Natural World (1983) s15e01 Episode Script

Somewhere on the boundary between the Atlantic Ocean and the Caribbean, a bull sperm whale emerges from the kingdom of the deep.
At 30 tonnes, he's a giant among toothed whales, and the most formidable predator on the planet.
Once persecuted to the brink of extinction, sperm whales are now returning from the abyss.
The huge whale is not alone.
It's being tracked by a team of researchers, led by Jonathan Gordon from the University of Oxford.
Coming up on him.
Still ahead, but it's very loud.
Observing deep-diving creatures on the high seas is a challenge, but their yacht, the "Song of the Whale", is equipped for the job, and Jonathan and his collaborators in other parts of the world are discovering the nature of the least known of the great whales.
"Song of the Whale" makes an excellent platform from which to make sightings.
When under sail, she makes little noise, and from the top of the mast, it's possible to scan a long way towards the horizon.
The ocean is vast, and any surface activity might lead Jonathan and his team to schools of whales.
They've already sailed across the Atlantic.
That was when they intercepted the large male.
Indeed, they were all heading the same way - towards Dominica.
This island has long been known as one of the favourite haunts of the sperm whale.
Dominica plunges steeply to the sea bed, over 1,000 metres below the surface.
It's mostly female sperm whales with young that come to these deep, warm seas.
The females form the basis of sperm whale society, and they rarely stray far from their breeding and calving areas, such as this.
Reaching up to 12 metres long, they're much smaller than the fully grown males.
Unlike other great whales, the cows are quite gregarious and live with their calves and immature bulls in groups of between 12 and 50 individuals.
With so many females around, the defenceless young may be safer when their mothers go diving for food.
In the past, whales were pursued by people with commercial, rather than scientific motives.
At the beginning of the 19th century, numerous ships sailed out of New England to slaughter whales.
The sperm was by far the most valuable After all, in those days, whale oil lit the lamps of the Western world and lubricated the wheels of industry.
Attacking some whales was risky.
Belligerent sperms frequently retaliated, with disastrous consequences.
Such encounters inspired Herman Melville's classic yarn of Moby Dick, a malicious white sperm whale that was continually "athirst for human blood".
He turned the tables on his pursuer, Captain Ahab, and destroyed him and his ship.
Open-boat whaling continued in the Central Atlantic until 1987.
The seafarers from the Azores knew how dangerous sperm whales could be when harpooned.
When injured, the whale could take off, towing the boat at 15 knots on what was called a "Nantucket sleigh ride".
Such was the destructive power of the flailing tail that they called it "the hand of God".
Nowadays the whales enjoy a measure of protection, and the researchers can work the old whaling grounds without disturbance.
The sperm whales' restless routine continues regardless of whether it's day or night.
A few years ago, Jonathan could not have tracked the whales in darkness.
But thanks to the development of the hydrophone, nocturnal tracking is now a practical proposition.
The boat trails a pair of underwater microphones.
RHYTHMIC CLICKING These pick up sounds made by vocalising whales.
CHIRPING CLICK Specially designed equipment lets the team pinpoint the direction of the calls with astonishing accuracy.
What have we got, then? I can still hear the sperm whales.
Have we got that male? Yeah.
Richard, they're still here.
We can get going.
OK.
Throughout the night, the research vessel will shadow the whales, which follow a surprisingly straight course, and cruise at the same speed for hours on end.
By moonlight, the Caribbean Sea changes character.
At night, creatures from the deep visit the surface.
Squadrons of squid, themselves food for sperm whales.
Meanwhile, hundreds of metres down, the huge whales are taking their fill.
After a busy night, "Song of the Whale" is drifting off the west coast of Dominica.
Something puzzling has happened - the sea has gone silent.
The directional hydrophone is so sensitive, it can detect sperm whales calling up to five miles away, so it's unlikely that they've given Jonathan the slip.
In fact, they're almost beneath the hull of the boat.
And they're quiet because they're sleeping.
Why they should rest upright, or lie motionless, is still a mystery.
Perhaps it's their way of avoiding detection.
Like other marine mammals, they seem to sleep at different times of the day, and do so with their eyes closed.
Now, they're beginning to stir.
CLICKING In a matter of minutes, they can be miles away.
With no wind to fill the sails, Jonathan and his crew must use the engine to keep up with the pods of moving whales.
CLICKING Sperm whales communicate with each other by producing and receiving pulses of sound.
One of Jonathan's research projects is to decipher the function of these clicks.
They seem to be used for individual identification, and for keeping the pods together.
About midday, the whales slow down, and small groups start to congregate.
This is what Jonathan has been hoping for, because it might be the prelude to some important behaviour.
The females are accompanied by their offspring of various ages and indulge in a great deal of bodily contact.
This rubbing must surely be an expression of mutual recognition, and a way of renewing their social bonds.
The calves depend upon milk for a year or so.
The mothers find it easier to suckle them away from the rest of the group.
These bouts of serious socialising raise the possibility that the animals within the groups are closely related to each other.
Perhaps the females are sisters, or half-sisters, and their daughters.
An opportunity arises to check the theory.
The whales continually shed pieces of skin, and one of the researchers attempts to collect some.
As the skin sloughs off, it is consumed by remoras - sucker fish that live on the whales.
CLICKING The persistent body rubbing that takes place when whales meet sometimes loosens great strips of skin.
Once collected, the fragments from different individuals will be taken back to the laboratory for genetic analysis.
The results will reveal the extent to which the whales are closely related to each other - or not.
After the samples are taken, there are plenty of bits left to provide meals for camp followers, like dorado.
When the whales start to feed, the groups disperse.
The very young ones lack the endurance to dive with their mothers.
This presents the parents with something of a dilemma.
If no "baby-sitter" is available, the mothers must head into the depths, leaving their offspring behind for up to an hour at a time.
Although a newborn whale weighs a tonne and is four metres long, it can still fall victim to the "wolves of the sea" - sharks.
Even when the mother is hundreds or even a thousand metres below, parents and offspring call to each other and a cry of alarm from a youngster alerts adults to potential danger.
The returning mother knows exactly where her calf is.
If she's angered, she can go on the attack.
Her lower jaw may look narrow but it's quite capable of biting a rowing boat in two.
The old bulls and some younger males have quite different lifestyles.
They are solitary nomads.
For the most part, the bulls stay in cooler regions.
But at certain times of the year, they associate with the cows and their calves.
In the Caribbean, the big males appear so infrequently that Jonathan gives them names.
There's a big male a really big male.
It's Hal again - it's the one with the white head.
You'd hardly believe they were the same species.
That great big head Hal's got Look at that blow! A really powerful blow.
I wonder if we can hear clangs.
Can you get a direction to see if this guy's clanging? The mature males announce themselves with a characteristic sound - a loud clang, or click.
CLICK! Big Hal carries on his forehead the scars of battles with rival bulls.
He's on his way once more to find the females.
MANY CLICKS Clearly, they're excited by his presence and move in his direction.
CLANG CLANG CLANG OTHER WHALES CONTINUE CLICKING He doesn't rely solely on his penetrating clicks to signal his arrival.
No-one properly understands the significance of tail-lobbing, but whenever whales start to socialise, they frequently slap the water with their flukes.
Within a short time, several family groups have joined up into an exceptionally large gathering of 40 or so whales.
CLICKING Soon, big Hal is in the thick of them.
CLICKING CLANG Like a submarine, he depends on acoustics, using sound to navigate and picture his surroundings.
His colossal head, which accounts for a third of his length, contains the biggest of all animal brains, an immense sac of oil, and the mechanism for producing a wide range of sounds.
But this sound is not for navigation.
He adopts a head-down position and clangs for all he's worth.
SERIES OF LOUD CLICKS This may be Hal's way of attracting a mate and showing the immature males who's boss.
CLICKS AND CLANGS Hal's arrival has caused quite a commotion and the audience of females and their calves join in the chorus.
MANY CLICKS Another young bull is singing, 20 metres down.
Within a short time, there are whales sounding off at all depths.
Even the calves react to the clamour.
That lower jaw may be an important sound receptor, conveying information to the enormous brain.
Although they're too young to mate successfully, the young males become aroused by the presence of so many females and calves.
No-one knows quite what's going on here, but bouts of sexual exploration among the young bulls are frequently observed on occasions like this.
For the adolescent males, such precocious behaviour might be a sign that they won't be staying with their families much longer.
These sessions often result in the release of semen into the sea, so they are almost certainly of no reproductive significance.
After an hour or two, the socialising comes to an end.
Big Hal is getting hungry.
His sonar enables Jonathan's team to follow his progress, and to imagine what occurs on his incredible trip into the abyss.
As a diving mammal, he's unrivalled.
From the echo of his calls, he'll picture the layout of the sea bed and the whereabouts of his prey.
With heartbeat slowed to about one-third its normal rate and blood diverted to the brain and vital organs, he descends in search of food.
At a depth of between 300 and 1,000 metres, the whale echo-locates his prey by the thousands, for big whales have huge appetites.
After nearly an hour, the urge to breathe drives Hal to the surface, where "Song of the Whale" is waiting for him.
Males leave their family groups when they're about six years old.
Schools of half-grown bulls migrate to high northern or southern latitudes where they'll find the off-duty breeding bulls.
During the latter years of mechanised whaling, the males were especially targeted because of their size.
The killing was so intense and prolonged that the big bulls were almost wiped out.
So much so that they're rarely seen, even to this day.
Since the ban on commercial hunting in 1988, sights such as this are a thing of the past.
The growing males and off-duty bulls concentrated in particular places capable of supporting their vast appetites.
One of them was off the South Island of New Zealand, in the bountiful sea bordering the Kaikoura Peninsula.
A commercial whaling industry was once located here, because of the presence of numerous large sperm whales so close to the coast.
There's virtually no socialising here, for the whales have only one thing in mind - feeding.
The Kaikoura Peninsula juts out into very deep water, so the whales find food very close to the shore.
In New Zealand waters, the bulls are busy growing and building up their reserves after swimming thousands of miles from the places where they were born.
They won't reach sexual maturity for another two decades, when they're almost 30 years old.
Those tail flukes are an impressive four metres across.
The reason for the fertility is revealed by the colour of the sea.
Nutrient-laden water wells up from the deep and mingles with warmer currents, enriched by run-off from the land.
For the past six years, Steve Dawson and Elizabeth Slooten have been discovering a great deal about the behaviour of the Kaikoura bulls.
Large schools of dusky dolphins - themselves little toothed whales - reflect the high productivity of the southern ocean.
DOLPHINS SQUEAK As soon as Steve and Liz start their observations, the dolphins disperse.
Liz is particularly accomplished at tracking sperm whales.
Great.
I can hear three whales, Steve.
Excellent.
She's one of the few people capable of following them when feeding a kilometre below the surface.
Almost certainly, the New Zealand whales are down in the realm of that other deep sea giant - the giant squid.
But up above, there's evidence that the whales' basic diet is composed of much smaller creatures.
BIRDS CRY Sperm whales are careless feeders.
Some of their injured or half-digested prey often floats to the surface.
Can you reach it? I think we're drifting on to it.
Those Cape Pigeons are going for it.
Can you reach it? The whales thrive on huge quantities of squid about a metre long.
Can you see what kind it is? Looks like an arrow squid One had the remains of 30,000 squid beaks in its stomach.
.
.
That is a shame.
Steve and Liz try to get close, to identify every whale.
Here we go.
Got some slow clicks, so it could be up any minute now.
What side of the boat do you expect it up on? That side.
Not too far away.
OK.
Go on.
I'm not hearing anything now - should be up soon.
I'm sure it's Popsickle - that nick on the trailing edge and the other one on the leading edge.
He's really unmistakable.
He's a nice steady clicker - easy to track.
In the six years they've known Popsickle, he's grown three metres.
Now they manoeuvre for a photograph, but are careful not to alarm him.
Their technique is to keep the engine running so the whales get used to the noise.
Only when the whale breathes out is the prop engaged.
Presumably, the rush of air through his nasal passages masks the sound of the small boat approaching from the rear.
Liz and Steve maintain a meticulous photographic record of the whales.
The only portrait of any use for future recognition is of the tail, because the nicks and tears on the trailing edge are permanent.
OK.
I'm on frame 27.
27.
OK.
I think this is ID film number two.
OK.
By this painstaking research, they've recorded hundreds of different sperm whales.
Many, like Popsickle, have been here on and off for several years.
Others are transient visitors.
At any one time, there may be about 80 in the vicinity of Kaikoura.
Most of them are adolescent bulls in their mid-teens to mid-twenties, avidly feeding in the race to become sexually mature.
Now and again, the largest of the Kaikoura whales will head north, to where the females are located.
900 miles west of Portugal lie the Azores, an island archipelago that rises from the mid-Atlantic ridge.
This is another breeding area for sperm whales, and a favourite location for whale-watchers.
The "Silvery Light", built over a century ago, when whaling vessels relied upon wind and sail, has just arrived from England.
Carolyn Sherie and skipper David Redhead regularly lead expeditions to these waters.
On board is Jonathan Gordon's brother Tom, who's here to try out something new.
The "Silvery Light" steers for the so-called "honey hole", where groups of sperm whales often gather.
Bottlenose and common dolphins are heading for the same area.
Suddenly the ocean is alive with the sound of cetaceans - CLICKS AND SQUEAKS the whistles and squawks of dolphins and regular clicks of the sperm whales.
For some reason, the dolphins harass the female whales and their calves, which at first close ranks.
SQUEAKS AND CLICKS CONTINUE Despite their great size and strength, the whales seem unnerved by their smaller but highly manoeuvrable cousins.
This time, the Leviathans of the sea change course, turn on their flukes, and flee! Why the dolphins choose to see off the whales is difficult to imagine.
Perhaps they're just being playful, or mischievous.
For the most part, whales and dolphins share the seas without signs of conflict.
Since the sperm whales have been put to flight by the dolphins, the "Silvery Light" heads offshore.
A sudden surprise - a pair of "white sperm whales" - turn out to be Risso's dolphins.
Eventually, a family of sperm whales is spotted.
They've been active all morning but are now resting in characteristic "logging" formation.
Tom decides that this is a good situation to try out a method of approaching them based on that used by the open-boat whalers of the Azores.
He's going to row.
Oars are quiet, and apparently enabled the whalers to sneak right up to their quarry.
How will the whales react to this intrusion? With Carolyn in the bow, Tom approaches closer than he's ever been in a motorboat.
What's that in his mouth? It must be a piece of plastic.
There's a big piece of plastic.
Spit it out.
A lot of debris collects where currents meet.
Plastic bags are virtually indestructible.
They're often mistaken for jellyfish.
When swallowed, they can block the digestive system.
CLICKING This one has a heavy-duty fishing line snagged in his jaws.
Although these ocean triggers make use of the flotsam for shelter, sperm whales also drift in these flows and swallow all kinds of rubbish.
A fresh but fatally bitten octopus floats by - a crumb from the whale's feast.
It's well over a metre long.
Although rarely found alive, this octopus is wide-ranging and occurs down to 2,000 metres.
The damage inflicted by the sperm whale's teeth is clear.
The whales show no particular concern at Tom and Carolyn's presence.
Perhaps the rubber dinghy's soft exterior resembles the body of another whale.
See them coming to the surface now.
There's its mouth.
Look at this! Oh, my God, this is close! It's too close, Tom! SHE LAUGHS They don't mind us, do they? CLICKING Being as close as this, they make an interesting discovery - the whales can vocalise with their foreheads raised clear of the water.
CREAKING CLICKS It's very Once young whale decides to investigate and grabs the tow rope.
Tom, you can see he's got a crab on his head! Please don't blow! SHE LAUGHS That was close.
That was close.
It was friendly, though.
He could have tipped us out if he wanted to.
Gave me a shock! Amazing.
Enjoy it? Not really! No, I was a bit scared actually.
Will we do it again? Yeah, go on! Tom is astonished at how gentle and trusting the whales have been.
But his discoveries have not come to an end.
There's an even greater surprise in store for them both.
A white sperm whale - a baby Moby Dick.
Wow! He's looking at us! White sperm whales are exceptionally rare.
Only a few have been spotted this century.
Little Moby isn't very old - on his flanks he still bears crease marks, made when he was curled up in the womb.
Tom can't resist the temptation to obtain a better view of Little Moby.
The females appear to be in a mellow mood, unconcerned about the dinghy that's lurking around their group.
But the sperm whale's formidable reputation makes Tom cautious.
There are many well-authenticated stories of them attacking people.
One fisherman was swallowed by a large bull.
Unlike Jonah, he didn't escape! Even calves have chased experienced divers out of the water.
The powerful males have the potential to be very dangerous indeed.
Luckily, there are no big bulls in sight.
In the end, Tom feels confident that it's safe to go swimming.
The females are very protective of their young, and Tom is unable to find the white calf.
Suddenly, there it is.
Little Moby explores the stranger who has suddenly entered his world.
How was it? That was fantastic.
That was amazing.
Looked great.
I've never had a swim like that.
So close, so many of them Did you see the white one? Yeah.
I've hopefully got some photographs.
There are strong pressures for the resumption of commercial whaling, so Little Moby's survival is in the balance.
Only if he's allowed to live for half a century will he become a magnificent whale the size of Hal - a real Moby Dick.
We would once have slaughtered a whale like this without a thought.
Now, an enlightened, more respectful relationship has begun to emerge, through watching whales.
It's yielding riches - illuminating not our lamps, but our sense of wonder at the creatures with which we share the world.
BBC Scotland - 1996