LOW PEEPING
SHARP CHIRPING
LILTING SONG
LOW, BABBLING CALL
HIGH, REPEATING CALL
CHATTERING SONG
DAWN CHORUS BUILDS
SHRILL, WHIRLING CALL
On a clear spring morning like this, the dawn chorus is at its peak.
DAWN CHORUS CONTINUES
There are surely few more enchanting natural soundscapes than this.
DAWN CHORUS CONTINUES
But this avian choir does not sing for us.
These are songs of seduction and weapons of war.
Males are defending territories and attracting mates.
LOW CHIRPING
COOING
Singing is dangerous.
CUCKOO!
HIGH, CHATTERING SONG
It reveals the bird's location to predators.
But it also offers a huge reward -
the chance to attract a female and
pass on genes to the next generation.
That, Charles Darwin said, is why song evolved.
It was an example of what he called sexual selection.
But, today, new discoveries are transforming those long-held ideas.
For this programme,
I've chosen some of my favourite recordings from the natural world
that have revolutionised our understanding of song.
There are seven recordings of it
that have particular interest for me.
Some are lovely,
some are surprising,
and one almost broke my heart.
But all of them broke new ground.
ANIMALS SING
BIRDSONG, INSECTS BUZZING
I've recorded many sounds of the natural world over the years...
..and I've learned that there is, perhaps surprisingly,
no scientific definition of song.
We tend to use the word
to describe sounds that seem, to our ears, beautiful.
TUNEFUL WHISTLING
It is, in truth, a somewhat whimsical label,
but it has been attached to some of nature's greatest marvels.
Just listen to this.
WHALE SONG
Each of my seven chosen songs was recorded in my lifetime.
BOUNCING CHIRP
The oldest was made when I was five.
The most recent, just a few years ago.
CHATTERING SONG
None is closer to my heart than the first one...
HONKING CALLS
..which I made back in 1960.
HE CHUCKLES
WHOOPING CALLS
Recording audio in the field in remote parts of the world
was almost unheard of.
There was certainly no money in the BBC budget for a sound recordist,
but I did manage to get hold of a very rare thing indeed -
a battery-driven portable tape recorder -
so that I could record sounds myself.
It was a cumbersome piece of kit, but cutting-edge at the time,
and I was determined to use it to record a singer
that no-one had ever recorded before.
Madagascar's largest lemur, the indri.
EERIE WHOOPING CALLS
PAST ATTENBOROUGH: This noise was no bird call.
I had never heard anything like it before.
It must be the voice of the indris.
CALLS CONTINUE
PRESENT ATTENBOROUGH: Using my new equipment,
I made the first-ever audio recording of the indri.
CALLS CONTINUE
But could we also capture them on camera as well?
PAST: The song was so loud that it seemed impossible
that the animals could be more than 20 or 30 yards away,
but where were they?
CALLS CONTINUE
PRESENT: Until now, no-one had even managed
to photograph a living one, let alone film it.
PAST: Infuriatingly, the bush was so thick
that I could see no sign of them, whatever.
CALLS CONTINUE
So the question was, how could we get close enough
to get a clear view of them without frightening them?
"Well," I thought, "what about doing it the other way around
"and trying to persuade them to get closer to us
"by playing their calls?"
RECORDING OF INDRI CALLS PLAYS
And they did exactly what I hoped they would do.
RECORDING CONTINUES
NEARBY CALLS
They called in return, came down close to us,
stared at us, still calling.
INDRIS CALL
PRESENT: I was thrilled -
we had recorded their song and filmed them singing.
But why had this trick worked?
INDRI CALL
Well, because they thought that the song I was playing
meant a competitor was close by,
and their response was to sing.
And this suggested one thing.
There are such things as battle songs.
INDRI HOOTS
Songs that say, "Get out, this is my territory!"
INDRIS CALL
GENTLE BIRDSONG
It seemed to be a clear example
of Darwin's theory of sexual selection.
A male singing to defend his breeding patch.
But this was still just guesswork.
We suspected that songs could be weapons of war,
but it was the next recording that proved it.
LILTING CHIRPS
This is the song of a male great tit.
A call, a very simple song.
It was recorded by a scientist
who's been a pioneer in understanding animal song.
Professor John Krebs.
He was the one who proved for the first time
exactly why my playback trick in Madagascar had worked.
Spring 1975.
Back then, John was a young lecturer at the University of Oxford,
researching the birds in woodland just outside the city.
First, he plotted the territories of all the pairs of great tits.
Next, he recorded the songs of the males.
REPEATING HIGH-LOW CHIRPS
Female great tits do not sing.
Then, on a particular morning in February,
I came out with mist nets to catch the birds,
and I caught all the pairs of birds that were in the woods.
Now there were no great tits,
just empty great tit territories.
BIRDSONG
In some, John replaced the great tits with loudspeakers
that played the sounds of the birds that he had temporarily removed.
RECORDING OF GREAT TIT SONG PLAYS
If the song was a "keep out" signal,
then new great tits would avoid these patches.
RECORDING CONTINUES
Other territories were left silent.
No speakers, no great tit song.
New great tits should realise these spaces were empty and available,
and settle there quickly.
RECORDING CONTINUES
But how would John know that it was due to a great tit song
that newcomers had been deterred?
Perhaps any sound would have had the same effect.
So, in some territories, he played a recording of a tin whistle.
RECORDING OF TUNELESS TIN WHISTLE PLAYS
He could have chosen anything,
as long as it sounded nothing like a great tit.
And then I watched to see what happened,
and new birds came into the wood,
because this is a prime breeding area,
so birds love to come here to breed.
IT CHIRPS
John discovered that the first territories that were taken
were the silent territories,
and the ones with the tin whistle.
TIN WHISTLE RECORDING CONTINUES
Crucially, the territories in which the great tit song was played
remained empty of new great tits.
By looking at the detail of that pattern of settling,
I was able to show experimentally
that song is an effective "keep out" signal.
THEY SING
Professor Krebs' predictions were exactly right.
Song was a "keep out" signal to other great tits.
For the very first time, there was scientific evidence
that song was being used to intimidate rivals,
just as I had seen with the indris in Madagascar in the '60s.
How astonishing that it was only in 1975
that this was proved for the first time.
The song of the great tit had made history.
LILTING CHIRPS
BIRDSONG
Open a window in spring,
and these are the singers that serenade us.
CUCKOO! CUCKOO!
Songbirds.
They make up about half
of the 10,000 species of birds in the world.
Five of my sevens songs are sung by them.
Birds have the most advanced vocal organs in the entire natural world.
DEEPENING CHIRPS
We have our voice box at the top of our windpipe,
but their equivalent is at the base of theirs -
it's an organ called a syrinx.
They're the only creatures on Earth to have one of these,
and the syrinx of the songbird
is the most complex of them all.
BIRD SINGS
As breath passes through it,
muscles contract and vibrate,
creating the sounds we call song.
It can produce different notes
from the left and right sides simultaneously.
COMPLEX BIRDSONG
It's like having two voice boxes that can operate at the same time.
CHATTERING SONG
So this is how songbirds can perform
such unparalleled feats of vocal gymnastics.
But working out WHY they do is far more complex.
REPEATING RASPING CHIRPS
REPEATING BUZZING CALL
Each note lasts just a tiny moment and then disappears.
HIGH, BUBBLING CALL
That presents anyone who wants to study it with a problem.
HIGH, RAPID SONG
But there are two relatively recent inventions
that have helped us to capture songs.
CHATTERING CALL
It was with a gun mic like this, inside its windshield,
that John Krebs caught the fleeting sound of the great tit.
But it was the ability to take that recorded sound
and then turn it into a visual picture
that enabled us to analyse that sound
and reveal its full complexity.
LILTING GREAT TIT SONG
This is an animation of the male great tit song,
generated by a machine called a spectrograph.
It changes the song into an image that's possible to read.
DEEP CHIRPS
Slowed down, we can see that the great tit song is relatively simple.
CHIRPS CONTINUE
It's composed of two notes - one high and one low - repeated.
REPEATED HIGH CHIRPS
What we hear is very similar
to what we can see on the spectrograph.
CHIRPS CONTINUES
But compare that to the song of the male wren.
HIGH, RAPID, COMPLEX SONG
What we hear is not what the bird hears.
Birds live on a different timescale,
at a different pace from us.
And they can hear details in their song
that are impossible for us to hear.
It's only when we use a spectrogram that these details are revealed
A trill...
..a connecting note...
..another trill...
..and then a rapid burst of trills at the end.
RAPID TRILLS
Now we can see that there are perhaps 100 notes
or more in a song that may last only a few seconds.
RAPID TRILLS
SLOWED, UNDULATING BIRDSONG
RAPID TRILLS
What the spectrograms show are these songs are far more complicated
and complex than we could possibly have imagined.
But why complicate things so?
The calls of the indri and the great tit
worked perfectly well.
The answer, of course, is sex.
That is the reason why so many birds have such complex mating songs.
CHIRPS AND CHIRRUPS
Females seem to prefer them.
The more intricate and detailed the song is,
the better the male's chances.
And my third song helps to explain why.
RHYTHMIC BIRDSONG
It's a recording of a nightingale that is my next chosen song.
NIGHTINGALE SINGS
This is a male singing for a mate.
Just as with the great tit, the females do not sing.
But they are the ones the males are singing for.
So why do they prefer more complex songs?
It's a question that has puzzled scientists for centuries.
Charles Darwin's answer was that the females
have an aesthetic sense.
After all, human beings appreciate beauty.
Why shouldn't other animals do so too?
But the question Darwin didn't answer was
WHY should the females have an aesthetic sense?
Here on the streets of Berlin, we might just find the answer.
Spring attracts over 2,000 nightingales to this city each year.
They flock to Berlin because it's filled with green space,
much of which has been left untamed.
And it's these wild places that they love.
In one of its most popular parks, a male nightingale.
He, like the other males, arrived from Africa a few weeks ago
and has spent his time singing to defend a breeding patch.
But tonight, when the lights go out, he will change his tune
because the females have arrived.
RAPID CHIRPS
Nightingales migrate at night, and when the females fly in,
under cover of dark, they are met with songs of seduction.
COMPLEX TWEETS, TRILLS AND CHIRPS
Dr Conny Landgraf made our recording of the nightingale's song.
So right now, there's one... Oh, no there is a second male.
So it's already two males in a vocal contest.
What the females do is that they do not take the first male that comes
their way, but they prospect and inspect different male territories.
And this is like a speed dating that is actually
going on in the middle of the night.
OVERLAPPING BIRDSONGS
Each male sings his heart out and the females listen.
DING
Time's up!
What does the next potential mate sound like?
DING Time's up again.
Does the next one have a better song?
QUICKFIRE CHIRPS
DING
Nightingales have extremely large song repertoires, up to 250 songs.
And also they are able to produce really challenging
syllables and phrases, thinking of trill or bass elements.
So these are very fast, repeated single notes.
So this is remarkable.
The more complex his song,
the more beautiful it seems to the female.
But why? Does the female have an aesthetic sense,
as Darwin suggested?
Conny and her team set up an experiment to find out.
First, they recorded males singing at the beginning of spring.
Then they set up cameras to record nightingale nests
later in the season.
Male nightingales play a crucial role in feeding chicks.
What we found in the end was that there was indeed
a very strong correlation between his song
and feeding rates at the nest.
So it's like a promise that the males give to the females
to be good fathers.
So, for example, a male could be saying,
"Hey, there, I'm a healthy, strong man,
"I know this area and all the best feeding places very well,
"so come settle down and mate with me."
Females, Darwin said, chose the males with the most beautiful
songs, and my third recording has demonstrated why.
Better singers are better fathers.
Songs can be a promise of devoted parenthood.
There are some songs that it's impossible for me
to imagine life without.
ROBIN SINGS
Songs that accompany our daily lives.
It's one of the most characteristic sounds, and to my ear
is one of the most delightful of the English winter -
the song of the robin.
These are the songs that Charles Darwin
would have listened to as a boy.
And much of our research into song has centred on British species.
Indeed, for much of the last century, we thought birdsong
originated here in northern latitudes.
But what if Darwin had been raised on the other side of the world?
Would his theories about song have been different?
CACOPHONY OF ANIMAL CALLS
The forests of Australia.
Out here, scientists are in the process of changing
many of our old ideas about song.
HOOTING CRY
They found fossil and DNA evidence of early songbirds,
which show that this, in fact, is where song began.
It was here in Australia that the ancestors
of all songbirds first evolved.
Song number four is from one of the original songbirds'
most remarkable descendants.
And it's one that amazes me every time I hear it.
QUIZZICAL WHISTLES
It was recorded in the forests just outside Melbourne,
and it was the first time that wild birdsong had ever
been broadcast in Australia.
BIRD CALLS
The song of the lyrebird, in my view, is one of the most complex
and beautiful in the whole of the natural world.
And what gives it its complexity
is the talent that a lyrebird has
for mimicry.
ON RECORD: Crimson parrot.
BIRD CALLS
The kookaburra.
BIRD CALLS
The descendants of that lyrebird, I'm happy to say,
are still singing in those forests,
and I've been lucky enough to listen
to one of them myself.
It was the 1990s when the BBC series Life Of Birds took me to Australia.
I wanted to film a lyrebird who was the most astounding mimic.
To persuade females to come close and admire his plumes, he sings
the most complex song he can manage,
and he does that by copying the songs of all the other birds
he hears around him,
such as the kookaburra.
KOOKABURRA CALL
He can imitate the calls of at least 20 different species.
He also, in his attempt to out-sing his rivals, incorporates other
sounds that he hears in the forest.
CLICKING
That was a camera shutter.
And again.
And now a camera with a motor drive.
CLICK AND WHIR
ALARM BLARES
And that's a car alarm.
And now the sounds of foresters and their chainsaws working nearby.
BUZZING
SAWING
Since this remarkable clip was broadcast, millions of people
have watched it online.
Scientists have discovered a lot more about lyrebird song
since that recording was made.
That particular bird was accustomed to the presence of human beings
nearby, but much wilder birds produce something
even more fascinating.
Sunrise, Sherbrooke Forest, today.
One voice in the dawn chorus
is louder than any other - the male lyrebird.
BIRD CALLS
It's the breeding season and they're busy trying to attract mates.
Clearing undergrowth from the forest floor creates
an arena for his mating display.
Once the stage is set, the show can begin.
CALLING
It's unlike any other in the natural world.
Since I heard this song,
scientists have analysed it and broken it down into parts.
Song A comes first.
CLICKS AND WHISTLES
Now song B, a loud low shriek, which alternates with song C,
a quiet, very soft clicking sound.
A female arrives.
But no, she loses interest.
What he does next will need to be even more impressive.
Few have analysed the grand finale of the male lyrebird song
more intensively than Dr Anastasia Dalziell.
She and her team were the first ones to film it properly.
We thought no-one's going to believe us until we've actually filmed it.
It's really not like anything else that has been described previously
in birds or any other animals.
It was by studying the recordings from their remote camera
that the team were able to understand the real secret
of the male lyrebird song.
And it's this footage together with our own that enables us to show
this remarkable behaviour on television for the first time.
Having sung A, B and C and been rejected, the male now
begins Song D.
So this final song,
it's the sound of a flock of small birds mobbing,
reacting to a stationary or a hidden predator like a snake.
And this was totally bizarre.
So why is he imitating a flock of birds?
Well, a predator means danger.
So at the sound of an alarm call, the female freezes.
The forest is no longer a safe place.
Now the male takes advantage of her panic.
He jumps on top of her to mate.
It's hard for us to see her under his feathers,
and it's hard for her to see out from under them.
He's doing everything he can to disorientate and confuse her.
The male is actually telling her a big fib -
don't leave me because out there, there's a hidden predator
that you haven't seen.
To put it another way, it's like saying,
"Baby, it's dangerous outside.
"Come back here with me where it's nice and safe."
The lyrebird is, in fact, a bird that tells lies.
His song is an acoustic illusion.
Up to now, scientists have thought
that song was an honest signal from the male.
But it seems song can also be manipulative and false.
scientist Victoria Austin is studying the female lyrebird.
What she's listening for
is something very few people have heard.
So what I'm doing now is just preparing my recorder
because we're about to head to a nest and we're hoping to be able
to record the female lyrebird that resides in that area.
The female lyrebird is the opposite of her flashy mate.
She's secretive.
When she is seen, she's often mistaken for a juvenile male.
To most people, she's invisible,
but Victoria knows how to find her.
This old nest suggests that she may be nearby.
And there she is.
This rarely heard sound is her whistle song.
CALLING
In Darwin's theory of sexual selection,
males sing to attract females, and females drive the evolution
of song by preferring ever more complex songs.
The females themselves do not sing.
Yet here we are listening to a female lyrebird singing.
So what is the function of her song?
Well, the female raises her chicks alone.
The male plays no part, so it's extremely important
for her to maintain her territory and the food within it.
She uses song to let everyone know that it's her patch.
CALLING
And Victoria is also researching
whether song helps her in other ways.
In the last few years, she's been recording their songs
across the Blue Mountains.
This is one of them - a female mimicking a goshawk.
BIRDSONG
It's very accurate.
If you were to play this call alongside an actual goshawk,
it'd be very difficult to tell the difference, if you were able
to tell the difference at all.
So what is the purpose of this perfect impersonation?
She's using it to deceive predators into thinking she's more dangerous
than she actually is.
She is just as talented as the more famous male.
So the biggest purpose of what we're doing working
with these female lyrebirds is to dispel this long-held myth that only
recently was shown not to be true,
and that is the idea that female birds don't sing,
or that it's very rare.
And that's just simply not the case.
This surely challenges Darwin's theory,
as does my next revolutionary song.
My fifth song was also recorded in Australia.
It, too, like the song of the female lyrebird, has rarely been heard.
It's important because its existence changes our idea
of what song actually is.
BIRDSONG
This is a fairly common Australian bird called a fairy wren.
We filmed these birds for a BBC series back in the 1990s.
We went there to film it because it's extremely promiscuous.
Both male and female will mate with many different partners.
But what few people realised at the time, and I certainly didn't,
was that it's not just the male that sings.
The female does, too.
This is Canberra Botanical Gardens.
Professor Naomi Langmore was the scientist
who made our fairy wren recording.
She was one of the first to realise the significance of female song.
The male fairy wren, with glorious, iridescent blue and striking
black plumage is rather difficult to miss.
So where is the female?
Well, not at the top of a perch like the male,
but instead here, hiding in the bushes.
She is comparatively rather dull - a drab brown.
Because females are often less flashy and eye-catching than males,
it's very easy to miss female song.
BIRDSONG
But sing she does.
Just as male song is used in competition with other males,
female song seems to be in competition with other females.
But why didn't we hear her before now?
Is it really just because she's less noticeable than the male?
In the history of the study of birdsong,
most research was done in the northern hemisphere, in Europe
and North America, and in those regions,
female song is comparatively rare.
And so researchers working in those regions generalised
from what they were observing in their local birds and assumed
that male song was the norm throughout the world.
A male-biased view of birdsong had,
to an extent, deafened us to female song.
So when I was doing my research, it was basically assumed
that it's the male that sings and the female doesn't.
Maybe that's because most of the scientists were males
who were studying birdsong.
But now there's a new generation of female scientists coming through
studying birdsong all around the world
and discovering that actually female song is very common
and occurs in more species than not.
And it's only now that they're properly being heard.
Naomi and her colleagues have discovered that in 64%
of all songbird species, females sing.
And that, in the distant past,
the ancestors of all songbirds
would have had both male and female singers.
When birdsong began, perhaps all female birds sang.
So why don't all female birds sing today?
The answer is migration.
Male migrants like the nightingale arrive in their breeding grounds
before the female. They set up and defend the breeding
territories, so the females don't need to sing.
In species that don't migrate, like the lyrebird and fairy wren,
then often the females will have their own territory.
And they will sing to defend it.
This female song challenges the way scientists have thought about
sexual selection for the last hundred years.
This recent discovery is a paradigm shift.
It's extremely exciting,
and it really forces us again
to reconsider what we think of as birdsong.
Birdsong was fundamental to the formulation of Darwin's theory
of sexual selection,
and the discovery that females sing as well
makes us challenge that theory.
Because our perception of birdsong has been biased
towards the northern hemisphere,
we have been unaware of some of the most thrilling bird songs
on the planet, but that view is changing.
Our understanding of song is continually developing,
and all the time we're learning new things.
It's a mystery that needs real research to unravel it,
and we're still learning.
How exciting it is to think of the discoveries
that are about to be made about birdsong.
This next ground-breaking recording reminds us just how thrilling
those new discoveries could be...
..because it revealed to us an entirely different world of song.
Few animal songs are more beautiful than the ones that are recorded
on this disc, and yet had it not been for recent technological
advances, we would never have known that such songs existed.
The waters off the coast of Bermuda.
US Navy engineers are using underwater microphones called
hydrophones to listen for enemy submarines.
This is what they pick up.
LOW GROWLING
It's not a submarine or indeed any kind of man-made noise.
I'll always remember the first time I heard those songs.
It brought back to my mind the stories of sailors
in the old sailing ship days
out at sea in their bunks,
hearing those wonderful, eerie sounds resonating through the ship.
It didn't come, of course, from a mermaid, but something perhaps
even more extraordinary - a gigantic creature weighing many tonnes.
A whale.
WHALE SONG
Almost unbelievably, this was the first time that anyone had ever
identified the sound of a whale.
When biologist Dr Roger Payne heard it, he was thrilled.
It was back in 1967 about that I met a fellow named Frank Watlington,
who became a great friend,
and he played a sound to me of humpback whales.
WHALE SONG
It was the most beautiful thing I had ever heard from nature.
The first time I ever went swimming with a whale that was singing,
it's such an incredible experience, it's completely shattering.
It feels like, when you get close to one, that something
has put its hands on your chest and is shaking you
until your teeth rattle.
My first thought was, I wonder if I can stand this, I wonder
if this is actually going to kill me somehow.
The question was, would we call these sounds songs?
Some were short, like birdcalls,
but others were longer,
some up to half an hour.
Speeded up, this is what they sounded like.
HIGH-PITCHED SONG
They sounded like birdsong.
Roger called them songs.
In the late 1970s, I too went swimming with humpback whales.
I remember seeing this creature below me and then hearing its song.
EERIE WHOOPING
It was thought they sing for the same reason as birds -
males singing to rivals and potential mates.
But no-one has ever seen a female listening.
In truth, no-one really knows why whales sing.
But one thing is certain - the sound of their song saved them from us.
In 1970, Roger released an album called Songs Of The Humpback Whale.
At the time, we had been killing whales,
mainly for their oil, for centuries.
We were very close to exterminating them out of sheer greed.
Then we heard their song.
Whole bunches of people in several countries began making organisations
to save the whales and the Save the Whales movement was born,
and in many ways that was sort of the beginning
of the conservation movement.
The conscience of the world was woken by this song of the whale.
We heard it just in time to save them.
ECHOING SHRIEK
But for my next and final singer,
there was no such reprieve.
BIRDSONG
There are few songs more haunting than this.
It's a male Hawaiian 'o'o bird calling for a mate.
But is he singing into silence?
Habitat destruction
and the introduction of invasive species have decimated
many Hawaiian songbirds, including the 'o'o.
It may well be that by the time this recording was made,
there were no females left alive.
It's the sound of a male singing for a mate who no longer exists.
The 'o'o has since been declared extinct.
He was the last of an entire bird family found nowhere else on Earth.
Now gone.
There is no more dramatic reminder of this loss than this sound.
BIRDSONG
And how many more songs have we lost in other parts of the planet?
Here in Britain, it's estimated that 38 million birds
have disappeared from our skies in the last 60 years.
One in five gone.
Climate change, habitat deterioration
and the resulting decrease in food and other resources
are thought to be the main factors
behind this catastrophic decline.
It's now up to us to decide how many more songs
we will allow
to fade into silence.
These songs enrich our lives, too.
They're surely amongst the loveliest in the universe.
And without them, our lives would truly be impoverished.
And what is lost when the songs fall silent is more than just
an enchanting operatic backdrop to our own lives,
because for the creatures that sing them, songs are far more than that.
They are a weapon of war...
..a serenade, a promise of parenthood, a daring deceit...
..or perhaps something even more astonishing
that we are yet to discover.
Each one a marvellous example of the spectacular survival strategies
that animals have developed in order to stay alive.
WHALE SONG
That is why I'll never cease to wonder at
the beautiful sounds
we call song.
CHIRPING
Few sounds of nature are more beloved by this nation
than that of the nightingale.
And there's one more recording of it that I have memories
of listening to as a child.
It was made by the BBC two years before I was born, in May 1924.
It's a cello accompanied by a nightingale.
In this country, it was ground-breaking.
It is, in fact, the first live broadcast of any wild animal song.
The idea came from a celebrated cellist called Beatrice Harrison.
RECORDING: One night when I'd been playing for hours,
I suddenly heard the note
of the most heavenly bird,
and it struck me how lovely it would be if he could be broadcast.
The nation held its breath while Beatrice played.
It was the first time that the wild world of nature
came straight into your living room.
Perhaps a million listeners tuned in to that first broadcast.
It was so popular, the BBC made it an annual event.
The performance became so celebrated that Beatrice was asked to recreate
it for a 1943 film with Sir Laurence Olivier.
CELLO PLAYS
BIRD CALLS
It was far from the first time, of course, that the nightingale
had made a cultural appearance.
The nightingale has inspired poets and musicians for ages, and perhaps
the most famous poem of all is by John Keats.
Thou was not born for death, immortal Bird!
No hungry generations tread thee down,
The voice I hear this passing night was heard
In ancient days by emperor and clown.
Keats wrote those lines in Hampstead in London,
but he wouldn't hear a nightingale there today.
There are no nightingales in London now.
In fact, we've lost over 90% of nightingales in this country
in the last 50 years.
What a tragedy.
The causes are still not fully understood...
..but habitat deterioration probably played a significant part.
In one small corner of Britain, however, there is a place trying
to provide the nightingale with a safe haven.
The Knepp Estate in West Sussex - 3,500 acres that was once farmland.
But the soil here wasn't suited to modern-day intensive agriculture.
Since 2001, it's been left to nature.
There aren't many rewilding projects in Britain as pioneering as this.
Wildlife now thrives here...
..including some of the country's rarest species.
CUCKOO CALL
This, for many of Britain's best-loved songbirds,
is an ideal place for shelter and food.
The nightingale is one of many species found at Knepp.
Here, dense, almost impenetrable thorny scrub
provides their ideal nesting site.
Today, it's late spring and one nest of chicks is being ringed.
This makes it possible to gather vital information that can help
monitor population numbers.
There are estimated to be more than 40 nightingale territories
in this area of the estate.
Back when it was intensively farmed,
there were only nine.
Few places in Britain have nightingales increasing
in such numbers.
It gives us hope, perhaps, that the British countryside
could once more be filled with the nightingale's
beautiful and iconic song.
How wonderful it would be if each of us could say we've heard the songs
of the Earth and we've saved them.
BIRDSONG
WHALE SONG
BIRD AND WHALE SONG