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The open ocean.
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It covers more than half the surface of our planet.
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Yet, for the most part, it's a watery desert,
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empty of life.
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Hunters here spend their lives in a constant search
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for scarce and elusive prey.
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Remarkably, this seemingly barren wilderness
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is home to the largest hunter of them all...
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..the blue whale.
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Weighing 200 tonnes
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and 30 metres long,
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these are the biggest animals ever to have lived.
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Despite their immense size,
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blue whales are one of the most streamlined
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and energy-efficient of all swimmers.
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Their food is so scarce and widely spread
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that blue whales must journey across whole oceans
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just to find a single meal.
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They can travel over 100 miles a day for weeks at a time.
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The ocean's largest animal feeds on one of its smallest.
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Krill - small shrimp-like crustaceans.
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Opening its gigantic mouth takes so much effort
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that they only do so
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when the swarms of krill are rich and concentrated.
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The krill here is too scattered -
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not even worth slowing down for.
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This blue whale's lonely search for food
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must go on.
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Out here, feeding opportunities are always few and far between.
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And they never last long.
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Prey is devoured within minutes.
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When it's all over,
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the hunters must resume their endless search.
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Frigatebirds -
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the pirates of the high seas.
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Soaring effortlessly on the gentle trade winds,
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they can scan vast tracts of ocean for food.
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Frigates must be so lightweight
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that they can't afford the heavy oils
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that waterproof the plumage of other sea birds.
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So getting wet would be lethal.
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This may seem an impossible limitation for a seafaring hunter.
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But frigatebirds overcome this handicap
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with help from others.
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Dorado.
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One of the fastest and most voracious of ocean predators.
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They patrol close to the surface, searching for prey.
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Little fish try to hide amidst the undulating swell of the ocean -
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the only cover there is.
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It's a game of hide and seek
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played out amongst the waves.
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Their cover blown...
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..escape seems impossible.
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But these particular fish have a unique ability.
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They're flying fish.
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With an extra thrust from their tails,
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the flying fish get airborne once more.
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With a good wind,
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they can glide for hundreds of metres.
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But this is just what the frigatebirds
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have been waiting for.
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When frigates join the hunt,
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the flying fish are literally caught between the devil...
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..and the deep blue sea.
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If the flying fish get too much lift
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they become easy prey for the frigates.
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If they dive to evade attack from above...
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..they could fall into the mouths of the dorado.
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With the help of the dorado,
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the wily frigatebird has become a flying fish specialist...
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..and without getting a single feather wet.
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Not all open-ocean hunters are able to travel
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in search of their food.
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Some have no choice but wait for a meal to come to them.
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A mat of sargassum weed drifts in the middle of the Atlantic.
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Sargassum is the only seaweed to live entirely at the surface.
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It never attaches to the sea floor.
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This floating tangle of fronds
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is home to a surprising open-ocean predator -
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the sargassum fish.
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Every part of his body mimics the weed.
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His fins are more suited to walking than swimming.
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In fact, he can barely swim at all.
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He will spend his entire life marooned on this weedy raft.
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This sargassum fish must lie in wait
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for those seeking shelter amongst the weed.
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Unfortunately his mat is empty for now.
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But at least he's not wasting valuable energy
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searching for food.
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In the featureless ocean,
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these mats are much-sought-after sanctuary for juvenile fish.
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At last -
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his first opportunity for weeks.
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He must get closer.
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He can only strike when he's within a few centimetres of his prey.
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Trusting his perfect camouflage,
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he hides in the weed.
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Patience.
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Still not close enough.
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Hunger is clearly getting the better of him.
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Surely this time.
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Blown it.
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It may be weeks before he gets another chance.
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The open ocean is so vast
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that some hunters can only find enough prey
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by searching as a team.
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Dolphins live in highly sophisticated social groups.
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Working together,
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they can cover a huge area of ocean.
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These are spinner dolphins.
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Why they make these twisting leaps is still debatable.
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Perhaps it's a form of communication...
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..or perhaps it's just fun.
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Small groups sometimes come together,
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forming superpods 5,000 strong.
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And these are on the hunt.
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SONAR CLICKS
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Spinners are the most vocal of all the dolphins.
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CLICKING AND CRACKLING
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They use echolocation, a kind of sonar, to find their prey.
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Each hunter sends out a series of clicks
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and then listens for returning echoes...
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..allowing them to scan for distant prey,
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hundreds of metres away.
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CLICKS CONTINUE
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The superpod spreads out into a wide hunting line,
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up to a mile across...
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..producing a wall of sound.
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CONSTANT CLICKING
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They're searching for their favourite prey.
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Lanternfish.
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They are the most numerous fish on the planet.
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But these small fish spend most of their time
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down in the deep ocean, way beyond the reach of dolphins.
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It's only when they come up to the surface to feed
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that they become prey.
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Once they've found a shoal,
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the dolphins use their sonar in a different way.
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SONAR BLASTS
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They stun the fish with loud blasts,
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then simply gather them up.
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As they feed, the dolphins work the underside of the shoal
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to stop their prey from escaping back into the safety of the deep.
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Within a few minutes,
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all that's left is a shower of scales
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drifting downwards to the ocean depths.
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The deep ocean is by far
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the largest habitat for life on Earth...
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..and home to some of the most bizarre hunters of all.
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Down here, food is much scarcer than at the surface,
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so deep-sea predators must do all they can to save precious energy.
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Waiting patiently, a viperfish.
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Special light-producing organs on its head
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entice prey towards fearsome teeth.
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Strange yet deadly jelly hunters also live here.
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Most simply drift,
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trailing tentacles loaded with lethal stings.
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Others, propelled by lines of beating hairs,
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glide gently through the darkness.
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Beroe -
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the top deep-sea jelly predator.
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They actively hunt other jellies...
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..like this ctenophore.
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To grasp its gelatinous prey,
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Beroe has special teeth-like spikes in its mouth.
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Many deep-sea hunters just hang in the abyss,
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saving their energy,
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luring their prey to come to them.
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Chiroteuthis.
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This deep-sea squid fishes for prey using long, sticky tentacles.
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Each has a glowing lure,
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pulsing to attract passing prey.
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A gentle twitch adds to the temptation.
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Down here in the darkness, this meal is a rare bonanza.
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The open ocean may be a vast blue desert,
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but like all deserts, it has oases.
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Scattered widely across this endless space
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are thousands of small islands.
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These are the summits of underwater mountains,
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which rise up from the sea floor many miles below.
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The seamounts deflect deep-ocean currents upwards,
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forcing nutrient-laden water to the surface.
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A busy oasis in the emptiness of the big blue.
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For potential prey, there's plenty of shelter amongst the coral...
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..and in the caves that are hidden beneath the reef itself.
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Small fish take refuge here,
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out of the reach of most of their predators.
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But not all.
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Lionfish.
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They're not built for speed -
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success here depends on delicate manoeuvring.
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Their strategy is to hide in plain sight,
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lulling their prey into a false sense of security.
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The lionfish's stripes are visually confusing,
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making it difficult for their prey to judge how close it is.
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Using its extravagant fins to hide slow and deliberate tail movements,
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it edges ever closer.
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It must get to within a few centimetres,
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close enough for a sudden strike.
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Got one.
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The deep-water currents that sustain so many residents
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also attract visitors to these oases.
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Silky sharks.
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They journey hundreds of miles between seamounts,
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using them as gathering places in the featureless ocean.
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They're joined by hammerheads.
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Both these sharks constantly travel
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between the Galapagos and other isolated seamounts
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in the Eastern Pacific.
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No-one knows for sure why they gather in such numbers,
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but some certainly come to these oases in search of food.
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A school of resident silversides cloaks the seamount.
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If these little fish stay close to the coral,
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the sharks won't be able to get at them.
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Other, more agile visitors are attracted by the potential feast.
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Striped bonito...
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..and golden trevalley.
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To get a meal, they'll need to drive their prey up and away from the reef
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into open water.
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As long as the silversides stick close to the sea floor,
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they should evade their predators.
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This time, the frustrated hunters will have to search elsewhere -
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there's never an easy meal in the open ocean.
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The Southern Ocean encircling Antarctica.
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The wildest seas on our planet.
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Here, it's the storm-tossed waters that bring nutrients to the surface,
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creating isolated patches of richness.
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Far from the calm tropics,
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this weather-beaten ocean is home to the albatross.
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Black-browed albatross are the same size as frigatebirds
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but three times as heavy,
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and so they need a totally different flying technique.
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Albatross have the longest wingspan of any bird,
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and that enables them to exploit the power
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of the Southern Ocean winds.
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First, they glide into the wind,
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harnessing its energy to give them lift.
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Then they turn and descend downwind, picking up speed.
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Soaring on wind fronts like this,
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an albatross can travel
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hundreds of miles of ocean in a day...
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..barely beating its wings.
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They often spend weeks at sea,
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searching for prey without ever returning to land.
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Food at last - a patch of krill close to the surface.
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Because the winds are so strong here,
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albatrosses can afford the extra weight
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of waterproofing oils on their feathers.
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They can duck-dive to no more than a metre,
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so they rely on the churning of the Southern Ocean
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to bring their prey up into range.
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Like all birds, albatross have to breed on land,
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but suitable islands are so few in the South Atlantic
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that most are heavily overcrowded.
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Steeple Jason - one of the largest albatross colonies in the world.
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ALBATROSS SQUAWK
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Nearly half a million come back here each year to raise their young.
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Adults share parenting duties,
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returning every few days to feed their chick.
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Feeding done, it's time to head out to sea.
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They need to make their way to the edge of the packed colony
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where there's more room for takeoff.
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CHICK CRIES
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Albatross are so heavy that they can only get airborne
265
00:32:49,360 --> 00:32:51,760
in places where the wind is strong enough.
266
00:32:55,440 --> 00:32:57,360
Using a special runway...
267
00:33:00,200 --> 00:33:01,720
..with a good headwind...
268
00:33:08,360 --> 00:33:09,400
..she's off.
269
00:33:19,720 --> 00:33:24,040
From the air, the ocean may appear featureless,
270
00:33:24,040 --> 00:33:26,120
but beneath the surface,
271
00:33:26,120 --> 00:33:30,360
a network of powerful currents is constantly on the move.
272
00:33:33,080 --> 00:33:36,240
It's these currents, more than any other force,
273
00:33:36,240 --> 00:33:39,480
that determine the distribution of life out here.
274
00:33:42,360 --> 00:33:44,720
A whole community of ocean drifters
275
00:33:44,720 --> 00:33:47,640
hitches rides on these rivers in the sea.
276
00:33:50,440 --> 00:33:52,560
Pelagic red crabs.
277
00:34:03,320 --> 00:34:06,960
They've gathered to feed on tiny floating plants and animals,
278
00:34:06,960 --> 00:34:09,680
a bloom of plankton fuelled by the currents.
279
00:34:20,920 --> 00:34:24,320
Fine hairs on their legs slow their descent...
280
00:34:26,880 --> 00:34:29,440
..and then, with a few flicks of the tail,
281
00:34:29,440 --> 00:34:32,600
they swim back up to continue feeding.
282
00:34:42,880 --> 00:34:45,680
The currents that carry these wandering crabs
283
00:34:45,680 --> 00:34:49,800
also serve as highways for the ocean's larger predators.
284
00:34:54,920 --> 00:34:56,480
Striped marlin.
285
00:35:01,880 --> 00:35:03,360
Beautifully streamlined,
286
00:35:03,360 --> 00:35:07,000
they can travel huge distances with minimum effort.
287
00:35:09,040 --> 00:35:12,720
These hunters patrol the boundaries between ocean currents,
288
00:35:12,720 --> 00:35:14,720
where their prey often gathers.
289
00:35:18,320 --> 00:35:21,360
Each predator has an incredible sense of smell,
290
00:35:21,360 --> 00:35:24,760
able to detect faint trails left by their prey.
291
00:35:29,840 --> 00:35:33,240
Somewhere out here is the big prize...
292
00:35:35,240 --> 00:35:37,840
..and hunters of all kinds are looking for it.
293
00:35:55,160 --> 00:35:59,560
Great shoals of fish are attracted to a plankton bloom.
294
00:36:01,120 --> 00:36:04,520
A single school of sardines can be many miles long.
295
00:36:10,280 --> 00:36:15,120
The fish swim tightly together - there's safety in numbers.
296
00:36:19,760 --> 00:36:22,560
Their defence relies on coordination.
297
00:36:27,120 --> 00:36:30,320
When attacked, the sardines move as one.
298
00:36:39,720 --> 00:36:43,480
Each fish instantly matches the movements of its neighbour...
299
00:36:45,040 --> 00:36:48,040
..and the whole shoal moves in synchrony.
300
00:36:55,200 --> 00:36:59,000
A lone sea lion can't keep up with their rapid reactions.
301
00:37:08,840 --> 00:37:11,440
Even when more sea lions arrive,
302
00:37:11,440 --> 00:37:15,840
they can't seem to break down the sardines' coordinated defences.
303
00:37:33,760 --> 00:37:37,320
With a shoal this big, the sea lions need to isolate
304
00:37:37,320 --> 00:37:39,760
a smaller, more manageable group of fish.
305
00:37:45,360 --> 00:37:49,760
But with so few predators, the fish still have the advantage.
306
00:37:55,200 --> 00:37:59,680
All the sea lions can do is keep the sardines at the surface
307
00:37:59,680 --> 00:38:01,680
and wait for others to join them.
308
00:38:11,120 --> 00:38:13,720
Tuna.
309
00:38:13,720 --> 00:38:16,680
Their arrival changes everything.
310
00:38:29,280 --> 00:38:31,280
Tuna attack from below,
311
00:38:31,280 --> 00:38:34,800
cutting off the sardines' escape route down to deeper water.
312
00:38:43,680 --> 00:38:47,120
Next to appear, shearwaters -
313
00:38:47,120 --> 00:38:51,440
excellent fliers, but also surprisingly agile underwater.
314
00:38:55,200 --> 00:38:58,440
With so many predators attacking from all sides,
315
00:38:58,440 --> 00:39:02,120
the advantage starts to shift away from the sardines.
316
00:39:22,720 --> 00:39:24,840
As the fish pack ever tighter,
317
00:39:24,840 --> 00:39:28,560
their shoaling strategy now makes it easier for the hunters.
318
00:39:53,600 --> 00:39:55,240
Copper sharks.
319
00:39:55,240 --> 00:39:58,640
They've scented blood in the water.
320
00:40:04,440 --> 00:40:08,480
Surprisingly, perhaps, the predators never attack one another.
321
00:40:08,480 --> 00:40:11,560
They work together to corral the ball of fish,
322
00:40:11,560 --> 00:40:14,320
taking turns to grab a mouthful.
323
00:40:23,840 --> 00:40:25,240
Common dolphins.
324
00:40:28,720 --> 00:40:30,760
As the shoal gets ever smaller,
325
00:40:30,760 --> 00:40:34,720
each sardine scrambles desperately to hide in the middle.
326
00:40:34,720 --> 00:40:37,360
But now, there's no escape.
327
00:40:56,440 --> 00:41:01,240
A Bryde's whale finishes off the feast -
328
00:41:01,240 --> 00:41:05,520
tonnes of sardines devoured in less than an hour.
329
00:41:17,040 --> 00:41:19,960
The predators melt away into the blue...
330
00:41:23,000 --> 00:41:25,960
..going their separate ways once more.
331
00:41:36,320 --> 00:41:39,760
This blue whale is still searching for a meal
332
00:41:39,760 --> 00:41:42,240
to satisfy its giant hunger.
333
00:41:45,080 --> 00:41:46,600
Being so large,
334
00:41:46,600 --> 00:41:50,240
it must catch an average of four tonnes of food a day.
335
00:41:55,760 --> 00:41:59,360
But many days may pass without feeding at all.
336
00:42:04,840 --> 00:42:11,520
It is their great size that enables blue whales to travel the furthest,
337
00:42:11,520 --> 00:42:15,640
roaming every ocean from the tropics to the poles.
338
00:42:15,640 --> 00:42:17,640
BLUE WHALE SPOUTS
339
00:42:29,240 --> 00:42:32,320
Trapped against the surface by fish,
340
00:42:32,320 --> 00:42:34,640
a dense patch of krill.
341
00:42:39,480 --> 00:42:41,200
This blue has finally found
342
00:42:41,200 --> 00:42:44,440
what it's been searching for for so long.
343
00:42:46,480 --> 00:42:51,200
A meal big enough to make opening its massive mouth worthwhile.
344
00:42:56,040 --> 00:42:59,840
The krill swarm is hundreds of metres across
345
00:42:59,840 --> 00:43:01,440
and packed tight.
346
00:43:09,440 --> 00:43:12,360
The whale lines up on its prey,
347
00:43:12,360 --> 00:43:14,880
targeting the densest part of the shoal.
348
00:43:55,280 --> 00:43:59,880
It takes so much effort to swim with a fully extended throat
349
00:43:59,880 --> 00:44:03,240
that the whale virtually comes to a standstill.
350
00:44:16,520 --> 00:44:21,240
The whale uses its tongue to force the water out of its mouth,
351
00:44:21,240 --> 00:44:26,040
trapping the krill on plates of hairy bristles that line its jaw.
352
00:44:30,320 --> 00:44:33,600
But it takes time to sieve so much water.
353
00:44:36,640 --> 00:44:39,440
And that gives more nimble hunters their chance.
354
00:44:54,440 --> 00:44:58,000
Blue whales may not be as agile as other hunters,
355
00:44:58,000 --> 00:45:00,120
but they don't need to be.
356
00:45:02,920 --> 00:45:04,760
In one giant mouthful,
357
00:45:04,760 --> 00:45:07,800
they can swallow whole swarms of krill.
358
00:45:59,160 --> 00:46:02,120
No other predator is better suited
359
00:46:02,120 --> 00:46:07,320
to exploit the scattered riches that the open ocean can provide.
360
00:46:11,320 --> 00:46:14,600
The blue whale -
361
00:46:14,600 --> 00:46:18,640
the greatest hunter in all the world's oceans.
362
00:46:55,880 --> 00:46:59,760
The open ocean created many challenges for the Hunt team.
363
00:47:01,800 --> 00:47:05,680
But none came bigger than trying to film blue whales underwater.
364
00:47:07,840 --> 00:47:11,520
Achieving this was to turn into a two-year mission.
365
00:47:13,800 --> 00:47:16,560
The crew teamed up with John Calambokidis,
366
00:47:16,560 --> 00:47:19,120
the world's foremost blue whale scientist.
367
00:47:21,160 --> 00:47:25,240
John gets crucial information from these harmless tags.
368
00:47:27,720 --> 00:47:32,160
But he can only observe blue whales for the brief time they surface.
369
00:47:34,680 --> 00:47:37,200
Well, part of this research and part of the reason
370
00:47:37,200 --> 00:47:39,880
that, er, we're working with film-makers
371
00:47:39,880 --> 00:47:44,000
is it gives us an unique chance to get scientific information
372
00:47:44,000 --> 00:47:45,720
we wouldn't be able to otherwise.
373
00:47:45,720 --> 00:47:47,680
So we are doing this under our research permit
374
00:47:47,680 --> 00:47:50,640
to get an insight into what they're doing underwater -
375
00:47:50,640 --> 00:47:53,400
how they're diving, how they're swimming, how they're feeding.
376
00:47:56,240 --> 00:47:59,160
Pictures of blue whales are rare.
377
00:47:59,160 --> 00:48:01,800
They're the biggest animal ever to live on the planet,
378
00:48:01,800 --> 00:48:05,280
but there are only a few underwater pictures that exist today.
379
00:48:05,280 --> 00:48:07,200
A few where you can actually see the animal.
380
00:48:07,200 --> 00:48:10,880
First, they have to find a blue whale.
381
00:48:10,880 --> 00:48:13,080
Well, I always feel really embarrassed, you know,
382
00:48:13,080 --> 00:48:16,640
because how can you lose the biggest animal that's ever lived, you know?
383
00:48:16,640 --> 00:48:20,360
But...er, while the whale is big, the ocean is even bigger.
384
00:48:25,120 --> 00:48:26,720
Just over here.
385
00:48:28,160 --> 00:48:32,120
The team's success will depend on good water visibility.
386
00:48:34,680 --> 00:48:38,920
Too murky, and the whale literally disappears into the gloom.
387
00:48:43,640 --> 00:48:44,920
No shot.
388
00:48:46,760 --> 00:48:49,760
The first year was blighted by poor visibility
389
00:48:49,760 --> 00:48:51,680
and the shoot ended in failure.
390
00:48:56,200 --> 00:49:01,000
Year two, and the sea conditions are much better.
391
00:49:04,240 --> 00:49:06,120
Oh, here he is, right here.
392
00:49:06,120 --> 00:49:09,520
Blue whales only surface for two to three minutes at a time
393
00:49:09,520 --> 00:49:13,280
before diving for up to 15 minutes.
394
00:49:13,280 --> 00:49:16,800
It's a narrow window for everything to come together.
395
00:49:16,800 --> 00:49:18,960
There's a bit of tricky manoeuvring here for John.
396
00:49:18,960 --> 00:49:21,080
He's got to try and get the boat
397
00:49:21,080 --> 00:49:23,440
ahead of the whale but not in front of it.
398
00:49:27,560 --> 00:49:29,120
Then David has to swim out
399
00:49:29,120 --> 00:49:32,320
and hope the whale passes close enough to get a shot.
400
00:49:39,280 --> 00:49:41,160
It's too far.
401
00:49:41,160 --> 00:49:44,040
It's a little too far that time.
402
00:49:52,680 --> 00:49:55,440
This year, the water is exceptionally clear...
403
00:49:58,000 --> 00:50:01,440
..but getting David in the right position still takes time.
404
00:50:03,720 --> 00:50:05,560
He went by, I definitely got a shot.
405
00:50:05,560 --> 00:50:06,960
It's not one of our best.
406
00:50:17,160 --> 00:50:18,240
Missed it.
407
00:50:21,400 --> 00:50:22,720
After weeks of effort,
408
00:50:22,720 --> 00:50:24,880
all the elements finally come together,
409
00:50:24,880 --> 00:50:27,840
giving David the chance of a lifetime.
410
00:50:30,680 --> 00:50:34,280
Like, I got down to about 25 feet. I knew that whale was out there.
411
00:50:34,280 --> 00:50:38,560
But, er...he just came out of the blue, right to me.
412
00:50:44,760 --> 00:50:47,720
I could see his eye, the details of his mouth,
413
00:50:47,720 --> 00:50:51,000
every scratch on his skin.
414
00:50:51,000 --> 00:50:53,920
And he cruised on by - it took forever.
415
00:50:53,920 --> 00:50:57,400
You know, they're so big - it just went by like a freight train.
416
00:51:02,080 --> 00:51:04,240
I saw his tail slide by.
417
00:51:04,240 --> 00:51:07,160
And he slipped back into the blue.
418
00:51:07,160 --> 00:51:09,360
It...it was awesome.
419
00:51:09,360 --> 00:51:12,720
That is awesome - I have never, of all my years of doing this,
420
00:51:12,720 --> 00:51:14,120
I've never got a shot like that.
421
00:51:14,120 --> 00:51:15,280
That was amazing.
422
00:51:16,640 --> 00:51:19,640
Images of blue whales underwater are so rare
423
00:51:19,640 --> 00:51:25,360
that this shot of one simply swimming by is a major success.
424
00:51:25,360 --> 00:51:28,160
But the crew need more.
425
00:51:28,160 --> 00:51:30,280
This series is all about hunting,
426
00:51:30,280 --> 00:51:33,920
and so, nice though it is to have that shot, to make a sequence,
427
00:51:33,920 --> 00:51:37,880
we've got to get shots of blue whales eating krill.
428
00:51:37,880 --> 00:51:39,480
And what we've got to wait for
429
00:51:39,480 --> 00:51:41,680
is when the krill actually comes to the surface.
430
00:51:41,680 --> 00:51:44,080
It might happen once, maybe twice a month.
431
00:51:46,560 --> 00:51:49,080
The crew come across an encouraging sign,
432
00:51:49,080 --> 00:51:52,520
from a rather unsavoury source.
433
00:51:52,520 --> 00:51:55,080
That's some whale faeces.
434
00:51:56,680 --> 00:51:59,840
So we've found a big whale poo in the water.
435
00:51:59,840 --> 00:52:03,200
Um, it's a good sign for us, we know that they're feeding here,
436
00:52:03,200 --> 00:52:04,720
so maybe they'll stick around.
437
00:52:07,120 --> 00:52:10,280
Finally, the crew find what they've been looking for -
438
00:52:10,280 --> 00:52:12,120
krill at the surface.
439
00:52:12,120 --> 00:52:13,960
Look at those birds in the water.
440
00:52:13,960 --> 00:52:16,080
So there's a small krill ball.
441
00:52:16,080 --> 00:52:18,040
We're going to go take a look at it.
442
00:52:18,040 --> 00:52:20,400
All right - remember, don't put me right on top of it.
443
00:52:20,400 --> 00:52:22,600
All right, ready? OK, the ball's right here.
444
00:52:22,600 --> 00:52:24,800
- Right here, right here.
- Is it on the surface?
- Yeah.
445
00:52:24,800 --> 00:52:26,280
- Good red?
- Up at the top.
446
00:52:26,280 --> 00:52:28,600
- Got it?
- Yeah, got it.
447
00:52:32,480 --> 00:52:35,560
No-one was prepared for what happened next.
448
00:52:36,760 --> 00:52:40,400
Right behind you! Hey, Hugh, here he comes!
449
00:52:40,400 --> 00:52:41,800
Oh!
450
00:52:43,920 --> 00:52:45,320
Massive surfacing.
451
00:52:46,400 --> 00:52:49,360
Oh, God - that's a shot. I bet you he got it.
452
00:52:50,800 --> 00:52:52,160
I bet you he got it.
453
00:52:52,160 --> 00:52:53,280
Oh!
454
00:52:57,200 --> 00:53:00,320
- MAN ON BOAT:
- God, they're beautiful, aren't they?
455
00:53:00,320 --> 00:53:03,560
- What did you guys get? What did you guys get?
- Oh, my God.
456
00:53:04,800 --> 00:53:06,200
Oh, my God.
457
00:53:07,960 --> 00:53:11,760
I still... I can't actually quite get my head around what I just saw.
458
00:53:11,760 --> 00:53:14,720
We were down there, Dave was filming the krill balls,
459
00:53:14,720 --> 00:53:18,120
and I just noticed, literally between his fins,
460
00:53:18,120 --> 00:53:22,080
this massive great whale just loomed out.
461
00:53:22,080 --> 00:53:24,240
David saw him, panned down.
462
00:53:24,240 --> 00:53:26,760
I don't know where it came from.
463
00:53:29,200 --> 00:53:31,440
Well, when I first looked down and I saw this whale,
464
00:53:31,440 --> 00:53:33,240
I was a little bit stressed out,
465
00:53:33,240 --> 00:53:37,840
because 95 feet of blue whale is going between my fins.
466
00:53:37,840 --> 00:53:42,320
He hooks around, comes up and just grabs a big mouthful.
467
00:53:48,360 --> 00:53:50,360
They're called blue whales for a reason,
468
00:53:50,360 --> 00:53:51,960
you just see them underwater,
469
00:53:51,960 --> 00:53:54,360
this bright, iridescent cobalt blue
470
00:53:54,360 --> 00:53:56,480
just pops out of the blue of the ocean.
471
00:54:00,080 --> 00:54:01,760
Finally, I get round to the other side,
472
00:54:01,760 --> 00:54:04,640
I go "OK, he left," we're like, "Phew! That was pretty intense."
473
00:54:04,640 --> 00:54:06,840
So I'm up trying to get just another shot of the krill
474
00:54:06,840 --> 00:54:09,440
and sure enough, wide open, he comes through one last time.
475
00:54:09,440 --> 00:54:10,960
I was kind of in the wrong spot,
476
00:54:10,960 --> 00:54:13,320
I had to do some serious evasive manoeuvres.
477
00:54:13,320 --> 00:54:15,120
But he comes through, closes his mouth...
478
00:54:15,120 --> 00:54:17,240
It was just amazing.
479
00:54:23,320 --> 00:54:25,600
The whole thing probably lasted ten minutes
480
00:54:25,600 --> 00:54:29,200
but it was hands down, without a doubt, no questions,
481
00:54:29,200 --> 00:54:31,840
the most intense, amazing thing that I've ever seen.
482
00:54:41,840 --> 00:54:45,120
To share the water and to look eye-to-eye with a blue whale
483
00:54:45,120 --> 00:54:47,400
is something I will never, ever forget.
484
00:54:50,560 --> 00:54:53,040
These shots gives John a unique insight
485
00:54:53,040 --> 00:54:55,760
into the feeding behaviour of blue whales.
486
00:54:55,760 --> 00:54:58,200
Let's just look at the side of his mouth there.
487
00:54:58,200 --> 00:55:00,600
So, basically, the water flow, you'd expect,
488
00:55:00,600 --> 00:55:02,560
would be coming out the back there.
489
00:55:02,560 --> 00:55:04,600
Yeah, look at that little fold there,
490
00:55:04,600 --> 00:55:06,240
that is really interesting.
491
00:55:10,320 --> 00:55:12,480
That's a great view.
492
00:55:12,480 --> 00:55:14,520
That's fantastic.
493
00:55:14,520 --> 00:55:18,000
Notice the full rotation there. Oh, that is...
494
00:55:18,000 --> 00:55:20,560
And the full inversion.
495
00:55:20,560 --> 00:55:22,680
OK - that's, again, a unique chance
496
00:55:22,680 --> 00:55:24,760
to see a perspective we don't get to see.
497
00:55:27,040 --> 00:55:29,360
With this close collaboration,
498
00:55:29,360 --> 00:55:33,160
the team have filmed blue whales as never before
499
00:55:33,160 --> 00:55:35,640
and at last have started to reveal
500
00:55:35,640 --> 00:55:38,920
the secret life of the ocean's greatest hunter.
501
00:55:45,760 --> 00:55:48,640
Next time, the hunt is on out in the open.
502
00:55:50,720 --> 00:55:52,560
On the deserts and grasslands...
503
00:55:59,840 --> 00:56:03,440
..where hunters and hunted have nowhere to hide.
504
00:56:08,960 --> 00:56:12,760
For a free interactive Open University poster, call...
505
00:56:16,960 --> 00:56:18,240
..or go to...
506
00:56:21,120 --> 00:56:23,680
..and follow the links to the Open University.
38060
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