Original subtitles

(slow music)

(upbeat music)

No doubt about it, no other insects

make us as happy as bumblebees

wherever we happen to see them.

On snowy meadows or in our town centers.

And wherever a bumblebee flies, there'll be flowers.

They use all the daylight there is.

They work about 18 hours a day all the way through

the summer, much longer than their honey bee cousins.

But who knows about their dark side, about the secret places

and their dark nests hidden underground?

Bumblebees fly up to 6,000 meters up mountains.

Some of them will only live in high alpine regions.

Some are still a complete mystery.

Their nests have never been filmed.

Bumblebees have enemies as well.

Some colorful, others furry.

(bee buzzing)

(mid-tempo music)

They don't get a friendly welcome everywhere.

But if they have to defend themselves they will,

and they'll use their powerful sting.

Challenge a bumblebee, you run a serious risk of losing.

This film follows a young bumblebee queen through a year

to experience with her the life of the bee's furry sisters.

(slow music)

Our story starts late in winter,

or rather at the very beginning of spring

when you feel the days growing longer

and the sun regains its strength.

Next to the last spots of snow, the year's first blossom

on this (mumbles) cherry tree.

With the temperature only just above freezing,

the first buds are opening.

And the first warm rays of the sun bring out the flies.

It's still too early for most insects,

the few that didn't die with the cold last autumn.

But where is the next generation

waiting to fly, drone, and buzz its way into the world?

About 20 centimeters down beneath the snow and earth,

the bumblebee queens have survived.

Their colonies died in the fall.

Here they lie frozen until they're awakened by the sun.

The glycol in their blood stops them freezing to death.

But if the snow thaws slightly bringing moisture

and ice crystals, they can't stand it too long.

This bumblebee urgently needs some real warmth

to end her hibernation safely.

(bumblebee buzzing)

Dizzy and still tired, our queen

tries to reach light and warmth.

It's six months since she started her long winter sleep,

but she's finally woken up.

Her first task, cleaning her characteristic

yellow, black fur.

Bumblebees appear to be relaxed and friendly insects.

However, scientists are regularly surprised

by bumblebees and their behavior.

We're a long way from uncovering all their mysteries.

(gentle upbeat music)

A bumblebee can start to fly at two degrees above zero.

It's no problem for them to cross big fields of snow,

but they're always on the lookout for blossoms and food.

Our queen is hungry.

She needs energy fast.

But she's out of luck.

(dramatic music)

(water flowing)

This bumblebee was already weak,

but now she has a much worse problem.

If she doesn't reach the bank quickly, she'll soon be dead.

(slow music)

Our bumblebee lives in the foothills of the Alps.

The climate is harsh here,

not the best premise for survival.

Only a few bumblebees will survive their first days.

Just a few hundred meters lower the temperatures are milder.

Here the spring's explosion is reaching its climax,

and the insects will find enough food

to regain their energy.

(gentle upbeat music)

Butterflies that survived the winter, like this Comma,

find their nectar in the dwarf laurel's blossom.

All around are willows with their yellow catkins.

There are about 100 different kinds of willow trees.

They burn bright like torches

at the edge of the still pale woods.

These catkins are one of the most important food sources

for insects in the springtime.

This is a hornfaced bee, distantly related to the bumble.

The pollen seems to have blocked her proboscis.

It's collapsible.

It helps to gather nectar and other liquids.

(slow music)

Proboscises come in different lengths depending on

the species of bumblebee and their specialization.

For the early flying insects, the blossom

of the goat willow is a vital first food.

The first honey bees of the year dip greedily

into the nectar of the willow catkins.

(bees buzzing)

Back up the mountain to our bumblebee queen.

Spring has not yet arrived here.

The grass frogs may be in the mood for love,

but not every animal can take the cold and damp,

especially not the insects.

(slow music)

Our queen has survived her accident

and the dive into the icy water.

She was helped by her fur,

which insulates her against the cold.

Now she really has to get a glimpse of sun

and energy-rich food.

In the blossom of the Easter Rose,

she finds the energy source, nectar,

which she greedily sucks out with her proboscis.

Restored to full strength, she aims for her next goal.

Here in the fields of spring she has to find a new home,

a home for the coming season.

Ideally a burrow abandoned by another animal.

(upbeat music)

Our bumblebee queen starts a long recce flight.

She needs to find a hollow in the ground

to build into a nest.

Bumblebees breed in a nest.

If they find holes left by mice, birds, or weasels,

they'll occupy them.

Burrows like these are perfect for them.

Ground squirrels build burrows and live in them.

They definitely don't like bumblebees.

They know bumblebees have only one aim,

to intrude into their nests.

The rodents had these rudeness

and they know how to counter it.

They clog the burrow with themselves.

(water babbling)

(slow music)

The greater mouse weasel, or ermine,

likes to build little burrows in the earth.

But only for its own use, and to impress its spouse.

Faster than you could imagine,

our bumblebee queen appears and senses an opportunity.

But the ermine is watching.

Back to the drawing board.

Another place that might mean shelter

are birds nesting boxes.

But sometimes they're occupied.

As in the case of this black redtail family.

No room here, especially not for a lodger.

This pair of blue tits moved

into their comfortable home some weeks ago.

It's dry and tucked away,

perfect for the parents and their six youngsters.

(birds chirping)

The entrance is very small, three centimeters at most.

Perfect, no larger animal can slip through.

The blue tit's enemies are locked out.

(birds chirping)

Our bumblebee queen happens by.

Of course, she's attracted to the nesting box,

especially to the tiny hole which is the entrance.

(bumblebee buzzing)

The blue tit knows something bad is coming.

The bumblebee seems hypnotized

by the tiny hole, and what's behind it.

(slow music)

The blue tit must get back inside the nesting box

before the bumblebee to keep her offspring safe.

The blue tit's powerful instinct to save her brood

makes her ignore the danger of being stung or bitten.

Bumblebees are tough adversaries.

They cling on tight.

(dramatic music)

(slow music)

The young bumblebee queen has lost out again.

But luckily she's not hurt.

If she'd lost one of her wings, that would be the end.

Bumblebees are tough and can stand hard fights.

But our queen needs to find a home really urgently now.

Without a base, she won't be able to breed,

and she has to to survive.

This could be her last chance, a mouse hole.

She buzzes around it for several minutes, another recce.

Will she dare explore further?

Okay, the decision is made.

She goes in, into the lion's den.

She seems nervous.

This can be seen by the fact

that she's repeatedly cleaning herself.

Mouse holes go down about 20 or 30 centimeters.

Only at the end will she know if this one is inhabited.

(dramatic music)

Again, our queen seems to be out of luck.

The mouse has fully furnished this home.

She seems to have lost her courage at the last moment.

And now the mouse has spotted the intruder.

Our bumblebee has made up her mind to fight.

She's determined not to give up this time.

Raising her leg is a clear sign.

If you approach me, I will fight.

The mouse retreats.

She respects the bumblebee's sting and her powerful jaws.

Now the bumblebee takes her chance

and enters the mouse's living room.

But this isn't the end of the battle, no way.

Mice are tough fighters, and to expel them

from their own nest is a challenging task.

This could be a life or death struggle for both parties.

Suddenly, victory for the bumblebee.

The mouse surrenders.

The bumblebee's aggression has won the day.

The mouse abandons her own home.

After this strength-sapping battle she needs a rest.

But what finally counts is that she managed

to expel a rodent 100 times heavier than she is.

Now she's the owner of a nest, and this will give her

the possibility of founding her own colony.

Nearby, a colony of tree bumblebees

have occupied an old nesting box.

They're one step further in their development,

because here we find a lot of working individuals.

They've hatched over the last few days.

The queen is the biggest bee inside,

and she's enthroned in the middle.

The numbers in the nest will grow into the summer

until there are about 100 bumblebees.

Compared to honey bees, this is a very small colony.

A beehive houses up to 80,000 bees.

Right now our queen has to hurry to produce some offspring.

She has prepared this honey pot.

It's made of wax and filled with nectar.

It's her food store, and she can drink from it

whenever the weather outside is too bad to fly.

(slow music)

Bumblebees do not make honeycombs.

They build their nests in a different way.

They produce wax and excrete it from their hindquarters,

and then they transfer it to their mandibles.

Then they form tiny cups.

The next step is to produce offspring.

She places her eggs in the little prepared cups.

They were fertilized the previous autumn

before the bumblebee retired for the long winter break.

She puts five to 15 eggs in each container.

In every egg there's a larva.

Within 20 days the larva will pupate.

The bumblebee queen is a surprisingly caring mother.

Every egg is treated very carefully.

She checks the eggs to make sure they're not damaged.

After that she seals the small bowls.

Now they can start to grow.

Outside the spring has reached its climax.

Countless buds are now open, and lure all kinds

of insects with their yellow pollen.

(slow music)

But what looks to us like a snowy white dreamland

looks very different to bumblebees.

Science tells us a bumblebee's world

is tinted blue, like this.

It's April, and the lure of the fruit blossom

has become irresistible.

Apricot and apple blossom are a special feast.

These are idyllic times for bumblebees.

And the fruit orchards of the alpine uplands

offer a supply of pure energy.

The latest studies suggest that bumblebees might have

the fastest color recognition of all animals.

It takes them milliseconds.

This honey bee is enjoying her bath in dandelion pollen.

Honey bees are proverbial hard workers.

But bumblebees visit five times more blossoms everyday.

And bumblebees have a unique way

of taking care of their brood.

Again and again the queen huddles up to her spawn.

She brings them up to a temperature of 35 degrees Celsius.

No other insect shows such care while breeding.

20 days later, the big moment.

The bumblebee offspring hatch.

At the beginning of its life

a bumblebee is colorless and soft.

Even her wings haven't unfolded.

Safe in the nest, they dry out quickly.

Inside the nest the temperature is about 30 degrees Celsius.

One after the other the bumblebees hatch.

They're all workers.

The queen's colony is steadily growing.

During the summer, the colony may reach 500.

Now, the queen produces eggs and nothing else.

She will not leave the nest again.

Spring shifts into summer.

Common lungwort is visited by a number of different insects.

For example, the carder bee.

But not everything here is what it seems.

(upbeat music)

The large bee fly looks like a bumblebee

at first sight, but it's not.

This is a fly and has an extremely long proboscis.

This animal carefully cleans its proboscis and wings.

Grooming is very important for flying insects.

Any infestation of parasites would lead to a quick death.

Bee flies have dense hair-like fur.

They specialize in bumble blossoms just like the bumblebees.

Through mimicry they have a massive advantage

because they have very few predators.

Anything that looks like a bumblebee

won't be attacked while out looking for food and nectar.

But there's more to come, bumblebee flies.

This kind of fly even imitates the bumblebee's colors.

Seen from a distance, it's almost impossible to tell

if it's a bumblebee or a fly.

But even the best camouflage can be useless.

Nobody can cheat this specialist, the bee-eater.

These colorful birds love to live in regions

with a mild Mediterranean climate.

They breed in clay and (mumbles) walls.

And they like eating flying insects.

The bee-eaters' name is their game.

Bees are their preferred food.

They catch bumblebees on the wing with their powerful beaks.

They're extremely skilled at squeezing the insects

to remove their stings.

Prepared, chewed, and softened,

even bumblebees provide an excellent meal.

(slow music)

A flower garden is not an ideal habitat for bee-eaters,

but it's a perfect place for bumblebees.

This garden means blossom in abundance, full of nectar.

And there are some gardeners who are never satisfied

with the number of bumblebees they find on their land.

For thousands of years, bee keepers

have kept bees in hives to make honey.

But only in the 21st century have we seen

the flight of the bumblebee coming from a box.

Westerlo is a smalll town in Belgium.

White-tailed bumblebees are bred here.

(mid-tempo music)

Gardeners like to have bumblebees in their backyards

because the busy insects set off straight away for blossoms.

The tiny animals are examined in this laboratory

for parasites or diseases before they're allowed to breed.

This takes place in controlled conditions.

Every queen has her own colony,

and every colony has its own container.

Hundreds, thousands, hundreds of thousands.

As soon as the first workers have hatched

they're fed pellets of pollen,

an artificial environment that provides

as much energy for development

as the best natural surroundings.

This is the industrial breeding of bumblebees.

They're bought by large gardening companies

who are guaranteed regular harvests

by the pollinating bumblebee colonies.

Fruit growers increasingly deploy bumblebee colonies

when a cold or damp spring

has disrupted the flight of the honey bees.

Seeing bumblebees in plastic nests as domesticated animals

is still a strange idea for many.

The first young bumblebees hatch.

Now the breeding box is getting too small.

The bees have to change their container.

This one is bigger, and the red light calms the bees.

Finally the bumblebees are provided with a supply

of liquid nourishment for the long journey ahead.

Every year about 400,000 young bumblebee colonies

invade Europe from this plant in Belgium.

And these portable colonies fertilize

millions of crop plants across the continent.

(slow music)

If honey bees work hard, bumblebees work even harder.

They collect pollen up to 18 hours a day.

That's 1,000 blossoms day in, day out.

In greenhouses too, gardeners prefer

to have bumblebees pollinating their plants.

Today we harvest tomatoes in greenhouses

from March to October thanks to all the bumblebees.

Summer has come.

Our queen's colony has made good progress.

All the workers return with their

pollen sacs full to the brim.

It's a very good sign.

The pollen will be stripped off

into little storage containers made of wax.

(slow music)

The deposited pollen and nectar

will be food for the whole colony.

In the middle of the pulsating nests, it's the queen.

Her duty is to produce eggs.

More and more and more of them.

(soaring orchestral music)

High mountains are a barrier to many animals.

But not for bumblebees.

In India, bumblebees have been sighted at 6,000 meters.

And in the European Alps they're often seen on glaciers.

Some species are extremely resistant thanks to their fur.

Take the buff-tailed bumblebee.

This species creates colonies at an altitude

of up to 2,700 meters.

Bumblebees are located all over the Northern Hemisphere.

But they prefer landscapes with temperate cooler weather.

High mountain meadows, even far beyond the treeline,

contain many insects attracted by

the great variety of wild flowers.

(water flowing)

The alpine climate is cold and moist.

Some species of bumblebees cope well

with these conditions and stay forever.

(slow music)

This grass bumblebee is one example.

Many bumblebees have become habitat specialists.

For example, the mountain forest bumblebee.

This species likes to be in very high

and exposed alpine regions.

The gray and white dumbledore

is a purely alpine bumblebee species.

Besides its coloring, its special feature

is its conspicuously rough coat.

But the dumbledore is still a mystery today.

Her colony rarely exceeds 50 individuals.

These are the first pictures ever taken

inside a dumbledore nest.

Living here up in the cold mountains

is the results of a long, long evolutionary adaptation.

Fur protects another inhabitant

of mountain regions, brown bears.

(bright music)

Though his diet is mostly vegetarian,

he also likes to look for insects.

And even the biggest and strongest bear

has one little indulgence, his greed for honey.

It's in many books and fairy tales, and it's true.

Hollow trees are most likely to house wild bees.

Bears' noses are very sensitive.

They can smell honey from hundreds of meters.

(slow music)

And it's not always honey bees

that produce this enticing smell.

Bumblebee's nests too exude a tempting scent of honey.

(dramatic music)

Once the bear has made up his mind, he's unstoppable.

Even stings to his head won't deter him.

On the contrary, they seem to spur him on.

The big claws on his powerful paws

are an excellent tool to tear apart underground nests.

The bumblebees face total destruction.

Now the bumblebees have to abandon their nest.

The bear grabs big chunks and swallows them whole.

Along with the sweet nectar he devours

larvae, pupae, and bumblebees.

And this seems to make his feast even more delicious.

(slow music)

He waddles away satisfied and unfazed by the bees.

Has he already caught the scent of the next honey supply?

(bright music)

But several bumblebees have been caught in his coat.

They can take sweet revenge

for the destructive interruption.

(slow music)

Some bumblebee species are true specialists.

They take an adaptation to a new level.

This is the monkshood bumblebee.

It lives only in the Alps

between 800 and 2,500 meters above sea level

and it has the longest proboscis

of all the Europe subspecies.

It uses it to suck up water from small puddles.

Fights easily break out over the best sites.

But this impressive drinking tool actually developed

for a completely different reason.

One that has to do with a flower,

the Aconitum, or monkshood.

(slow music)

There are several species of this poisonous plant

in the alpine region.

It's not hard to see why the plant is called monkshood.

Take a closer look.

The petals look like tiny hoods.

The monkshood bumblebee specializes in gathering nectar

from these bizarrely shaped flowers.

It has to climb over the flower's stamens

to get to the nectar, which is at

the opposite end of the flower.

And even then the bumblebee can only reach it

thanks to its long proboscis.

The monkshood bumblebee drinks

almost exclusively from these flowers, and vice versa.

The monkshood depends on this

bumblebee species for pollination.

No other insect will climb through its blossom.

It's a textbook case of co-evolution,

where two species develop

uniquely well matched characteristics.

Perfect synchronization, but it's also risky.

Because is one disappears, the other is doomed.

Not all these co-dependencies have been discovered.

But it's a fact that among the bumblebee varieties

there are endangered species.

And it's a fair assumption that their extinction

may well mean death for a number

of so far unidentified flowers.

(slow music)

When summer starts most meadows are still

a sea of flowers and a riot of colors.

These colors have only one purpose,

to attract pollinating insects,

bees, bumblebees, butterflies.

But as summer reaches its peak,

the luxuriant splendor begins to wane.

Ears of cereal now dominate the landscape.

Red poppy and blue cornflower have long since faded.

Field borders are true sanctuaries during these meager times

when food supplies dwindle so drastically.

(dramatic music)

Midsummer also brings the mowers and the scythes.

When the meadows are cut there are even less flowers

for the nectar hungry insects.

But meadows have to be cut back,

otherwise grass has gained the upper hand.

Meadows are man-made landscapes,

a cultivated coexistence of grasses and herbs.

Many farmers who practice near natural farming

have begun to mow their meadows in several stages.

This means significantly more work

and it can't always be managed.

But the insects that pollinate the flowers

then have more time and opportunity to gather reserves.

(slow music)

Meadows can be very varied.

They're home to hundreds of different plants

and precious habitats for a variety of living creatures,

some of them only visible under a microscope.

When vast meadows are cut down in summer,

the pressure of competition among

pollinating insects increases dramatically.

The more variety there is in the remaining green space

and the denser the vegetation, the greater the number

and variety of insects that can survive.

Flower gardens are a perfect biosphere.

They provide a steady supply of flowers until late summer,

vital for nectar gathering insects.

(slow music)

Even urban communities are starting

to develop more biospheres.

In Austria's green cities, more than 70% of the surface area

provides places for bumblebees to find

new food supplies in the summer months.

Even inner city parks and ornamental borders

serve as vital filling stations for nectar.

In August, dead bumblebees

are beginning to line the streets.

Sensitive landscape gardening may provide food supplies

throughout the summer months.

But now the cycle is reaching its end.

(slow music)

One of the last lifelines is the late blooming silver lime.

Their tiny yellowish flowers bloom until late August.

Silver lime trees are irresistible to hungry bumblebees.

The flowers of the silver lime contain mannose,

a kind of sugar long suspected to be lethal for bumblebees.

But the theory is wrong.

At least, it's too simple.

Nature is more complex than that.

Mannose or no mannose, bumblebees

love the silver lime's nectar.

But the long meager months of summer

have weakened the insects and the competition is fierce.

The energy needed to reach the precious nectar

exceeds the energy the bumblebees

can extract from the flower.

(dramatic music)

So they die.

To survive a bumblebee needs

about 150 milligrams of sugar a day.

It's the shortage of nectar at the very end of summer

that kills so many bumblebees

and makes them food for the ant population.

However, there is another great danger.

The most dangerous parasite for bumblebees is the bee moth.

It eats the wax, spins, and pupates in the bumblebee nest

and leaves as a fully grown moth.

Once the bumblebee nest has been breached,

pests like moths and mites have an easy time of it.

Bumblebee mites are useful for the bumblebees.

They clean the nest of dung and waste products.

But an infestation of mites spells doom

for a bumblebee colony.

When mites breed en masse they damage the brood.

Many bees are left crippled and incapable of flight.

It's an ugly sight when the mites fix themselves

to the neck of the bumblebee and start to suck.

Bumblebees can't get rid of these parasites.

Back to our queen and her colony.

At the turn of the season something has changed.

The queen seems listless.

The colony is in turmoil.

The last year's queen tries quietly to retreat.

But suddenly mutiny breaks out in the ranks.

Her own brood starts attacking her.

The queen is stung, bitten, and flayed.

Until she dies.

The queen bumblebee survived the icy winter months,

claimed a nest, and founded a colony.

Now she's killed by her own offspring.

(slow music)

After six months of toil she has

served her purpose and is disposed of.

A merciless cycle of generations rules a bumblebee colony.

Shortly afterwards many large bumblebees appear

among the workers of the colony.

They are the new queens, hatched towards the end of summer

to ensure the next generation.

Now is the time to watch future bumblebee queens

leave their underground nests on their maiden mating flight.

Drones, the much smaller males of the species,

wait for a once in a lifetime opportunity.

They follow the young females hoping for a chance to mate.

Mating can last for half an hour or more.

And one insemination is enough to enable the queen

to start a new colony, next spring after hibernation.

(dramatic music)

Not all of them will get that far though.

Where bumblebees swarm, predators are never far behind.

And the courtship is so intense that the bumblebees

don't notice the approach of the praying mantis.

Future queen or hopeful beau, whoever is caught

in the mantis' spiked forelegs is lost.

The mantis will consume her prey completely.

Autumn has finally arrived.

Autumn crocuses, faintly reminiscent

of spring's earliest blooms,

are a last salute from the flower kingdom.

But the days of the bumblebees who now visit

the autumn crocus are numbered.

(slow music)

The promise of pollen still lures the bumblebees

to the last gentians, but their life has reached its end.

Once the leaves turn, frost is just around the corner.

When the leaves fall, so do the last of the bumblebees.

The colors of autumn are deceptive.

They no longer signal a source of food.

These leaves announce the arrival of winter.

Now all the colonies die.

Only inseminated future queens are required to survive.

They will find a hiding place underground

under moss and dead leaves

where they will go into (mumbles) for several months

protected by their furry exoskeleton.

When spring returns the young queens will emerge again

to found new colonies and play their role

in the endless cycle of nature.