All language subtitles for Sky Hunters The World Of The Dragonfly 1080p HDTV MVGroup EN Sub

This is one of the most successful
lifeforms on our planet,

they existed 100 million
years before the dinosaurs.

They're skilled at aerobatics,

and they're merciless predators.

Their appearance and their
life-cycle is so strange,

they could be visitors from another world.

These are the dragonflies.

Science has given them colorful names,

broad-bodied chaser,

four-spotted chaser, scarlet dragonfly.

Some glimmer like liquid metal,

others seem to be fashioned out
of stained glass or enamel.

These are creatures that
have barely changed

in hundreds of millions of years.

From the very beginning, they
have been perfect sky hunters.

In 1558, the French naturalist
Guillaume Rondelet,

noted a distinct resemblance
between the hammerhead shark,

and a small insect.

The first mentioned in
scientific literature

of dragonflies, and the
smaller damselflies.

Their habitats are just as
varied as the forms they take,

but they always have to
be close to fresh water,

that plays a vital part
in their life cycle.

All dragonflies are excellent fliers,

but they fly in different styles,

the smaller damselflies
tend to be more cautious,

they're not known for daring aerobatics,

or sudden swooping attacks.

They move in a graceful, weightless ballet.

Big dragonflies look like
marauding fighter planes,

they patrol their territory
at more than 50km an hour.

They hover like a helicopter,

and dart off at top speed
from a standing start.

They beat their wings so slowly,

only about 30 flaps a second,

we don't hear a hum or
a buzz, but a sizzle.

Their body design makes
them perfect predators,

300 million years of evolution
have given them the tools

to devour any insect prey.

They wait at raised observation points,

on the lookout.

They hunt anything they can overpower,

that includes flies, wasps, butterflies,

even their own species.

Dragonflies have a well-earned
reputation as cannibals.

Wherever there's water, there
are not just dragonflies,

but also potential prey.

A dead fish on the river bank
attracts an army of flies.

Within a few days, their maggots

will have consumed it from the inside,

But these blue bottles
leaping on and off the body,

are being watched by a female darter.

Her razor-sharp mandibles consume
the best parts in minutes.

The bigger species need plenty of nutrition

to provide energy for
their powerful bodies,

and there's no shortage of larger prey,

such as butterflies.

In some places, for
instance, on Greek islands,

there are real mass gatherings of moths,

like these jersey tigers.

Jersey tigers tend to
gather near water sources,

and that's also the perfect
habitat for dragonflies.

But even in ordinary fields,

species like the peacock
butterfly are anything but safe.

Even big moths are quickly consumed,

this one will soon be gone.

Scientists have been collecting dragonflies

since the 18th century,

but there's always been a difficulty,

dragonflies quickly become deathly pale,

they lose all their color.

That's why collectors
have usually preferred

to concentrate on butterflies.

They're more colorful,

and don't lose their pigment when they die.

The reason is, that their wings are covered

in colored scales.

The scales lie on top of
each other, like roof tiles,

many shimmer brightly, depending
on the angle of the light.

Of course, there are exceptions,

the wings of the glass moth
have very few color scales,

they look a lot like the
transparent wings of a dragonfly.

Dragonflies are found on all continents,

their flying skills are astonishing.

At the end of the middle ages,

humans set out to discover new continents,

dragonflies were way ahead of them.

Some have been found in mid-ocean,

550 kilometers from land.

They can fly from Libya
to Iceland in four days.

With the wind behind them
their speed has been measured

at more than 130km and hour.

Many dragonfly species are
based in the tropics,

in South and Central America,

there's no shortage of fresh water,

and long stretches of
swamps and rain forest.

Hundreds, perhaps thousands
of dragonflies species

are still unknown to science.

Dragonflies stand out, many other
animals in the rain forest

notice them, even if they
aren't on their menu.

Capuchin monkeys are very observant,

and flitting dragonflies are a
good source of entertainment.

Dragonflies are found
in equatorial regions,

right around the globe.

Of course in East Africa,

the big animals are more
conspicuous and more popular,

easy to forget that dragonflies
have lived in Africa

for so much longer than the great mammals,

they were here long
before there were rhinos,

giraffes, or elephants.

Dragonflies have settled in
the most inhospitable places,

like the Sahara.

Dragonflies have something vital in common

with human civilization,

both depend on fresh water.

This ancient civilization flourished thanks

to the River Nile.

Its papyrus marshes have always offered

a home to dragonflies.

The ancient Egyptians worshiped their gods

in the form of animals.

Insects also played an
important role for them,

3,400 years ago they
immortalized dragonflies

in their tombs.

We human have four million
years of history,

a history we know so little about.

Dragonflies are 80 times as old as we are,

they originated an astonishing
320 million years ago.

In those distant times,

there was just one single,
super continent, Pangaea.

At that time, the greatest variety of life

was in the waters of the ancient
oceans where life began.

Some of the most complex
creatures, were the crustecea.

Transparent jelly fish too,
swam in both the oceans,

and the coastal regions.

But it would take considerable longer

before life could establish itself on land,

The conquest of the land by
plants was a slow process.

About 330 million years ago,

evolution came up with something new,

forests covering huge
stretches of the earth.

In the carboniferous,
fern and club moss trees

covered wide areas.

Horsetails grew up to ten meters.

But these jungles contained
relatively few animal species.

Fish breathing through lungs,

had made the move from water on to land,

becoming primitive amphibians.

And there were giant scorpions,

as well as huge spiders,

and two meter long,
multi-limbed arthropods.

But the ferns forests
concealed other giants,

the ancestors of today's dragonflies.

Even 300 million years ago,

their body plan was so perfect,

that it has barely changed
since, except in size.

The giant dragonflies of the carboniferous

had a wing-span of more
than 70 centimeters.

It was a time of permanent,
geological change,

when the earth eroded and shifted.

If a dragonfly died without
being eaten by a scorpion

or some other creature,

there was a good chance
it would be preserved.

Quite quickly it was buried
in sand and other materials.

Geysers and mud often did the rest,

before long, the body would
be completely covered.

The makeup of the earth
and the lack of oxygen,

hindered decomposition.

The mud deposits turned
into a time capsule.

For over hundreds of millions of years,

the organic layers turned to stone,

and their contents to fossils.

But although the dragonfly's
bodies left perfect imprints,

all we have from the carboniferous period,

are traces in relief.

About 200 million years ago
in the Triassic Period,

the world got a new look.

Giant ginkgo forests now covered
large parts of the earth.

But the Triassic also brought
a revolution on land animals,

the first dinosaurs arrive
on the evolutionary scene.

They will rule the earth
for 170 million years.

Resin seeps out of wounds in
the bark of the ginkgo trees,

slowly the viscous fluid oozes down,

dripping off leaves on to the ground.

Everything this sticky, glutenous
fluid touches is doomed.

In places, resin flows like lava,

trapping tiny particles on its way.

When dragonflies come into contact with it,

their delicate wings
can't help them escape.

More and more resin lands on them,

until the dragonfly is completely covered.

Perfect, airtight conservation.

This million year-old resin survived

to be washed up on the shores of the Baltic

and the Caribbean.

We know it as amber.

And very often, there's
something trapped inside.

These ancient prisoners are
proof that dragonflies

have barely changed over the ages.

And the reason that time has had no effect

on the shape of the dragonfly,

is that its body design
is virtually perfect.

Its entire body is covered
in armor made of chitin.

The most notable feature is its head,

It's dominated by two gigantic eyes,

but they work quite
differently from a mammals.

Each eye is composed of up
to 30,000 honey-combed eyes,

forming a hemisphere.

These compound eyes give
almost 360 degree vision.

Dragonflies probably see
better than any other insect.

But the most amazing
thing about dragonflies,

are its two pairs of wings,

they're constructed around a network

of lateral and longitudinal arteries,

a transparent, parchment-like membrane

is stretched between them.

A thin, waxy sheath
creates the lotus effect,

preventing particles of
dust sticking to the wings.

Dragonflies are fast, tireless fliers,

they quickly open up new territories.

A dragonfly on a reconnaissance flight

can reach a height of
several hundred meters.

Areas of reeds, have an
almost magical appeal.

But often, the best habitats
are already occupied

by other dragonflies, and they
will defend their territory

against any intruder.

Dragonflies know only
the lore of the strong,

a battle for supremacy is inevitable.

The aim is to repulse the enemy,

the end, often sees the loser
falling into the water.

If it falls in deep enough,
it won't get out again.

The European pond terrapin
has remarkable eyesight,

these carnivorous reptiles

are not going to let a
drenched insect get away.

In spite of all these losses,

enough dragonflies escape for
the survival of the species,

their complicated mating process
is an ancient inheritance,

unique in the natural world.

The male grips the female behind its head

with pincers at the end of its abdomen.

The female twists her lower body forward

to unite with male's semen sack

on the underside of his abdomen.

The unusual position that results,

is known as a mating wheel.

The male's grip can last several seconds,

or as long as an hour.

All dragonflies, and the
smaller damselflies,

form the mating wheel.

Many damselflies stay connected
while they lay their eggs,

this usually takes place in the water.

The females poke their
abdomen under the surface

to deposit their eggs on
water plants or leaves.

All this time, the male
still clasps the female

behind her head.

At good locations eggs
are often laid on mass,

dozens of couples gather.

They call these couples tandems,

because they fly around in this position.

Many female damselflies dive under water

to attach their eggs to the plants.

They can stay down for up to 90 minutes.

These meadow hawks have
a different strategy,

males and females stay
united in their tandem,

and individually tap their
eggs onto water plants.

In some species of dragonfly,

the female lays her eggs alone.

They choose a variety of places,

sometimes on the water's surface,

and other times they stick their abdomens

deep into the water to place their eggs.

But not all dragonfly
species lay their eggs

directly in the water,

some hide them in moss
cushions or between stones.

Rain showers will
eventually will eventually

flush the eggs into the water.

The number of eggs varies between species,

from as little as 50, to several thousand,

but they are all tiny.

The biggest measure hardly
more than half a millimeter.

Central Europe has more than 200

different species of willow,

they're typical of wet zones.

They grow next to ponds,

in water meadows, or along
the banks of streams.

When they blossom in spring,

we know their flowers as catkins.

But in the middle of summer

they attract a very unusual insect,

and demonstrate an ingenious
survival strategy.

The willow emerald damselfly

lays its eggs directly in willow bark.

When this happens, the male and female

are usually still joined in tandem.

Each couple can lay up to 200 hundred eggs.

For the parents, that's
the end of the matter.

Deep inside the bark,

the clutch of eggs survives the winter.

Snow and freezing cold
make little impression.

By the following year in the
springtime, they're ready.

Months later, after the catkin blossoms,

tiny creatures emerge from the rind,

these are the micro-larvae.

If they're lucky, they
fall straight into water.

Where there's water, there's life,

even at a man-made source
in the middle of a city.

Hooded crows enjoy the bubbling waters,

not just as a drink, but
also as a refreshing bath.

So it's not surprising if
dragonflies are found here too,

whether in the country or in town,

dragonflies often find their way

through and open window into a building.

Maybe even into the Natural History Museum.

For this lost insect,

it's a journey millions
of years back in time

when dinosaurs ruled the earth,

and were part of the dragonfly's
everyday experience.

Thunderstorms, a natural phenomenon

most dragonflies experience,

because most are active
in early and mid-summer

When the sky darkens many stop flying

and look for places to rest,

they'll most like spend the night here too.

Dragonflies are well protected

from most environmental influences,

rain doesn't usually worry them.

Thanks to the lotus effect,

raindrops just slip off their wings.

But sometimes storms become real downpours.

With the cooling effect of the rain,

dragonflies lose their strength,

and many can no longer hold on.

If they land in the water, it's all over.

And when the sun comes out again,

there's a feast on offer.

Frogs aren't the only animals

that snap up dislodged dragonflies,

ducks too, happily scoop
up a dripping morsel.

But most of the dragonflies
survive the storm unharmed.

Dragonflies have two lives,

they spend one of them
as a virtuoso aviators,

the other is lived in secret, under water.

The dragonfly eggs have turned into larvae,

their body plan seem strange,
even extraterrestrial.

Damselfly larvae have slim bodies,

with rudder blades at the end,

these are covered with
fine tracheal systems

that function like lungs.

Damselfly and dragonfly larvae

can live in water for
many months, even years.

But they already have two things in common

with adults of their species,

their great, compound eyes and
their predator's instincts.

Dragonfly larvae eat worms and fly larvae,

but also vertebrates,

tadpoles small fish are on the menu too.

Their potential prey may
be many times their size.

Dragonfly larvae can be
several centimeters long.

When they spot their prey,
they creep towards it,

once the victim's in range,
they act with lighting speed.

They have an extension to their lower jaw

that can shoot forward in 20 milliseconds

grabbing their quarry and
dragging into their mandibles.

There, it's dismembered and eaten alive.

This unique method of catching
prey has inspired the design

of many a Sci-Fi alien in the movies.

It may seem brutal, but it's no different

from the way a lion or a
hyena kills its victim

and tears them apart.

After several months or for
some species several years,

the dragonfly larvae final move on.

Usually by climbing reed
stocks, or swamp plants.

It's time for the great metamorphosis

that turns a larva into a dragonfly.

Pressure builds up inside the body,

until the larva's skin bursts,

and the shriveled dragonfly emerges.

It pumps blood into it's
wings and around its body

to reach its final form.

This process can take an hour or more.

When its chitin carapace has hardened,

it begins to shiver itself warm,

before taking its maiden flight.

The only memento of it's early form

is the larva's abandoned skin, the exuvia.

Sometimes, so many dragonflies
hatch at the same time,

they make a swarm.

Depending on the species,

they will separate almost at once,

or fly hundreds of kilometers together,

often towards the Mediterranean.

But many dragonflies die,
almost as soon as they hatch.

There are bird species that specialize

in hunting large insects.

Like bee-eaters.

These brightly colored birds breed in holes

in mud cliffs, and their young
are permanently hungry.

They don't only hunt stinging insects,

they're especially fond of dragonflies.

Bee-eaters like to catch
their prey in mid-air.

If they see a dragonfly,
it has little chance.

Every day, dozens end up
caught in these sharp beaks.

These dangerous enemies are
found close to water, spiders.

Even with their excellent eyesight,

dragonflies can't spot their webs.

In the breeding season,
losses are especially high.

The wasp spider is a very
successful dragonfly hunter.

The first bite paralyzes this damselfly,

then the spider wraps it up like a mummy.

Its fate is sealed,

It's now a ready meal to be eaten later.

But spiders aren't the only enemy

in thick vegetation of the riverbank.

Praying mantises are just as dangerous.

They are lighting-fast hunters,

pitiless eating machines.

But then dragonflies are
really no different,

one predator vanquishes another.

But all these daily loses won't threaten

the survival of the species.

Fast-flowing rivers and streams

don't seem to be the ideal habitat

for delicate dragonflies, at first sight.

If there's enough greenery
on the riverbanks,

this is where you'll find some of the most

beautiful damselflies, the demoiselle.

In contrast to other species,

their wings are not transparent but shimmer

in metallic blues and greens.

And their flying style is quite
different from the others,

they don't zip from place to place,

but flit graciously, like a butterfly.

It can only be appreciated in slow motion.

Demoiselles have a wing-span
of around seven centimeters.

There are two kinds, the
beautiful demoiselle,

and the bandit demoiselle.

They live in similar habitats
and show the same behavior.

These are social insects.

They often flock together in large groups.

Riverbank plants now become very important,

serving as lookout posts.

Demoiselles have a highly
developed sense of territory,

the males sit on the most
exposed twigs and leaves,

after a patrol, they always
return to the same place,

and then they start a
rhythmic wing clapping.

Experts think this is a
form of communication

within the group.

A male demoiselle has only one priority,

to impress a female so he can mate with her

and so guarantee the
survival of the species.

It' hard to find wetlands

that are completely untouched by humans.

Spring fens and low moors
are relatively unspoiled.

This mossy, swampy terrain
with its puddles and ponds

is irresistible to dragonflies.

This is where the Southern skimmer lives,

a rare species that needs a warm climate.

This bright, blue dragonfly was discovered

relatively recently by science.

The first description dates from 1837.

An anonymous-looking plant
often grows among the moss,

the edges of its green,
fleshy leaves turn upwards

to make them look like a canoe.

This is the butterwort.

This inconspicuous plant
is deadly to insects.

The soil here isn't nutritious,

so the butterwort compensates
by catching insects.

Its leaves are covered
in tiny, sticky drops.

Deadly traps for dragonflies.

At the same time, the plant
secretes a digestive fluid.

The dragonfly is slowly dissolved,

and the butterwort absorbs the nutrients.

Hill moors are an even
more extreme habitat.

Carnivorous plants are everywhere,

the round-leaved sundew is
the best-known of them.

These glistening droplets look so inviting,

like dew or nectar,

but they're sticky, and if any insect

comes into contact with them

it usually can't get away.

Bigger prey like dragonflies are overcome

by several parts of a
plant working together.

If the insect struggles,
more liquid is secreted.

This damselfly desperately tries to swallow

the plant's secretion, but it won't help.

The sundew's digestive enzyme

simply get into the damselfly's body

and dissolve it even faster.

Near the end of a dragonfly's life,

it's often lost parts of its wings,

and the colors have begun to fade.

It's a brief existence.

Seven or eight-week old
dragonflies are ancient.

If they haven't been eaten
by their natural enemies,

they'll eventually fall
exhausted to the ground.

Damselflies have an even shorter life,

not more than one or two weeks.

They fulfill a biological
function even after death,

they're food for other
animals, such as ants.

But the biggest enemy of
dragonflies, is autumn and winter.

As the temperatures drop,

dragonflies have no chance of survival.

They're cold-blooded and
depend on a warm environment

to keep their metabolism going.

With the first frosts,

the dragonfly season
rapidly reaches its end.

Further south, close to the Mediterranean,

they have a longer lease on life.

Often they live on small and
sometimes tiny rocky islands.

There may be no source of fresh water,

local vegetation has adapted
to the desert conditions.

Humans too, have colonized
these inhospitable islands

using technology.

But how do dragonflies
survive without fresh water?

The answer is simple and strange.

Individuals constantly
fly in from over the sea

because without a supply of fresh water,

it's impossible to reproduce.

When winter takes hold
in the temperate zones,

all the dragonflies have died.

The next generations spend
the winter as larvae

beneath the surface in
waters that never freeze.

But some insects manage to
survive the frost and ice,

Like the brimstone butterfly,
it can be frozen stiff

but will thaw into life again in spring.

This is made possible by
the glycol in its blood.

And the same is true of
the winter damselfly.

Of the thousands of dragonfly
and damselfly species,

only two can survive the winter.

When the spring sunshine
awakens the insects,

the ancient cycle of life begins again.

Dragonflies will soon take to the air,

as they have for 300 million years.

Unfathomable ages before
the time of the dinosaurs,

or human beings.