Into the Wild New Zealand (2022) s01e05 Episode Script

Creepiest Crawlies

The isolated
islands of New Zealand
are famed as an unusual paradise
where strange birds evolved
in isolation, unique reptiles
have survived since the age
of the dinosaurs, and
legions have found a haven
in and around its coasts.
But look a little
closer, and a new world
emerges, a land of
miniature monsters,
lilliputian predators,
and tiny terrors.
If you look into the dark
undergrowth of this island
paradise, you'll find
drama of a different scale
With "wildest New
Zealand's" "creepiest crawlies."
A magical glow
illuminates the night.
The mesmerizing lights in a dark
ravine seem to draw you nearer.
And that is exactly
the idea, because
behind the beautiful glow
lies the ugliest of killers.
This is the larvae of
the fungus gnat fly,
known locally as glow worms.
The magic of their
is just the center of
their web of deceit.
Around them hang
glistening gossamer
strands, another delicate
beauty that belies a deadly intent.
These are fishing
lines, cast out
to ensnare the unsuspecting.
The glow worm
turns on its light,
the chemical reaction powered
by an enzyme called luciferase.
And it certainly has
a devilish purpose.
Insects are drawn
to the light, believing
they are the distant
stars they use to navigate.
The fishing lines snag the prey.
The vibrations
alert the glow worm.
But this small fly is not enough
to take the glow worm's fancy.
It wisely waits for more.
A hoverfly.
Its stripes mimic a
wasp, but it's harmless.
Predator and prey are
more evenly matched.
But the fly is at
the worm's mercy.
The fisherman reels
in its line and sucks
out its victim's juices.
During this juvenile
stage of its life,
the glow worm must
eat as much as it can,
enough to see it through
its brief life as an adult fly.
For up to nine
months, the glow worm
lays out its traps each night.
Each line can take
15 minutes to make,
and it might lay up
to 25 of the traps.
At the end of the night,
it will ingest the lines
to reabsorb their nutrients.
Nothing goes to waste
in this dank ravine
at the bottom of the world.
New Zealand sits alone
in a vast ocean, an isolated
island chain 1,600 miles long.
It's home to an incredible
diversity of habitats.
The south dips its toe in
the frigid southern ocean,
while the far north
is subtropical.
Here, the year round
warmth and high rainfall
make the perfect environment
for creepy crawlies to run riot,
Creating an intricate web of
predator-prey relationships.
Here, a true master of
disguise hides in plain sight,
a New Zealand praying mantis.
Few insects are better
designed hunters.
It has evolved a body, shape,
and color that helps it blend
in with its leafy surroundings.
It holds its raptorial
forelegs tight against its body.
These are deadly weapons,
edged with dagger-like spines
that must be kept clean.
Its wide-set compound eyes
give it excellent binocular vision.
And most valuable, its
specially adapted neck.
It can turn its head 180
degrees, a useful tool
for spotting dinner.
Today's victim, a bottle fly.
It moves into position,
silently stalking forwards.
As if it didn't blend in
well enough already,
it gently sways to
mimic leaves in the wind.
Unaware of the
approaching assassin, the fly
innocently goes
about its business.
For the mantis,
timing is everything.
It's over in a split second.
It grasps the fly in a
vice-like grip and eats it alive.
Its appetite is enough
to take in 25 flies a day.
All the better for the
hunter that is now stalking it,
a green and golden bell frog.
For this frog, the fatter
the victim, the better.
The green and golden bell
frog was brought from Australia
to New Zealand in the 1860s.
Since then, it has spread
across the far north.
But while the bell
frog stalks the mantis,
an even more formidable
frog is stalking it.
At nearly four inches,
the southern bell frog
is the largest frog
in New Zealand.
Its call has earned
it the nickname
of growling grass frog.
But today, it remains quiet.
The silent hunter is a
predator of other frogs.
Somebody is going to
be eaten today, but who?
A locust offers itself
up as the prize
Saving the mantis and
the green and gold bell frog.
Elsewhere, another Australian
immigrant forages on the forest
floor, a plague skink.
introduced in the '60s,
it's the only exotic lizard
to successfully establish
a population in New Zealand.
Sometimes called the
rainbow skink because
of its colorful,
iridescent sheen,
it's an opportunistic
It searches through
the leaf litter,
uncovering small
caterpillars to eat.
Growing to one and a half
inches long with a tail that can be
one and a half
times longer, it's
larger than most
of its invertebrate
prey on the forest
floor, which automatically
puts many bugs on its menu.
But there's one creepy
crawly large enough
to send shivers down
the skink's spine,
The giant centipede.
In New Zealand, they can
grow nearly eight inches long.
South American species
may reach over 23 inches.
The colossal centipede
carefully coordinates its legs
in a wave-like
motion, enabling it
to almost glide over the
leaf litter on the forest floor.
Lacking eyes, its long,
segmented antennae
help it to sense its
prey's movement.
The skink freezes, but the
predator's antennae are also
capable of detecting smells.
And the ill-fated
skink is discovered.
The giant centipede
wraps the length
of its body around the
skink, using its many legs
to hold its prey in place.
Behind its head,
its first pair of legs
is modified to
function like jaws.
They end in a
sharp pair of fangs
that inject the skink with a
powerful paralyzing agent.
It eats its fill and discards
the half-eaten body.
The centipede's flattened
shape has evolved to help it hide
and rest under logs and rocks.
It returns to its
cool, damp lair
until it is time to hunt again.
Over 150 miles
south lies Auckland.
The largest city in new
Zealand, a bustling subtropical
Metropolis where steamy
summer days can top
out at 86 degrees fahrenheit.
Despite the urban
sprawl, there are
still many pockets of forest
dotted throughout suburbia.
For small-scale creatures,
these nooks of nature
may as well be in a
vast, remote wilderness.
It's early morning, and a
giant relative of the cricket,
known as a weta, emerges
in search of a mate.
Only found in New Zealand,
there are over 100 species of weta.
They occupy
almost every habitat.
This species is known
as the Auckland tree weta,
but it can be found
throughout the north island.
It can grow to one
and a half inches long,
and is mostly arboreal.
Like many insects, weta can
use several different methods
to communicate.
One is smell.
He's following a female's scent.
She may even be releasing
pheromones to attract him.
She'll likely be in one
of the many Burrows
bored into the tree.
His long antennae, almost
twice the length of his body,
are sensitive chemical
detectors equivalent to noses,
though a lot more movable.
He can also detect
the smell of volatile oils
that the tree uses
to heal its wounds,
an additional guide to the
location of the many Burrows.
But he also has
extremely sensitive hearing.
Like many insects,
his ears are small disks
located on his front legs.
Wetas can signal
each other by making
telltale rasping
sounds with their legs,
so he's listening for her too.
But he is about to have company.
Another male has
detected the female's
scent, picking it up
on the gentle breeze
of the forest floor.
Male wetas are
ferocious combatants
when it comes to females.
They have larger heads,
equipped with a pair
of oversized mandibles used
for fighting over mating rites.
He can give a painful bite.
There's movement
in the branches above,
an early bird that's
found more than a worm.
He raises his sawtooth hind
legs over his body in defense,
ready to strike out.
But this bird wants an
easy breakfast, not a fight.
There's another insect
in these trees that
might be more to its taste.
The Burrows the
weta live in were
made by puriri caterpillars.
Growing nearly four
inches long, puriri caterpillars
are tunnel boring
specialists, perpetually
expanding their home.
As it eats the surrounding
soft cambium layer of the tree
that lies under the back,
it grows bigger and bigger.
So it's continually
boring the tree to fit
its ever-lengthening body.
The stage of the puriri's
life can last a remarkable five
years, if it makes it.
The largest
caterpillar in the forest
would be a prize
catch for a hungry bird.
This caterpillar
takes the risk as it's
about to begin the biggest
transformation of its life.
Its creamy color
shows it's near bursting
with the fats it'll need for
a fast of up to six months.
The web and
sawdust it's building
around its burrow entrance
will eventually form a cap.
Sealed safely inside, it'll
gradually metamorphose into new
Zealand's largest moth.
On a neighboring tree, the
empty husk of a puriri caterpillar.
It's completed
its transformation.
And after five years of
living in its wooden burrow,
it has emerged as a vibrant
green giant, the puriri moth.
They're known to the native
maori people as the ghost moth,
because they're
believed to be the spirits
of ancestors returning
to visit their descendants.
It's the largest moth in New
Zealand with a wingspan
almost six inches across.
Before he can fly, he
must first pump himself up.
Newly hatched
butterflies and moths
need to increase
their internal pressure
to form their hard
exoskeleton and to make
their wings rigid for flight.
His green wings
identify him as a male.
Females show more
brown in their coloring.
With no functional mouth
parts, his sole purpose in life
is to find a mate and
breed before he dies.
His short antennae
will unerringly
guide him toward
a female, following
her trail of pheromones.
But his inaugural
flight might be his last.
The forest floor below
is a dangerous place.
A Norway rat lurking, one of
three species that live here.
Found on every continent
except Antarctica,
these rats are not
native to New Zealand.
They were introduced by
the first European settlers
in the 18th century,
and have flourished.
Catching a whiff of the
moth, the rat follows its scent
across the forest floor.
Puriri moths have
short lives at best,
but this one's life has
been cut even shorter.
With almost no native mammalian
predators to compete with,
rats quickly fill that niche,
devouring much of new
Zealand's native wildlife.
It polishes off the
moths' protein-rich body
and discards the wings.
There's another introduced
species here that's more
constructive than destructive.
The paper wasp
Their papier-mache
nests are made
from plant fibers and saliva.
Each nest is started
by a single female,
but unlike other wasp
species, she's not a queen.
Paper wasp hierarchy is divided
into workers, who gather food,
expand the nest,
and raise the young,
and gynes who lay
eggs and start new nests.
The gynes function as
leaders for all the workers.
They mostly communicate
with each other through smell.
Inside the hexagonal
paper cells,
larvae hang upside
down, waiting for an adult
to bring them food.
The gynes have direct
influence on each larva's destiny.
By rhythmically
drumming on the cell walls,
it appears they can cause larvae
to develop as workers instead
of gynes, adjusting
the population balance
according to the nest's needs.
Repeated tapping
at 17 times a second
seems to influence how
fat the larvae become,
which then determines if
they grow into a worker or gyne.
The fattest larvae become gynes.
When close to maturity, the
larvae cover their paper cells
in silk and emerge a week
later as an adult, ready to take
on the family responsibilities.
When the sun goes down, a
different world comes to light.
The creepy crawly
night shift takes over.
A female tree weta ventures
out of her burrow to forage.
She's browsing on a diet
of soft leaves and shoots.
She's not alone here.
A male tree weta
has followed her,
and he has only
one thing on his mind.
He probes her tentatively
with his antenna,
part of the courtship ritual.
But she appears more interested
in her dinner than the much
smaller courting male.
Undeterred, the
male tries again.
He gently taps her
with his genitalia,
at second base in
the mating process,
and his persistence pays off.
Maneuvering into
position, he hangs
underneath her, inserting the
end of his abdomen into hers.
Their mating lasts for a
brief minute and a half.
Then she leaves him.
She'll use the long
appendage at the end
of her body called an
ovipositor to lay her fertilized
eggs in the soil.
She won't stay to
see her offspring,
and she'll only be
able to lay one more
brood in her two-year lifespan.
The tree weta is the most
widespread of all the wetas.
Its range extends deep
into the south island.
More than 300 miles
south of Auckland
is kahurangi national park.
It's a place of primordial
forests and animals,
the oldest part of New Zealand.
The park sits in the northwest
corner of the south island.
This 1,700-square-mile refuge
is where ancient New Zealand
lies untouched and protected.
In a quiet forest stream
in the kahurangi forest
lives a freshwater crayfish,
known to the indigenous maori
as koura.
This is a north island
species, but its range
extends into small pockets
here at the top of the south island.
This koura is a stream
dweller, but they can also
be found in lakes and ponds,
growing to nearly three inches
The koura belongs
to an ancient lineage
with close relatives in
Australia and South America,
descendants from a
land called gondwana
when the southern continents
were merged as one.
Normally nocturnal,
the kahurangi forest
provides enough
shade in the day for it
to leave the safety of
its home and head out on
important business, breakfast.
A professional scavenger,
it's not fussy about what it eats.
Today, the koura's lucky.
A drowned forest cricket,
one of its favorite meals.
Large claws grip
the meal while two
small legs called
maxillipeds pull
food scraps into the mouth.
Smaller still, tiny
white appendages
called Gill bailers beat
to create a flow of water
over the animal's gills.
Decapods like crayfish,
lobster, and shrimp
have this unusual
respiratory system.
The Gill bailers draw a steady
stream of oxygenated water
in at the base of
their legs, forward
past their internal gills,
and out through their mouths.
The Gill bailers create
this current in otherwise still
As it devours the cricket,
the scent of the meal
drifts, attracting attention
from other crayfish.
Watching from above, dolomedes
aquaticus, a water spider.
With a length of nearly
six inches, she's a female.
The males are much smaller.
She isn't interested
in the koura's meal.
Like all spiders, this
hunter catches live prey.
No web traps for her.
She anchors herself to
the rock using her back legs.
She weighs less
than half an ounce,
and her legs
distribute that weight
widely across the
water's surface, which
will let her walk on water.
She waits, feeling
for the vibrations that
reveal prey is swimming near.
A cricket floats into range.
She injects the cricket with
a toxin that immobilizes it.
Disturbed, she dives to safety.
Her silvery glint is
actually a thin envelope
of air covering her body,
trapped in the fine hairs
of her exoskeleton.
The air covering her eyes
acts like a diver's mask
so she can see underwater.
And she can breathe the air
trapped around her abdomen,
a whole body aqua
lung that lets her stay
submerged for up to 30 minutes.
And when the coast is
clear, she returns to her seat
on the rock and her fishing.
Meanwhile, the
koura has retreated
to the shelter
of its burrow so it
can continue its meal in peace.
But that doesn't stop the
nosy neighbors from inviting
themselves around for a bite.
Koura are cannibals.
Smaller koura are fair game,
as are sick or molting crayfish.
It uses its large,
pincer-like claws,
called keeli, to defend
itself, and chases
away the unwelcome visitor.
Its claws are so important
that when a crayfish loses one,
they put body growth on
hold until the pincer has
grown back.
This time, it keeps
its meal all to itself.
Elsewhere on the river,
aerial insects thrive.
New Zealand has
41 species of bee.
28 of them are native.
But these are wild
European honeybees,
now a global species.
The massive inflorescence of
the New Zealand cabbage tree
is a valuable nectar
source for this colony.
The cabbage tree
flowers early in the spring
and continues
throughout summer, so it
will be a staple for these
bees for many more months.
And the bees are a staple too.
On a nearby bush
lie the cast-off skins
of giant dragonfly nymphs.
They have crawled up from
the water's edge below to set
themselves free as adults.
Growing to over
three inches long,
New Zealand's giant
bush dragonfly is
a highly capable aerial hunter.
Its twin pairs of black gossamer
wings, over five inches wide,
make it extremely maneuverable.
Its giant compound eyes
provide all-around vision.
These skilled flyers
hunt on the wing,
snatching their
prey from the air.
They successfully catch as much
as 95% of the prey they target.
They can eat on the
wing too, but will also
land on a favorite perch
to consume their meal.
The dragonfly's mouth is
equipped with the equivalent
of serrated shears, allowing
it to easily butcher the bee.
It will hunt every day, almost
nonstop, for the two months
it is an adult. And then it will
lay its eggs on the riverbank
below, and the
cycle will begin again.
Over 600 miles further south
is New Zealand's fiordland,
the bottom of the country,
a place riven by glacier cuts,
sounds, and valleys, cloaked
in dense, temperate rainforest.
Staring into the moor
of the furious winds
the sailors called
the roaring forties,
it rains in fiordland
200 days of the year,
delivering a phenomenal
500 inches of precipitation.
Snow can fall any
time of the year.
Despite the cold of
the early morning,
the rich undergrowth
is a fertile
haven for Hardy insects.
This male longhorn
beetle, called a huhu,
has just emerged.
He has only a couple
of weeks to live,
so he's in a race to find a
mate before his time is up.
During his short life,
he won't feed at all.
His sole purpose
is to find a female.
He uses his flexible antennae
to help him navigate as he makes
his way onto a sunny perch.
About the size of an
adult human thumb,
they're the largest
beetles in New Zealand.
His hardened wing
covers, known as elytra,
protect his hind
wings and abdomen,
but they're also heavy,
making it that much harder
to get airborne.
Even after take-off, he's
not quite ready for flight.
It'll take a few more short hops
before he's truly warm enough
to fly for minutes at a time.
As he prepares
to fly again, he's
unaware he has an audience.
A morepork is watching
him with interest.
The small, native,
spotted owl is commonly
found in New Zealand's
temperate forests,
hunting from dusk till dawn.
The huhu will make a fine
meal at the end of a busy night.
The owl's diet is broad.
Insects, small mammals,
even other birds.
But longhorn beetles like
the huhu and ground dwelling
beetles of the scarab family
can make up almost half its food.
In the rotting wood on
the damp forest floor,
grubs of the huhu
beetle tunnel their way
through the soft timber.
These grubs will spend up
to three years boring through
the wood, eating it as they go.
They a part of nature's
extensive waste disposal team.
The labyrinth of
passageways they excavate
with their strong jaws will
accelerate the wood's decay
and return it to the
soil as nutrients.
The colored spots along
the length of their body
are the spiracles through
which they breathe.
As they digest the timber,
they expel the remains
in little pellets behind them.
Wood is no easy meal, but
they have as many as 1,800
different types of
symbiotic bacteria
in their stomachs to help
them digest the roughage.
This is one time when having
a tummy bug is a good idea.
Growing nearly
three inches long,
the grubs are considered a
delicacy by New Zealand's
native maori people, and
are said to taste like peanut
butter when eaten
raw, a flavor for which
another inhabitant of the
forest has developed a taste.
The small
spine-covered hedgehog.
Introduced to New
Zealand in the late 1800s,
it's thrived on a diet
of native species since.
A nocturnal forager, this female
can travel more than a mile
a night in search of a meal.
Following her sensitive nose,
she discovers an appetizer
to start the night.
She savors the grubs' fat,
juicy bodies, full of protein.
She needs to gain weight
to store insulating fat
during summer,
enough to last her
through hibernation across
three freezing winter months.
One is never enough.
She moves off into the
forest to search for more.
From gentle giants and
awkward lovers to skilled hunters
and masters of disguise, a
journey into the undergrowth
reveals life on
a different scale.
New Zealand's isolation
has allowed these giant
invertebrates to flourish.
Weird and wonderful,
these unsung heroes are
New Zealand's
creepiest crawlies.
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