Giant Lives Ocean Giants


Giant Lives

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This is a blue whale, the largest animal on the planet.

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In fact, the largest animal that has ever lived.

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It's 100 foot long and weighs nearly 200 tonnes.

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For millions of years, these giant whales

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and their super-intelligent cousins, the dolphins,

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have ruled the world beneath the waves.

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Sadly, our relationship with them has not always been a friendly one.

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In the past, we persecuted them.

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But today we are reaching out to them

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and experiencing a sense of wonder that's hard to explain.

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As we explore the seven seas, we'll come face to face

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with the world's most extraordinary whales and dolphins.

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Uncovering their secrets

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alongside the scientists

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who dedicate their lives to understanding them.

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The great mystery is, what are the whales doing here?

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These killer whales demand respect. They've taken out a minke whale

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that probably weighs more than ten tonnes.

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I think we could talk to dolphins within five years.

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Sharing these breathtaking encounters,

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two of the world's top underwater cameramen.

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I've waited a long time to see a blue underwater,

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and that was just magic.

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Fantastic, today is the best day of my life.

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Whales are born to be big.

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Even this newborn baby weighs over a tonne.

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So what is it like to live your life as an ocean giant?

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Part of our attraction to whales has always been their gentle nature.

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But we are beginning to discover a different story,

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one spiced with sex and violence.

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Every spring thousands of humpback whales are drawn to Hawaii,

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the world's most remote island chain,

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to do battle.

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A scientific team heads out over the tropical seas of Maui,

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for a bird's-eye view of one of nature's greatest showdowns.

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Gangs of humpback whales posture, ram, and can even kill each other.

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So what has driven these giants to fight?

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The answer to this question needs

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a close-up view of the action from underwater.

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Jeff Kalbach has spent 15 years watching fighting whales,

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trying to make sense of their belligerent behaviour.

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OK, she is ready to go.

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He's joined by ex-Cousteau cameraman Didier Noirot,

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who's hoping to find more clues

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by going right into the thick of the action.

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Humpbacks are my favourite whales.

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I have filmed them many times before

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but there is one thing I'm really keen to see,

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is to see the fight of the males.

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It's going to be very dangerous,

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you can be hit by the tail end. I guess you can die.

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They go so fast underwater despite their size,

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and that's going to be, like, a challenge for me.

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There's news of some action a mile offshore.

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See that pectoral fin, the white?

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Now it's going up, rolling over.

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A female humpback announces she's here, and she's ready to mate.

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These fin slaps can be heard a mile away.

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And almost immediately a gang of suitors is headed her way.

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One, two, three, four, five, there's definitely six, seven.

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Oh, big guy.

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Before long, she's surrounded by male admirers.

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To help her choose the strongest mate

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she sets the ultimate fitness contest.

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She sets off on a marathon swim

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with the pack of jostling males in hot pursuit.

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Each one is trying to win her affections

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by staying as close to her as possible.

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-All ready to go?

-Yes, exactly.

-We have to go.

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Underwater, the 40-tonne males might seem relaxed

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but the tension is building.

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They are already sizing each other up.

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These lustful rivals could do battle at any minute.

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Didier must stay alert.

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He can't risk diving with scuba tanks,

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as any dispelled air could be interpreted

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as a challenge by the males, who blow bubbles as a sign of aggression.

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Like now.

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Suddenly, the female comes into view,

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escorted by a bubble-blowing lead male, or "primary".

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It's a good start to the filming.

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There was the two animals right here

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and I could tell that wasn't the female or the primary

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so we were looking and then all of a sudden, Didier was like, ooh,

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he hits me and then right behind us was the primary

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coming with a bubble trail.

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-Bubble trail which I filmed.

-Yes.

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Jeff believes the escort uses bubbles

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to produce a 100-foot curtain

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to screen the female from other challengers.

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And, with lungs the size of a car,

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it's the biggest male that can expel the most air.

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This hot pursuit can last all day and cover miles of ocean.

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To stand a chance of catching the action the team must race ahead.

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Meanwhile, the competition escalates to explosive shows of strength.

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Look at that, he's riding contact with her, you can see his pec fin.

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The other animals are colliding into him,

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look at him pushing and shoving.

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See that fluke just flick over like this

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and he's diving down, charging at somebody, pushing somebody away.

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For the dive team, it's like jumping into six lanes of traffic.

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Testosterone-fuelled giants charge by at 20 miles per hour.

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A male upends into the crucifix block,

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a tactic to stop a rival in its tracks.

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As the violence intensifies,

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it becomes more dangerous for the rival whales and for the cameraman.

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A huge male charges straight for his bubble-blowing rival,

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ramming him off course.

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For Didier, it is the dive of a lifetime.

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-It was amazing.

-It was perfect, good dropping, thank you, good advice,

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we are just at the right time at the right moment.

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We saw the collision and then that male...with his, all his bubbles.

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Using his weight advantage, the bigger male takes the lead,

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but the female has yet to choose her mate and the marathon continues.

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Let's go. Let's go. Go, go.

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Then, suddenly, the mood changes.

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The female has vanished, perhaps having eloped with her chosen male.

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And without the object of their desire

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the heat has gone out of the battle.

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Minutes after duelling in the high seas,

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the males are caressing each other in a graceful ballet.

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And they stopped, they danced like a ballet, beautiful.

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How beautiful to watch them just moving and turning and touching.

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It was spectacular, very spectacular.

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Despite the scientists' best efforts,

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no-one has ever seen humpbacks mating.

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But everything points to the female choosing the biggest blowing

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and hardest hitting male to be the father of her young.

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It's not just humpback males for whom size really matters.

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Here, off the coast of Argentina, is the biggest whale orgy on the planet.

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In the sheltered bays of Peninsula Valdes,

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7,000 southern right whales

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come to mate, give birth

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and raise their young.

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Even for a veteran cameraman, it's an extraordinary spectacle.

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I have never seen that before. So many whales, so close to shore.

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It's probably the only place in the world you can see that.

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Right whales are huge, at least twice the sizes of humpbacks.

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Their tails alone match the wing span of a light aircraft.

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Unlike the aggressive humpbacks,

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male right whales are surprisingly gentle lovers.

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A 40-year project studying the lives of these extraordinary creatures

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offers a unique opportunity to get close to these gentle giants,

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and Didier can't wait.

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I love southern right whales,

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they are probably the friendliest of the whales,

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they are very approachable, they don't mind the divers,

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and here in Patagonia the water is very clear

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so I'm really looking to do something fantastic.

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Exploring the mating habits of these friendly whales

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is Dr Mariano Sironi.

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Tragically, it's their very friendliness

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that made them such easy targets for the early whalers

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and made them the "right" whales to hunt.

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Today, these giants are making a slow but promising recovery,

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thanks to conservationists like Mariano, and to their...

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..amorous nature.

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-You see the male in the right position under the female?

-Yeah.

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You can see the flipper of the male hugging the female,

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and they are belly to belly.

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Both sexes are very promiscuous,

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and the males are equipped

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with a particularly astonishing adaptation for mating,

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a pair of giant testicles!

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Their two testicles together can weigh up to one tonne.

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The testes of the right whale are 20 times heavier

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-than those of the blue whale...

-20?!

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..so, that's an indication of a very sexual species.

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Mariano is investigating the link

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between the size of a male's giant testicles

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and his chances of paternity.

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But making sense of this mass of writhing bodies at the surface is difficult.

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To complete the picture, Didier must get in the water.

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Let's go.

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With most whales, getting close to them is the challenge.

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With these whales, the problem is getting TOO close.

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WHALE GRUNTS

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WHALE BELLOWS SLOWLY

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They are so friendly that a diver must be careful

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not to be accidentally crushed by one of these 80-tonne giants.

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Underwater, it becomes abundantly clear

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that males not only boast giant testicles

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but that, at nine foot long,

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they have the biggest penis in the animal kingdom.

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And one which appears to have a mind of its own!

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When they finally mate, it's belly to belly.

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But this is just the start for the female,

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as she goes on to mate with the rest of the males,

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sometimes up to five or six at a time.

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After an hour of being spellbound by this extraordinary courtship,

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Didier's air finally runs out.

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-That was just fantastic.

-Good.

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What I have seen just now is the most amazing spectacle

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I have ever seen underwater.

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Ohh, that's good.

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Didier's intimate images of the mating

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will be invaluable to Mariano's study.

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By mating with a variety of males,

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the female ensures that the battle for paternity goes on inside her

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and not in the open seas.

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But it's still the biggest male

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that stands the best chance of winning that battle,

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because by having the longest penis and largest testicles

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he can flush out any competitor's sperm.

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For male southern right whales, size really does matter.

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And in 12 months' time

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this female will give birth to a calf

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that will inherit its father's strength

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and, most importantly, his size.

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But here, off the west coast of Mexico,

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it's the size of the mother that matters.

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These calm, safe waters are ideal nurseries

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for these playful grey whale newborns.

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For the first three months of their lives,

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when they're at their most vulnerable,

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the calves live in peace, feeding only on their mothers' milk.

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The calf has tripled in weight,

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but for his mother there's nothing to eat here.

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For her own survival, she must leave this safe haven

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and lead her calf on a perilous journey,

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the longest made by any mammal.

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From the barren waters of Mexico, they will swim 6,000 miles

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to the rich feeding grounds of Alaska.

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During its 50-year lifespan,

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a grey whale will swim over half a million miles!

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As they head north from Mexico, they hug the coastline,

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hiding in the murky shallows.

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But at Monterey Bay, California,

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they can take a short cut across the deep mouth of the bay,

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and that's a gamble.

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They're now exposed to attack.

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At dawn, a scientific research team heads out

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into the troubled waters of the bay.

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BELL RINGS, SEALS BARK

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John Durban is studying the attacks on grey whales.

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This is one of the most important ambush points

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for grey whales along the coast.

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The grey whales are coming to this point here

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and making the decision whether to tuck round in the bay

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or cut across to the other side and save them some time.

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But what could possibly take on a 30-tonne whale,

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especially one defending her calf?

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No-one knows better than underwater cameraman Doug Allan.

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Ten years ago, he filmed a ferocious attack in this exact spot.

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And what he saw was the oceans' top predator in action.

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Killer whales.

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The intensity of the battle has left a lasting impression.

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It's a very harrowing experience

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watching killer whales take down a grey whale calf.

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The calf tries so hard to survive,

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the mother does all she can, too.

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The killer whales are just so relentless,

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they harry, harry, and they will just take those two apart.

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A male killer whale is ten tonnes of pure power, a cunning mind

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and 60 teeth.

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The killers targeted the defenceless calf,

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its survival dependent on the strength and size of its mother.

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The killer whales' strength is in numbers.

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They launched coordinated attacks to outmanoeuvre the mother.

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But she wasn't going to give up her only calf without a desperate fight.

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Four times the size of her attackers

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and with thick skin protected by barnacles,

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she beat them back with deadly tail swipes.

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But the killer whales had chosen their victim well.

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The mother was neither big enough nor strong enough

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to withstand the onslaught,

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and the killers drove a wedge between mother and calf.

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Eventually, they drowned the isolated calf.

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After six hours, the battle was over,

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the mother exhausted, the calf killed and eaten.

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A decade on,

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John is waiting for this season's killer whale attacks to begin.

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-What's happening, John?

-They got killer whales,

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they're about a mile north of the ship over here, the Miller Freeman,

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and the killer whales were chasing something when they arrived, they've stopped.

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John is planning to attach state-of-the-art satellite tags

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to these killer whales for the first time.

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We've got a group of killer whales.

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As we're coming up we can see there are birds overhead,

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and you can smell a really strong fishy smell right now.

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That's a good indication they've killed recently,

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that's the blubber smell of a whale.

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The attack is over

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but the killer whales are now feeding on their victim.

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The bulk of the carcass is probably sinking

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and they're trying to hold it up,

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but we have seen a whale with a big chunk of flesh in its mouth.

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They're probably dismantling it right now.

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These killer whales just demand respect.

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The feasting whales offer John the best chance to secure a tag.

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Right under us here, it's going forwards,

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so if you go forward a little...

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To work properly, the tag must be positioned perfectly

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on the dorsal fin. John's aim has to be spot on.

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I'm waiting... OK, this one's coming up here.

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Perfect.

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Oh, yeah, look at that, it's flush.

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Just the tapes... the antenna looks good.

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With so many killer whales gathered in one place,

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John is eager to secure as many tags as he can.

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That's good, right there, it's good.

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When you tagged those whales they didn't flinch.

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That's the nice thing about small tags, it's an issue of scale.

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We're putting a 40-gram tag on a seven-tonne whale.

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They don't notice it.

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Now we've got some tags on,

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the signals are going to get pinged from the tags up to some satellites

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and we receive the signals on my phone.

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That'll allow us to track them over the next few weeks, hopefully.

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John can now track their movements and, critically,

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work out how often grey whales are attacked.

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Only one week later, some extraordinary results come through.

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Rather than wait in ambush in the bay,

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these killer whales have headed way up the coast.

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Here's Monterey Bay, to give an idea of the scale.

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It looks pretty small on this chart. The first group we tagged,

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in eight days now, no, further,

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have moved all the way to the top of this chart

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to Northern Oregon by the Umpqua River. It's over 700 kilometres.

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The hungry killer whales have had to broaden their search for prey

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way beyond Monterey Bay,

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perhaps because there are far fewer grey whale mother and calves

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undertaking their epic migration this year.

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It's highly likely that this immense migration,

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probably the longest regular migration of any mammal,

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is largely due to the threat of predation by killer whales.

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Grey whales may choose to breed in Mexico,

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thousands of miles away from their northern feeding grounds,

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simply to keep the calves safe from killer whales

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for as long as possible.

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After three months travelling,

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the grey whales finally make it to Alaska.

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The emaciated whales can now gorge themselves.

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Each day they sieve out over a tonne of shellfish from the muddy seabed.

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But it's only the largest, strongest and most determined mothers

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who can save the lives of their calves

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on this most gruelling of migrations.

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Further north, within the Arctic Circle,

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lives a whale three times the size of a grey whale.

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And it's grown massive for even more extraordinary reasons.

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As it stays in the Arctic all year round,

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it doesn't need to be big to survive lengthy migrations.

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And, protected by the maze of shifting pack ice,

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it has less to fear from killer whales.

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It's a bowhead whale,

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named after its enormous curved upper jaw.

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So, why is this whale so big?

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In eastern Greenland, a scientific team

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is attempting to unlock the secrets of this little-known giant.

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Cameraman Doug Allan has 30 years' experience

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filming at the frozen poles.

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Every time I come to the Arctic

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I think, "This is it, never again. Next shoot, Caribbean,"

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but there is something special about this that keeps pulling you back.

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In the last two centuries, bowheads were almost wiped out

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by commercial whalers, and are notoriously wary of humans.

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No-one knows this better than Doug.

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I think if bowheads had personalities they'd be a little bit sad.

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They've had such a lot of bad things done to them, were almost wiped out,

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but somehow I think they're coming back.

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They'd like to be friendlier

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but they just don't yet know how to trust us.

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WHALESONG ECHOES

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During the winter bowheads are impossible to track,

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but in spring they announce their presence with song.

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Eavesdropping on these mysterious giants is scientist Outi Tervo.

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She's one of the very few whale researchers prepared to tough it out

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in this brutally hostile part of the world.

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It's a "Whooo"...

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..and then a "Rughhhh."

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Outi suspects that these are mating calls

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and that the bowheads may be gathering somewhere close to breed.

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-Can I have a listen?

-Yeah, sure.

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Ah, "Whooo!"

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"Oooh," says the other one.

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"Oooh, I like you."

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Outi has never been able to see bowheads under the ice before

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and hopes that Doug's camera

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might offer new insights into the world of these secretive whales.

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Unfortunately for Doug, bowheads are the masters of concealment,

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able to hold their breath for up to an hour and a half.

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To make matters worse, the elements aren't exactly inviting.

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Brrrrrr!

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It's minus 20 degrees Celsius

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and Doug hasn't even got in the water yet.

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But at least there's a whale!

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She just heard me coming, I think.

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Bowheads are remarkably alert to danger.

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One small splash and this one simply melted away.

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The only hope is for a whale that is a little less skittish.

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Gosh, these whales... Gee, they're hard to get close to.

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As the game of cat and mouse continues, the Arctic weather closes in.

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Even with his insulated dive suit

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Doug is close to hypothermia after just two hours.

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-LAUGHING:

-I must be mad.

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But how do bowheads survive this cold?

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It's all to do with being a giant.

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The bigger and rounder the body,

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the better it is at retaining heat.

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Wrapped in 50 tonnes of insulating blubber,

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these whales are the fattest animals on the planet.

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Indeed, half their entire body weight is fat!

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The team continues to try to film the bowheads underwater,

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this time using a pole camera.

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For the whale, this method of filming may be less intrusive,

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and for Doug, well, it's just a little bit warmer.

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Hold it there, I can see a fluke.

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That was the first underwater shot of the bowhead.

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I'm sure we can improve on it, but at least it's a start.

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Already they're discovering something distinctive about these creatures.

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The footage reveals a patchwork of markings

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all over the whale's body.

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Bowheads use their backs to break through the ice

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to create vital breathing holes,

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permanently scarring their skin in the process.

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These patterns are as unique as fingerprints

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and help identify each individual whale.

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Nice shot, nice shot.

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With the whales so close,

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it's an ideal opportunity for the scientists to collect a DNA sample.

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No more than a pin prick to these fat-coated giants.

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Analysis of bowhead tissue samples is revealing

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some extraordinary links between their size and their age.

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Some estimate they are over 200 years old, so this could be a sample of a 200-year-old whale.

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But that would make that animal one of the oldest living animals on the planet.

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Yes, it would be the oldest mammal we know of right now.

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WHALESONG

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Bowheads can live for over 200 years

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because they have a lower body temperature than any other whale,

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and the lower your body temperature, the slower you age.

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These enormous whales can afford to live life slowly,

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roaming the rich Arctic waters,

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simply opening their mouths

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and filtering all the food they need.

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Uniquely, a bowhead's backbone never fuses,

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so all that time they never stop growing.

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Just think of all the wisdom that's in that whale.

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For 200 years he's swum around the Arctic, slowly finding his way around.

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They are amazing, and still mysterious too.

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Although this gentle giant can grow for centuries,

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there is one whale that is even bigger.

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Only in the vastness of the ocean

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could there live the largest creature on earth.

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The blue whale.

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Before commercial whaling,

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300,000 blue whales cruised the oceans.

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Today, less than 10,000 remain.

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We know almost nothing of their lives

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and for years assumed that, like the other great whales,

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they migrated to cold, rich seas to feed.

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Yet, in the warm tropical waters off Sri Lanka in the Indian Ocean,

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blue whales seem to be living here all year round.

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An international team of scientists, led by Anouk Ilangakoon,

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has pioneered blue-whale research here through the decades of civil war.

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This is a once-in-a-lifetime opportunity for cameramen Doug and Didier,

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who have never managed to film blue whales before.

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They're not easy to approach like southern right whales.

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They're not friendly like humpback whales.

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These are very difficult characters.

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If I get one shot of a blue whale underwater,

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that would be a dream come true.

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They head out into blue-whale territory,

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20 miles into the open ocean.

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Despite Anouk's decades studying blue whales,

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she is still unsure how many there are off Sri Lanka,

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and why.

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Sri Lankan blue whales seem to be pretty unique.

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They seem to stay around here year round

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and the real mystery is what are they feeding on?

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And what is there to sustain them throughout the year in these waters?

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Will it finally be possible to record what these mysterious whales are up to?

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The whales remain elusive.

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Did you get me my shot yet?

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That was the first time! No, be patient.

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This is going to be difficult, you know.

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Those whales were... They didn't stop, they just came towards me.

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Perfectly streamlined, blues are one of the fastest ocean giants,

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powering along at over 30 miles an hour.

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But at least they're sticking around.

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So what holds them to this patch of blue sea off Sri Lanka?

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By measuring how temperature and salinity change with depth,

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scientist Asha de Vos believes she has the answer.

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What I've discovered is that along our coastline

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there are these areas of upwelling, pretty large areas,

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which are bringing all this cold, nutrient-rich water

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from the depths to the surface,

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which might be providing conditions for whale food.

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The upwelling of cold, nutrient-rich water is unusual for the tropics,

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but appears to contain the perfect food for blue whales,

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whatever that is.

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Any images of whales feeding in Sri Lanka will not only be a first,

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but will also help support Asha's theory.

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Ironically, the water is so full of nutrients,

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it's too murky to film in.

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I could see that guy almost coming in. He put his head down.

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But, of course, with an 80-foot whale, when the head goes down,

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it's 80 feet down, and I just lost the head.

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Lovely view of the tail going through. Big, big tail.

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I swum very fast toward the whale, but then, all of a sudden,

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I saw all the massive animal coming to me so quickly...

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What an experience.

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I was lucky not to be hit, but I really want to see it again.

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So far, the footage suggests that, if the whales are feeding,

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it must be at depth.

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Ari Friedlaender, another member of the research team,

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is investigating the duration and depth of each whale's dive.

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OK, I think that's the animal from that third group,

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so that dive time is about seven minutes.

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I'd probably say, just based on that dive time, maybe between about 50 and 200 metres.

0:53:020:53:06

I think it's pretty clear that these guys are feeding.

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They're lunging quite a bit down there too.

0:53:090:53:12

Ari is now convinced the whales are feeding at great depth,

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but on what?

0:53:180:53:20

The whales leave behind crucial evidence floating on the surface.

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-This is whale poo.

-Whale poo?!

0:53:300:53:34

That's right. It's red in colour,

0:53:340:53:36

and that gives us a clue to what it is, actually.

0:53:360:53:40

-It's full of krill.

-That's what they feed on?

-That's right.

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The largest creature in the ocean feeds almost exclusively

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on one of the smallest...

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krill.

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A crustacean just a few inches long.

0:53:540:53:57

Krill are normally found in cold polar seas,

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but the unusual conditions off Sri Lanka

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allow krill to thrive in these tropical waters.

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So is that why the blue whales are here?

0:54:140:54:16

We see these animals diving,

0:54:190:54:21

we're counting how long they're down

0:54:210:54:24

and I've got 100% confidence that these guys are diving deep down

0:54:240:54:28

and they're finding these really dense patches of krill and lunge-feeding through them.

0:54:280:54:32

We've made an animation of how these whales feed at depth.

0:54:320:54:36

The blue whale dives to 600 feet,

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below where the krill are hiding in the gloom.

0:54:410:54:44

The whale then powers up through the swarm,

0:54:470:54:50

gulping its own body weight of water into its ballooning throat.

0:54:500:54:55

It then strains out the nutritious krill

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through its fine mesh of baleen.

0:55:010:55:04

Each lunge requires huge effort,

0:55:110:55:14

but if you have a mouth as big as a blue whale's

0:55:140:55:18

you can catch so much food

0:55:180:55:20

that the whole process becomes extraordinarily efficient.

0:55:200:55:24

Their size is the secret of their success.

0:55:280:55:33

Doug and Didier make one final attempt to get up close

0:55:380:55:43

to the deep-feeding giants.

0:55:430:55:45

It was certainly the biggest whale that I've ever seen.

0:56:400:56:42

It just looked enormous underneath me.

0:56:420:56:45

I've waited a long time to see a blue underwater, and that was just magic.

0:56:450:56:50

Beautiful. Fantastic. Today is the best day of my life.

0:56:500:56:55

Pumped up on tonnes of krill,

0:57:000:57:02

blue whales can grow as long as a jetliner,

0:57:020:57:05

weighing almost 200 tonnes,

0:57:050:57:08

twice the size of the largest dinosaur.

0:57:080:57:11

But, worryingly, the blue's giant size

0:57:170:57:20

and its giant appetite are now putting it at risk.

0:57:200:57:24

We know that climate change is occurring,

0:57:240:57:26

and that in places like Antarctica the temperatures have sky-rocketed.

0:57:260:57:31

We also know that krill has started to decrease,

0:57:310:57:33

and when you don't have enough food blue whales are going to have trouble surviving.

0:57:330:57:38

So as climate change happens, as krill starts to be depleted,

0:57:380:57:41

blue-whale survival could be in jeopardy.

0:57:410:57:43

Blue whales are still endangered, but they are recovering, slowly.

0:57:470:57:52

For their recovery to continue, it's not just the whales themselves that will need protection,

0:57:520:57:58

but the seas and the other creatures they depend on.

0:57:580:58:02

We may have missed the chance to live with the great dinosaurs of the past,

0:58:080:58:14

but we do have the good fortune to be sharing our time

0:58:140:58:18

with the largest creatures that ever lived,

0:58:180:58:22

these magnificent ocean giants.

0:58:220:58:25

WHALESONG

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0:58:470:58:51

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