts his authority.
He has a harem of nine breeding females
all with at least one joey.
Despite the male's posturing,
he's not the powerhouse of this extraordinarily successful species.
It's the female with her magic pouch.
So while this 10-month-old joey
is starting to explore the outside world,
another tiny baby is already developing in the pouch.
It's only the size of a jellybean.
The older joey is now being forced
to spend more hours outside the pouch
to give his mum and new sibling a break.
Like all young ones,
he knows to keep pestering, until she gives in.
With only two joeys on the go,
she is now ready to fall pregnant again...
..a fact not lost on the dominant male.
He will pursue her for days.
But rival males are a constant threat.
Maintaining his status as top roo is so taxing
that he may only keep the dominant male crown for a year
before he is toppled.
Being a kangaroo is much more complicated than it appears.
But the energy expended on reproduction is working for them.
Exploiting the farmlands, which have spread across the continent,
there are millions of eastern grey kangaroos in Australia today.
Large kangaroos are amongst the very few native animals
to benefit from land clearing
and the decline of Australia's apex predators.
So many species are gone now.
The continent's top carnivore, the Tasmanian tiger,
was hunted into extinction by the 1930s.
And the grand hunter from the skies,
Australia's own eagle,
has come perilously close to being lost.
This country's wedge-tailed eagle is one of the world's largest.
For years, it was mercilessly shot,
mistakenly portrayed as a prolific killer of lambs.
In the mid 1900s, there was a bounty on its head,
with up to 30,000 eagles killed in a single year,
their great bodies strung up on fences.
Eagles are now protected
and most farmers accept that they are no threat to their livestock.
Now affectionately known as "wedgies",
their calls again echo across the farmland.
Australia's biggest bird of prey has a chance of a comeback,
thanks, in part, to another mistake of European settlers.
Fluffy eagle fodder,
brought here over 200 years ago,
now in plague proportions.
The wedge-tail is a stunning avian predator.
For such a large bird,
her movements are deft and light.
With a 2.5-metre wingspan,
her precision, at speed, is breathtaking.
She can soar up to 2,000 metres high
and carry half her own body weight in her huge talons.
But as she surveys the landscape,
those eagle eyes pick up something curious and worth investigating.
An eastern long-necked tortoise.
Although the tortoise has an almost impenetrable shell,
he's not taking his chances.
Time to retreat.
She's sure that rock was moving.
Baffling really.
It's an old trick but a good one.
The eagle resumes her search for an easier target.
This time, it's more familiar.
In some parts of the country,
rabbits make up 90% of the eagle's diet.
The tortoise, zero.
Yet again, the tortoise beats the hare.
And eagles now are the farmer's friend,
helping to keep the rabbit population down.
Before rabbits were introduced to Australia
and so much native bushland was removed,
it was the small native animals which had the run of the land.
In the south-west of the country lie the Dryandra Woodlands.
This stand of wandoo eucalypts
is one of the last strongholds for a native mammal
which once roamed the entire continent.
As the sun hits the carpet of wildflowers
and insects begin massing on the forest floor,
a small marsupial is making its first move.
The numbat...
..closest living relative to the extinct thylacine,
or Tasmanian tiger,
is on a termite hunt.
It will take 20,000 termites to fill her belly.
Back in her den are four rapidly growing numbat pups,
which she has fed through the night.
The young are eight months old
and only just getting curious about life beyond the burrow.
One of them, the smallest and boldest, is the leader.
She's begun to explore the tree stump fortress
protecting the burrow exit.
Her siblings follow, trembling as the air hits their fur.
Each day our leader has inched closer to the fortress walls.
From here she gets a first glimpse at the world beyond.
But with every sound a warning,
the pups retreat, more than advance.
They'll do well to be cautious.
Hundreds of thousands of numbats once ranged across Australia.
Today, there are less of them
than the more famously endangered snow leopard or giant panda.
Just like the panda, numbats are specialist feeders,
needing something that's now in very short supply,
undisturbed woodland with logs for termites.
This female can smell a termite's gallery
and even feels their tiny vibrations beneath her feet.
Using her worm-like tongue,
she extracts them from tricky crevices.
Each day she swallows 10% of her own body weight.
Her young are getting braver and revelling in the sun.
The rounded snouts which have suited milk feeding
are getting more elongated by the day.
Within a month, they too will be reliant on termites.
So, the job of working out what is food and what is not
is the lesson of the day.
Except for one of them.
Our little explorer is determined to experience
what lies beyond the wall...
..while her siblings stay cautiously close to the burrow.
She takes off.
She will keep wandering further from the burrow
until one day she leaves her mother's territory and finds her own...
..crossing paths with other young numbats
also emerging from hollows in this forest.
Each one of them will need to venture and breed
in order to keep this species viable.
Over the past two centuries,
almost all of the numbat's habitat has been destroyed...
..apart from these last stands of wandoo forest.
And less than 1,000 tiny numbats are left surviving in the wild.
Where Australia's ecosystems are left intact, animals thrive.
It's as simple as that.
In far northern Queensland,
the rainforests of the wet tropics
appear as a thin ribbon of green along the coast.
These rainforests have been around longer
than any other on the planet...
..an estimated 180 million years,
far outdating the Amazon.
Australia's most secretive and unique creatures
have made the forests their home.
And everyone here is competing for spoils.
Even on the forest floor.
Thousands of species of fungi battle to dominate the leaf litter.
Despite their myriad forms,
the fungi are all engaged in similar mycological magic.
They break down wood and leaf litter
and return their nutrients to the soil...
..while slime moulds hunt down the fungi
and turn them into nutrients too.
Things live fast and die young
on this forest floor.
The pioneers of recycling, you might say,
assuming every imaginable shape.
They feed the hungry forest,
turning it into one of the earth's evolutionary hotspots.
For it was here, in the cradle of the Gondwana Rainforests,
that Australia's mammals first emerged.
As the land became more arid,
many moved out to the grasslands.
But there is one kangaroo
which has never left its rainforest home.
A shy creature rarely seen on the forest floor.
That's because its home is in the trees.
This young male tree kangaroo has evolved for a life in the canopy,
with large strong arms, big curved claws
and a pendulous tail.
But even 20 metres up, he's still clearly a kangaroo.
The monkey of the kangaroo world,
just a little less sure footed.
At almost two years old,
he has only recently left his mum to find his own territory.
Unlike his relatives at ground level,
he will live a solitary life,
only seeking out a female when it's time to mate.
But he's having trouble cutting the umbilical cord.
He can hear his mum in one of her favourite trees
and he crosses the canopy roof to reach her.
But it's not a tender welcome.
His mother doesn't want him near her.
They move to opposite ends of the tree.
Her tough love suddenly makes sense.
At eight months, the newest joey has begun leaving the pouch
and exploring her high-wire world.
Though she's wobbly enough,
a teenage sibling might topple her altogether.
For her brother,
being solitary requires its own process of evolution.
At least up in this rainforest,
he's never really lonely.
Above and below him,
over half of Australia's bird species
are in a springtime nest-building frenzy.
The sunbird uses bark and seeds to build its hanging nest.
And the fawn-breasted bowerbird makes final artistic touches
to its elaborate construction.
Most cockatoos and parrots rely on hollows.
It would seem an easier option than DIY.
But relying on hollows has left the parrot world out on a limb.
This female eclectus parrot has guarded her hollow
well before she was ready to lay.
Her green mate delivers food to her
so she can stay on sentry duty.
Hollows form slowly in old trees
so there's never enough to go around.
Unlike so many in this forest,
this one is too high to flood
and it's safe from predators.
It should be a textbook incubation.
[COCKATOOS SQUAWK]
But the neighbours nobody wants
are looking to move into this leafy suburb.
It's the sulphur-crested cockatoo.
[SQUAWKS]
Famously loud, assertive and ready to lay,
this pair want the hollow for themselves.
They begin a game of intimidation.
Unlike the cockatoos, who can breed three times a year,
the eclectus parrot is doing well to raise one chick annually.
[SQUAWKS]
But as the day heats up,
temperatures inside the nest hit over 30 degrees Celsius.
Her own body heat is raising temperatures even further.
Her eggs will cook in this oven.
With the coast clear of sulphur-crested cockatoos,
she leaves to let the nest cool down.
But they see an opportunity too.
If the cockatoos get inside, they will smash the eggs.
The cockatoos get more confident with every passing moment.
[PARROT SQUAWKS]
The female will fight to the death to protect her eggs.
Her siren colour is enough to ward off these intruders.
But colour is only one of the many ways
birds in this forest communicate.
It's only recently been discovered that 24 million years ago,
birdsong evolved in this forest.
It is the home of nature's great vocalists.
[TRILLS]
[SQUAWKS]
[HONKS]
[TWEETS]
It's also where one cockatoo has developed a sound so unique,
it wasn't thought possible for a bird.
The continent's largest cockatoo,
the palm cockatoo or "palmy".
It's the most intelligent of Australia's,
and possibly the world's, bird species.
Its brain is comparable, in brain-to-body ratio,
to that of a dolphin or great ape.
But it's also a parrot,
and like its relatives,
the palmy nests in tree hollows.
This proud pair have secured a beautiful bough.
And for their entire lifespans, around 60 years,
they will share the parenting.
They pass the baton with a kiss...
..before taking turns to forage.
These birds and this forest have evolved together.
With one of the world's largest beaks,
they are amongst the few creatures able to break into the hard fruits
of the native nonda plum.
As the female returns to the nest, she offers a distinct knock...
[KNOCKS]
..to say, "Yoo-hoo! It's me."
But it is her mate who works harder still to message his partner...
..communicating in a way no bird - indeed, no other animal on earth -
has accomplished.
This male palmy has a talent long thought exclusively a human skill.
He fashions a drumstick
and very deliberately makes music!
Each male produces regular beats to his own particular rhythm.
[SQUAWKS]
Why he does this is still unclear.
Is it a show of strength to ward off competitors?
[SQUAWKS]
Or a message to his partner that she needs to look no further?
He and his nest are best.
A feature of Australia's tropical rainforests is their stability.
But the monsoon region to the west is volatile and unpredictable.
Here, the land seesaws between two extremes -
the floods of the summer's wet season...
..and the raging fires which can take hold,
burning for months through the region's parched winters.
But it's these extremes
which have helped sculpt some of the world's most dramatic landscapes.
One of the largest savannas on earth,
sweeping across one quarter of the continent,
intersected by permanent tidal rivers.
[BIRDS AND INSECTS CALL AND CHIRRUP]
The hunting ground of the saltwater croc.
This male, known to the river guides as Casanova,
has been top croc on this river for decades,
with over 60 pointed teeth.
And while now in his late 50s he might be considered an old croc,
he has learnt a new trick.
Casanova has adapted to the presence of humans in an unexpected way.
He associates the rumble of a boat crammed with tourists
with dinner.
MAN: Life jackets.
They're situated just up there.
I'm not even going to show you how to put one on.
Does anyone know why?
Crocodiles are attracted to bright colours, OK?
And splashing.
So, um... And there's about 5,000 crocodiles in this river.
If you end up in the water, you won't have time to drown anyway.
Yeah? So, number one, avoid going in the water.
But, um, if we do, life jackets are useless.
When not chasing the female crocs,
Casanova puts his natural abilities to good use
and thrills the tourists.
A wavelike thrust created by hundreds of muscles working in tandem
propels two thirds of his body clear from the surface...
..finishing the leap with a bite -
the strongest down force of any animal.
Although it looks unnatural,
crocs will leap for animals on overhanging trees.
He's ready to go now. Look at this.
No mucking around.
Here we go. Here we go. Oh!
Alright.
(TOURISTS GASP) There we go.
Only here in Australia have Casanova and his saltie rivermates
learned to jump for rewards offered up by humans.
To avoid a crocodile attack is very easy.
You stay back six metres from the water's edge
and you never enter the water.
Those two simple things - never get attacked by a crocodile.
Although that is a very complex thing to comprehend for some people.
On this river, human and reptile have found a way to coexist.
Not that life is now easy for the continent's apex predator.
He is relentlessly hunted...
..by the march fly.
Not just here to hitchhike...
..the fly seeks out divots in the croc's armour plating.
Weakness found.
It bores its drill-like proboscis into the soft area of skin below.
A modified form of saliva prevents the croc's blood from clotting.
And then the fly mops up the blood with its fleshy mouthparts,
filling to bursting point on its victim's rich, cold blood.
The delicate three-layered eyelid
is particularly susceptible to attack.
Nostrils are targeted too.
And from this perspective, the menacing croc
is reduced to no more than an involuntary blood donor.
Although he does have one pest control strategy - mud.
Australia's all-natural fly repellent.
Not only a barrier to flies but also a salve to soothe irritating bites.
At least for a moment.
It's not fatal, but it feels like torture.
And despite its ancient evolutionary line,
the croc still has a distinct design fault -
legs so short that there's an itch that can't be scratched.
While the croc is at war with its flies,
the rest of the creatures
who call Australia's northern monsoon region home
battle the extreme variations in climate.
Birds migrate
to cope with the dramatic pulses of the wet and the dry.
Other creatures do not have this luxury.
Unable to move with the seasons, they must stay and face the elements.
On these floodplains in the far north of Arnhem Land,
a creature has evolved a unique coping mechanism
to survive this seasonal change.
The children of Maningrida,
whose playground spans these northern floodplains,
have discovered an extraordinary web of life beneath their feet.
In this one small area, they have helped scientists identify
an astonishing new species of tarantula, or Kidjikarrabba.
Like most spiders, they have eight eyes and eight legs
but what sets these tarantulas apart is their dashing red coat.
And fangs long enough to dig deep into flesh.
The floodplain is pockmarked by thousands of spider burrows -
a megacluster of ambush hunters.
The female will spend hours waiting motionless
for the perfect dinner guest.
She has laid silk out around her burrow entrance.
It's a carpet of trip wires.
Once in the tarantula's vicelike grip, there's no hope of escape.
She deals a final blow, injecting it with toxic venom.
The grasshopper is paralysed.
Her last catch for the dry season.
[THUNDER RUMBLES]
Rumbles outside suggest her world is about to be inundated.
The monsoon has arrived.
Thunderheads reach over 12,000 metres high.
Electric charges begin to spark and fire.
A thunderstorm producing the equivalent energy of an atomic bomb.
[THUNDER CRASHES]
A flood makes its way towards the plain.
For a creature that lives underground,
this can only spell danger.
But she is no ordinary tarantula.
She won't flee her burrow as the watertable rises.
She has her own silvery life support system.
Her hairy coat traps air bubbles.
Keeping movement to a minimum,
she can survive on these tiny air pockets.
Like an astronaut in space, she has created her own atmosphere.
Known only as the diving tarantula, their discovery is so recent,
they are yet to be officially named by science.
By the peak of the wet season,
this area will be under half a metre of water
and, with nowhere to go,
it's assumed she'll remain submerged for the next four months.
Scientists estimate there are 25,000 diving tarantulas
on this floodplain -
the highest concentration of tarantulas anywhere in the world.
Most certainly this is no place for an arachnophobe,
or even a family holiday.
As the wet season departs the Top End,
it leaves behind a vivid savanna, plumped by the rain.
Now it will be the dry season's turn to repaint the landscape.
But before the greens turn brown, they will be dressed in black.
200km south of Maningrida,
the Indigenous rangers of Central Arnhem Land
are setting the ground alight.
They burn now
to prevent uncontrollable wildfires later in the season.
The crisp grass ignites quickly.
The flames move on, leaving the trees intact.
And as the smoke builds, the rangers know to look skyward.
They will almost always see a black kite overhead.
As the grass burns,
a mass exodus of creatures is forced to flee the heat.
So the black kite, precision instrument that she is,
can swoop on parbaked bugs.
But the kite doesn't feast alone for long.
As the smoke builds, so do the kites, arriving from kilometres around -
hundreds of them.
All are competing now for the spoils.
Squabbles break out. Talons clash.
The traditional owners know what this bird might do next.
For thousands of years, Dreaming stories have been told
of a bird that makes its own fires.
The clever Firebird, or Karrkkanj.
The only creature other than humans
known to harness fire for personal gain.
The kite has been witnessed building new fires to flush out more insects,
creating new hunting opportunities.
And despite being the world's most common raptor,
it is only Australia's kites which do this.
Rangers are left to deal with extra fires
while those guilty of fueling the flames fly free
and are very likely to reoffend.
For tens of thousands of years,
Indigenous people have been telling the stories
of this ancient land and its creatures...
..and yet there is so much about Australia's wildlife
that remains unknown to the world beyond.
About the intelligence...
..the resilience...
..and the perseverance of these unique and irreplaceable creatures.
Some are thriving...
..while others are on the edge.
Australia may be an ancient land
whose creatures have grown over millennia
from her rock, soil and flora...
..but human change is shifting everything.
What this means for the future of Australia's animals
is another story again.