Spring The Great British Year

We are an island nation.

Surrounded by seas and buffeted by winds.

With weather and seasons

like nowhere else on Earth.

Unpredictable, always changing,

defining the nature

of our extraordinary land.

And giving us...

Every year, Britain's landscape

undergoes an extraordinary three-month transformation,

into an oasis of abundance.

Every creature in the land tries to make the most

of this brief window of opportunity.

What separates the winners and the losers is one simple thing...

..timing.

At stake is life itself.

The race is about to begin.

The starting gun is a crucial planetary trigger

which passes almost unnoticed.

The spring equinox.

For six months, the country has been under winter's cloak.

The lack of light and warmth has taken its toll.

But on March 21st, everything changes.

For one precise moment, days and nights around the world

are of equal length.

For the next three months, the nights will grow shorter,

while the days grow longer...

and longer.

The lengthening days bring a surge of life back to Britain.

As the temperature passes seven degrees, a miracle happens.

Long before leaves adorn the trees,

the forest floor comes to life.

The plants that flower first have stored food in their bulbs

through the winter and get a useful head start.

And now the blossom bursts on the trees.

Britain is coming into bloom.

Blackthorn and pears are some of the first to flower.

In a pear orchard in Somerset, the sweet smells and bright colours

attract a very special insect.

Many weeks before it's warm enough for honey bees to fly,

this solitary bee is already going about its business.

It may only be late March, but she has already laid eggs

and is busy collecting pollen.

She has a simple approach

to pollen collecting.

Rubbing it all over her body.

The more visits she has to make, the more flowers she helps pollinate.

Her early emergence is a gamble, in poor weather, she will struggle,

but when weather is fair, she has the orchard to herself.

While the returning sun is triggering life on land,

the moon is stirring life in the sea.

Its pull gives rise to the high spring tides.

Where late winter storms meet high water,

the results can be violent.

But beneath the waves, nutrients are stirred from the deep.

Soon, even the ocean will bloom.

When this happens, one little creature will be waiting.

Off Studland Bay, in Dorset, sea grass beds

form the ideal habitat for one of Britain's most extraordinary fish.

The spiny sea horse.

These shy and secretive animals have an enchanting life story.

In the early morning light,

males woo females with some fancy fin work.

The female releases her eggs

into the pouch of the male.

It is he who will get pregnant

and he who will have to raise and protect their young.

His most crucial role is deciding when to let them go.

By the next full moon, the nutrient-rich ocean

will have been warmed by the sun.

He must get his timing right if his babies

are to make the most of the coming bounty.

It is early April and, on land,

trees are still bare.

But within, a change is taking place

that will have huge consequences for the bird life of Britain.

The rise in temperature has spurred on the growth of leaf buds.

And the minute creatures that live on them.

Two months ago, a winter moth laid this tiny egg on an oak tree.

The caterpillar inside is now ready to emerge.

But it takes most of the night to eat its way out.

It crawls to the developing oak bud,

where it will shelter until the leaves unfold.

Across the country,

billions of caterpillars are doing the same thing.

The stage is set.

In a few weeks' time, there will be a bonanza of munching caterpillars

and any animal which depends on them will have to be ready in time.

CHURCH BELLS RING

In our cities, spring declares itself in song.

As the sun comes up over the dreaming spires,

Oxford resounds to one of our most beautiful natural choirs.

BIRDS TWEET

The dawn chorus may fill humans with joy,

but for the birds it's a serious business.

This is how they lay claim to their territory and find a mate.

All bird breeding is time-critical,

but particularly so for our native bluetit.

Late breeders stand little chance of success.

This young male must find a suitable nest site

with which to woo a mate.

In the meantime, resident birds have an extra problem to contend with.

Tourists!

Around ten million of them

arrive every year for the start of the breeding season.

With so many extra voices, every bird needs to

stake his claim as loudly as possible.

It's the start of the great April race.

As some of us run the longest race of our lives,

all around us, the birds of Britain are racing too,

busy building nests for their young.

It's an activity that takes place even on our remotest islands.

The Farne Isles, off the coast of Northumberland, may look

lifeless in winter, but in spring, they become one of the most

significant breeding colonies in Britain.

The birds are drawn by the absence of predators.

But nesting on this rocky island also brings problems.

There just isn't much nesting material out here to be found.

The thousands of breeding shags look out for rotting seaweed

and washed-up sticks, but it's every bird for themselves.

As the time for egg laying approaches,

competition soars...

..as does the local crime rate.

Leaving your nest unguarded for a moment is asking for trouble.

It can take a long time to build a nest,

but a very short time to destroy it.

For the occupier, it's a rather bewildering homecoming.

With this level of sabotage,

it's amazing that nests are ever finished.

But finally, the big moment arrives.

The first eggs are laid.

Breeding has officially begun.

After a frenzy of preparation, the trees

and forests of Britain go strangely quiet.

Britain's birds lay an estimated 800 million eggs each spring

and every one of them needs to be kept warm and dry.

Tricky in a country famous for its ever-changing weather.

High above the land,

scattered rain clouds form,

bringing sudden downpours -

our legendary April showers.

# Under this national rain cloud

# I'm getting soaked to the skin

# Trying to find my umbrella

# But I don't know where to begin

# And it's simply irrational weather

# I can't even hear myself think

# Constantly bailing out water

# But still feel like I'm gonna sink... #

THUNDER RUMBLES

Beneath the Forest of Dean, in Gloucestershire,

lies an ancient labyrinth of limestone caves.

Sheltering inside is the world's most northerly

population of greater horseshoe bats.

They have hibernated together throughout the cold winter,

dropping their heart rates and reducing their body temperature

to just above that of the surrounding air.

It's finally time to wake up.

The insects that they eat are taking to the air and so must they.

But first, they have to warm back up...

by shivering.

It's a risky business, as it requires a lot of energy -

the equivalent to six whole days of hibernation.

They now desperately need to find food.

But outside the cave, the rain has grounded the insects.

A special night-time camera shows the warm-bodied

bats as they take to the air.

They flit around the cave entrance but, without eating,

they're wasting valuable energy.

They have survived the coldest weather

that their species must endure anywhere,

and are now on the edge of survival.

Though tonight, they're in luck.

The rain eases off and the insects emerge into the moonlight.

Different species of bats, from miles around,

swoop in for a midnight feast.

The bats can eat up to 3,000 insects a night,

a third of their own body weight,

just what they need after their winter fast.

Thanks to new camera technology,

this magical spring spectacle can now be seen for the very first time.

The feast doesn't last for long.

As the evening cools, the insects disappear

and the bats return to roost.

Just missing the returning rain.

HEAVY RAIN FALLS

April showers make life difficult for birds too.

It's no fun sitting on eggs in the pouring rain.

Back on Farne, the shags are taking the egg-sitting in turn.

On the other side the island,

one of their neighbours isn't so lucky.

Female eider ducks are deserted by their mates,

and must do all their incubating alone.

This female is part-way through a marathon 30-day brooding session.

Unable to leave her eggs even to eat,

she will lose 40% of her total body weight.

Another group of neighbours faces a different

set of parenting problems.

50,000 guillemots live on these exposed cliffs.

They don't waste their time with nests.

Instead, they simply rest their eggs on their feet like penguins.

The eggs' conical shape reduces the risk of them rolling away

and smashing on the rocks below,

but every handover is still a precarious business.

Runaway eggs, however, are only one of their problems.

Herring gulls are everywhere...

Gulls aren't the only ones feasting on eggs.

It's Easter and the end of the Lent fast.

At this time of year,

chocolate eggs are seen as a celebration of new life.

# Thank you for the days

# Those endless days Those sacred days you gave me... #

Hunted or given as gifts,

every Easter, 80 million eggs are cast in chocolate.

# ..I won't forget a single day Believe me

# Days I'll remember all my life

# Da-a-a-a-ays

# Thank you for the days

# Those endless days Those sacred days you gave me

# I'm thinking of the days... #

Spring is now in full flow

and baby animals are appearing everywhere.

# Days... #

One of the most iconic signs of spring is one of its late arrivals.

At the 11th hour, bluebells appear,

transforming our green woodland floors into a carpet of violet.

Almost half the world's bluebells grow in our country -

making this a world-class British spectacle.

For the bluebells, this is their chance to reproduce.

Soon the tree canopy will close over

and their light will be shut off.

We have just a few short weeks to enjoy them.

By May, the Great British oak is unfurling its leaves -

one of the last trees to join the canopy.

Leaves are the trees' solar panels that will allow them

to grow all summer.

There are almost 1.5 billion deciduous trees in Britain.

Between them, they unfold over 50,000 square miles of foliage,

around half the area of the UK.

The arrival of the canopy cuts off the light to the forest floor.

The bluebells' brief moment in the spotlight is over.

As the new leaves unfold, it's time for the winter moth

caterpillars to have their moment in the sun.

Voracious feeders,

they may eat up to 27,000 times their own body weight.

But where there are hungry caterpillars,

there are also hungry birds.

The male bluetit finally found himself a mate,

and they have a healthy clutch of chicks.

At first, just the odd small caterpillar will do...

..but as the chicks grow, so do their appetites.

Before long,

the poor parents are supplying up to 500 feeds a day.

That's 40 an hour, or one every 80 seconds.

But just when the chicks are at their hungriest,

their food starts fighting back.

As the oak leaves develop, they begin to fill with poisons,

and so do the caterpillars that eat them.

It's a fiddly job but each caterpillar must now be

gutted before being fed to the hungry chicks.

Parents work all hours of daylight to feed their young.

Unfortunately, this couple were late to lay their eggs

and the caterpillar glut lasts less than a month.

Timing is everything.

By late May, the country is filling up with babies.

Life doesn't get any easier for the parents.

A mother stoat has gone off hunting...

..while the young play at being hunters themselves.

Catching dinner isn't an easy business,

even for an expert.

Finally, the young are rewarded.

Where one family loses, another one wins.

As life on land changes through spring, so does life at sea.

The nutrients released by the winter storms, combined with

the increased light and warmth, fuel an explosive growth of algae.

Eventually, they produce plankton blooms that are

so enormous they can be seen from space!

Indeed, half the oxygen we breathe is made,

not by plants or trees, but by these algae.

They are a foundation for life in our oceans.

But you don't have to be big to appreciate them.

The male sea horse has been carrying his young for four weeks

and is now heavily pregnant.

Until now, his brood pouch has supplied them with food and oxygen.

But all that is about to change.

As the May full moon appears, his contractions begin.

The fry are now on their own,

dispersed on the current.

By timing their birth with the plankton bloom,

their father has given them the best possible start in life.

The spring bloom is critical to all life that feeds from the ocean.

All around the country,

animals have timed their behaviour to make the most of these riches.

On the Farne Islands, chick-feeding is now in full flow.

And there are a lot of mouths to feed.

On these rocky outcrops,

more than a quarter of a million birds are now in residence,

including guillemots, kittiwakes, and more than 3,000 Arctic terns.

Despite the diversity,

all the birds on the island feed on one thing - sand eels.

In spring, these tiny fish feed in the sun-warmed, plankton-rich

surface waters, bringing them within easy reach of divers.

Each chick needs around five sand eels a day.

During the breeding season,

many millions of sand eels will be eaten in the Farne Islands alone.

For the few spring months, these remote

and rocky islands are transformed into a hive of activity -

all thanks to one little fish and its love of plankton.

For the female eiders, the long, lonely vigil is finally over.

Rather than bringing food to their chicks,

these mothers can bring their chicks to the food.

The chicks are less than a day old,

but already taking their first steps to independence.

The mothers are leading the chicks to a secluded pool

for their first swimming lesson.

The excitement is almost unbearable!

But the new arrivals haven't gone unnoticed...

On her way to the pool, one mother has been caught in the open.

She has two chicks to protect,

but neither realises the danger they're in.

There is nothing left but to get her remaining chick to safety.

At the pond, the mothers share the baby-sitting

and the ducklings are safe for now.

As May draws to an end, the sun gathers strength

and our days continue to lengthen.

Finally, an event high in the atmosphere

signals the start of our summer.

The sun's movement pulls the jet stream north,

leaving behind more settled weather.

This is what one animal has been waiting for.

At the River Bourne, on the Salisbury Plains,

it's a perfect afternoon for fly-fishing.

And a perfect afternoon for flying.

For the last two years, the larvae of the true mayfly have

been feeding in the shadows, but now their moment has come.

While some animals take months to reproduce,

mayfly need just one perfect day.

It has finally arrived.

It can take a while to get used to new wings,

and many never do.

Against the odds, some make it up into the air.

But danger is never far away.

As more and more emerge, the air becomes thick with mayflies -

more than any predator can eat.

Adult mayflies have only one function - to mate and lay eggs.

As the shadows lengthen, the males begin their first,

last and only dance.

For one afternoon only...

..love is on offer.

MUSIC: "Amoresque" by Sid Phillips Trio

They fly into the air and parachute down,

using their tails to break their fall.

As the evening draws in, the fertilized females

return to the water for the final act of their short adult lives.

FLIES BUZZ

While they still have energy, they lay their precious eggs.

Only a small fraction will ever make it to adulthood.

As for the females, there's nothing left to do.

Their one day in the sun is over.

At last, May turns to June -

the driest and sunniest month of the year.

Dandelions become feathery clocks...

..and cow parsley lines our country lanes.

In Britain, it sometimes feels like summer barely arrives at all.

But when the sun finally comes out,

it feels, for a few perfect days, as if it will last for ever.

# If I'm drinking, then I'm buying

# And I know there's no denying

# It's a beautiful day The sun is up, the music's playing

# And even if it started raining

# You won't hear this boy complaining

# Cos it's a beautiful day

# It's a beautiful day. #

The 21st of June is the longest day of the year.

On Farne, that means 17 hours of daylight.

The guillemot chicks are now three weeks old,

getting bigger and stronger by the day.

But with 20,000 new chicks, space is becoming even more of an issue,

and relations even more fraught.

BIRDS SQUAWK

All too often, it's the chicks that are caught in the middle.

There's only one way off the island.

But it's a long way down.

It's a calm day and the tide has been rising all afternoon.

Perfect conditions for takeoff.

The mums wrangle from above

while the dads call encouragement from below.

Some mothers turn to tough love.

It's a bumpy ride...

..but a soft landing.

Others aren't so lucky.

It really is a leap of faith.

As the longest day of the year draws to an end,

the families begin their trek to the fishing grounds.

The chicks won't touch land again for at least two years,

when they too become parents.

It's the beginning of an extraordinary journey -

not just for them, but for all of Britain's young animals.

The parents who have fed and protected them

will soon begin to move away.

And the young will have to learn the hardest

lesson of all -

how to survive on their own.

The key to filming British wildlife is perfect timing.

For any successful shoot,

the crew needs to get the camera into the right spot.

With the right conditions and, of course,

the animals need to play ball.

But when and what the animals

and plants are doing is closely tied into the weather.

And in Britain, as we know, that can be hard to predict.

The team always knew it would be challenging.

However, they could never have known just how big

a part our British weather was about to play.

This is now the fourth consecutive day of this awful weather.

It's raining quite a lot. Mixed with hail.

I can't feel my hands. It's horrific.

We just have to wait for the wind to drop. And it to stop raining.

As filming started, the team got their first surprise

with the warmest March on record.

To capture some of the key spring sequences,

the team had targeted the famous sea bird

hotspot of the Farne Islands, just off the coast of Northumberland.

But first, they had to get a crew to the island.

Cameraman Lindsay McCrae arrived with cameras and equipment,

but the unusual warm weather had brought in fog

and all the boats had been cancelled.

We can't go over because of this fog. It's a curse, isn't it?

Oh, right. I'm going out with some divers,

so if you want a lift across, I'll give you a lift across. Now?

In the next few minutes. A few minutes? Yeah, if you want a lift.

Brilliant, yeah.

A bit of local help goes a long way in wildlife film-making.

Now, with thick fog shrouding the island, there was

just the small matter of being able to get a clear shot of anything.

Lindsay had been hoping to capture the cliffs

before the birds arrived to nest, but the warm March

had brought everything forward - they were already here.

But these clouds had a silver lining - it gave him the

opportunity to capture the devious shags stealing each others nests.

Spring had started earlier than anyone could have predicted.

In the Wye Valley, in Gloucestershire, the team rushed

to deploy their specialist thermal camera to capture a key moment

in the lives of a colony of rare greater horseshoe bats.

Any sign on them? No.

Not knowing if they were too late, all they could do was wait.

It was that night in early April

that the first few drops of rain started to fall.

I'm glad you're protecting hundreds of thousands of pounds' worth

of camera equipment with a plastic sledge. A toboggan.

THEY LAUGH

The bats finally emerged,

but they didn't seem to think much of the weather either.

As soon as they had left the cave,

they very quickly flew back in again.

A normal British year was bad enough,

but this one was turning out to be exceptional.

Heavy rain causes more flooding

and disruption across large parts of Britain.

It's the wettest April for a century.

Nearly 200 flood alerts and warnings are in force. More rain is predicted.

THUNDER RUMBLES

And back on the Farne Islands,

it was having a serious effect on the birds.

Despite most arriving early, breeding was now behind.

On this visit, Lindsay was hoping to film the chicks,

but found only adults sitting tight on eggs.

It started off a lovely a morning but now it's just downright grim.

I've been trying to get any behaviour, really,

with all these birds -

the kittiwakes, the shags, the guillemots.

All the birds are on eggs.

You'd think they'd have to swap at some point.

With not much to film and terrible conditions to film them in,

Lindsay decided to head back, but even this was problematic.

This is now the fourth consecutive day of this weather.

I lost a day at the start of the trip because the weather was so bad.

The weather's been awful while I've been here.

So we've really struggled to get what we were after.

All I've got to do now is wait

and just jump on that next boat to get back to the mainland.

It's mad.

Now, with strong winds and big waves, boats were cancelled

and Lindsay was stuck again - this time, unable to get off the island.

And the awful rain was showing no sign of letting up.

NEWSREADER: 'It's the second wettest June in the UK since records began.

'And we haven't got to the end of the month yet.'

If there was one sequence that needed dry weather,

it was the mayfly.

To stand any chance of filming this, the crew needed help.

Assistant Producer Jo Avery was fast becoming best friends

with the Met Office.

Just calling up for a weather update.

I was wondering if there was any sunshine or settled weather

forecast in the next week or so.

SHE SIGHS Oh, great. OK.

The forecast wasn't good, but the team had to give it a go.

They headed to the River Bourne, in Salisbury,

where mayflies had started hatching,

but in this weather, capturing it on film was just about impossible.

We just have to wait for the rain to stop, the wind to drop,

the light level to rise.

It's not a good day for filming mayfly.

With spring 2012 now officially the wettest on record,

the risk of completely losing this major sequence

was becoming very real.

But as the crew waited, their luck changed.

At last, there was a break in the weather,

and the team were in business.

Of course, it wasn't just the crew waiting for this key spring moment.

For many animals, this event was providing much-needed food.

It was a timely reminder to the team that challenging weather

can be life-changing for British wildlife.

On the summer solstice, the crew returned to the Farne Islands

for their final filming trip

to try to capture the guillemot chicks jumping from the cliffs.

For once, the weather was smiling on the team,

but how would the wettest spring in decades have affected the birds?

The terns seemed to have done OK.

This time, it wasn't rain falling on the crew!

So the tern chicks had survived, but what about the guillemot chicks?

Good news. They were all safe on the cliffs.

And Lindsay was in place to film as the chicks started to jump.

For us, it had been a fraught spring,

but for our wildlife, it had been a battle to survive.

To get a free copy of this poster about British seasons,

call 0845 271 0017.

Or go to bbc.co.uk/greatbritishyear.

Follow the links to the Open University

and take part in our seasonal wildlife census.

Subtitles by Red Bee Media Ltd