0:00:08 > 0:00:11It's the end of a long arctic winter.
0:00:15 > 0:00:20A mother polar bear emerges from her den deep beneath the snow.
0:00:23 > 0:00:26She's endured months of freezing temperatures to give birth
0:00:26 > 0:00:28to her cubs.
0:00:36 > 0:00:39Ahead of them is the adventure of a lifetime.
0:00:43 > 0:00:47To survive, the polar bear cubs must follow their mother
0:00:47 > 0:00:49on an incredible 400 mile trek
0:00:49 > 0:00:53to the edge of the North Pole's pack ice.
0:00:53 > 0:00:58It's the greatest challenge of their young lives.
0:00:58 > 0:01:01They'll encounter strange creatures...
0:01:04 > 0:01:06..brave treacherous ice...
0:01:08 > 0:01:09..perilous seas...
0:01:11 > 0:01:12..and threatening males.
0:01:15 > 0:01:17It's a journey full of surprises...
0:01:20 > 0:01:23..as they learn to thrive in a frozen world.
0:01:26 > 0:01:29This is a dramatized story based on the extraordinary
0:01:29 > 0:01:32adventures of nature's Snow Bears.
0:01:41 > 0:01:44High on the southern slopes of the mountains,
0:01:44 > 0:01:48deep snowdrifts kept their den safe from winter storms.
0:01:50 > 0:01:54The downside of their location is, well, getting down.
0:01:57 > 0:01:59One cub seems fearless...
0:02:07 > 0:02:10..his sister is a little less confident.
0:02:14 > 0:02:19But to get down safely this cub must trust her mother.
0:02:23 > 0:02:25Her reassurance goes a long way.
0:02:25 > 0:02:27CUB CALLS
0:02:36 > 0:02:39There are no nursery slopes when you are 1,000 feet up.
0:02:45 > 0:02:50And with every step the slope becomes increasingly treacherous.
0:02:53 > 0:02:57Tiny paws are no match for powdery snow.
0:03:13 > 0:03:15The nervous cubs need some tough love.
0:03:30 > 0:03:35However there is an easier way down...
0:03:40 > 0:03:44..if they can just get the hang of it.
0:03:48 > 0:03:53After seven months in the den, the soft fresh snow must be bliss.
0:03:53 > 0:03:56MOTHER GRUNTS
0:03:56 > 0:04:00As the cubs' confidence increases, so does the fun.
0:04:28 > 0:04:32Halfway down, and the cubs are ready for a break.
0:04:45 > 0:04:49Their mother's milk is almost a third fat -
0:04:49 > 0:04:52high-energy fuel for their adventure ahead.
0:05:01 > 0:05:04After months of winter darkness,
0:05:04 > 0:05:07the sun's return to Svalbard marks a turning point.
0:05:11 > 0:05:15For the bears, it means leaving their island.
0:05:23 > 0:05:26When the ice melts in spring, the seals vanish with it,
0:05:26 > 0:05:29so they must follow their prey north.
0:05:33 > 0:05:38The first leg will be to walk 250 miles on the frozen sea
0:05:38 > 0:05:39that hugs the coastline.
0:05:44 > 0:05:47They'll pass the great glacial fjords,
0:05:47 > 0:05:50before reaching the northern tip of the island.
0:05:56 > 0:06:00Here they'll venture onto the floating sea ice to cover
0:06:00 > 0:06:02the final 150 miles.
0:06:10 > 0:06:13Their destination - the seal-rich edge of the pack ice
0:06:13 > 0:06:15surrounding the North Pole.
0:06:28 > 0:06:31But if they don't leave the island in time, the sea ice will be gone
0:06:31 > 0:06:34and they could be marooned here for the summer.
0:06:37 > 0:06:42With little to eat, the cubs would be unlikely to survive.
0:06:46 > 0:06:50For mothers with cubs it's not just the melting ice that's a threat.
0:06:52 > 0:06:54A large male.
0:07:05 > 0:07:08He's searching for a mate
0:07:08 > 0:07:12and they sometimes kill cubs so they can have a family of their own.
0:07:27 > 0:07:30The cubs sense the danger.
0:07:38 > 0:07:39Their mother blocks his path...
0:07:43 > 0:07:46..but the male sees this as an invitation.
0:07:46 > 0:07:49CUBS CALL
0:07:52 > 0:07:54MALE GROWLS
0:07:54 > 0:07:59But she has a plan - lead him as far from her cubs as possible.
0:08:10 > 0:08:13On the slopes she's faster and more agile.
0:08:18 > 0:08:20She's soon giving him the run-around.
0:08:28 > 0:08:31CUBS CALL
0:08:36 > 0:08:39MALE GROWLS
0:08:46 > 0:08:50Courting males will stalk females for many weeks.
0:08:52 > 0:08:55CUBS CALL
0:09:00 > 0:09:02He shadows her closely.
0:09:04 > 0:09:07Somehow she must give him the slip.
0:09:09 > 0:09:12CUB CALLS
0:09:27 > 0:09:30But he's not the only one looking for a mate.
0:09:38 > 0:09:42Rivalry is always fierce among the males.
0:09:42 > 0:09:46He won't give her up without a fight.
0:09:49 > 0:09:52THEY GROWL
0:09:54 > 0:09:56She takes her chance to sneak away.
0:10:02 > 0:10:05Bears sometimes fight to the death over females.
0:10:20 > 0:10:23Now to make good their escape.
0:10:29 > 0:10:32But a quick getaway isn't easy.
0:10:42 > 0:10:44One cub realises the urgency...
0:10:49 > 0:10:50..but the other is struggling.
0:10:54 > 0:10:57Luckily, there is an easier way.
0:11:15 > 0:11:18Finally the rival is driven off.
0:11:24 > 0:11:30The amorous male may have won the fight, but he's lost his prize.
0:11:39 > 0:11:42The family can't afford any more hold-ups.
0:11:51 > 0:11:56For the cubs, the journey north is full of new experiences.
0:11:58 > 0:12:01Svalbard reindeer are the world's smallest, but that doesn't
0:12:01 > 0:12:03make them easy to catch
0:12:03 > 0:12:06so they're not on this mother's menu.
0:12:10 > 0:12:13These little reindeer survived the winter by eating lichens
0:12:13 > 0:12:16buried under the snow.
0:12:21 > 0:12:25But there's no time to stop and stare - they're on a tight schedule.
0:12:32 > 0:12:35Heading north, they hug the frozen coastline for speed.
0:12:52 > 0:12:55Adult bears can travel 50 miles a day,
0:12:55 > 0:12:59but for the cubs even ten miles is a struggle.
0:13:01 > 0:13:04They are tired and can walk no more.
0:13:13 > 0:13:17At three months old they need six rest-breaks a day.
0:13:40 > 0:13:42The male has picked up their scent.
0:13:49 > 0:13:53Polar bears will pursue females over vast distances.
0:14:01 > 0:14:05And here, there's no covering your tracks.
0:14:10 > 0:14:12They must get moving,
0:14:12 > 0:14:15but their mother hasn't eaten for seven months
0:14:15 > 0:14:17and is weak with hunger.
0:14:24 > 0:14:25A ringed seal...
0:14:27 > 0:14:31..a chance for the cubs to have a hunting lesson.
0:14:45 > 0:14:51Stealth and complete silence are essential.
0:14:55 > 0:14:59The cubs are trying their best to stay interested.
0:15:09 > 0:15:10It doesn't last.
0:15:27 > 0:15:30Time for a bit of discipline -
0:15:30 > 0:15:32polar bear style.
0:15:57 > 0:15:59CUB CALLS
0:16:01 > 0:16:04Luckily, the sea ice is rich in seals.
0:16:10 > 0:16:12A naive young pup.
0:16:12 > 0:16:14He's unlikely to have ever seen a bear.
0:16:34 > 0:16:36She treads gently,
0:16:36 > 0:16:40not easy when you weigh almost a quarter of a ton.
0:16:41 > 0:16:44The ice soon gives her away.
0:16:46 > 0:16:48The mother seal tries to warn her pup.
0:16:50 > 0:16:53The mother bear has other ideas.
0:16:58 > 0:17:01The pup remains blissfully unaware.
0:17:03 > 0:17:05A last desperate warning.
0:17:08 > 0:17:09Message received.
0:17:21 > 0:17:23A set back -
0:17:23 > 0:17:25but she can't afford to give up.
0:17:35 > 0:17:39Every 30 minutes, the seals must take a breath
0:17:39 > 0:17:41and she'll be waiting.
0:17:41 > 0:17:44This lesson is all about patience.
0:17:46 > 0:17:50The female cub seems to be taking the lesson seriously.
0:17:50 > 0:17:52One day she'll have her own young to feed.
0:17:54 > 0:17:58Her brother prefers making snowballs.
0:18:15 > 0:18:18At last, the waiting is over...
0:18:23 > 0:18:24..but it's the wrong hole.
0:18:27 > 0:18:29Even the experts can get it wrong.
0:18:33 > 0:18:36Still hungry, they must keep hunting.
0:18:44 > 0:18:46The bears aren't the only carnivores
0:18:46 > 0:18:49trying to scratch a living on the island.
0:18:54 > 0:18:57Arctic foxes get through the winter scavenging for scraps
0:18:57 > 0:18:59and surviving on their food stores.
0:19:03 > 0:19:07The warmer spring air means the good times are on their way.
0:19:12 > 0:19:16Unlike the bears, they can't wait for the ice to melt.
0:19:16 > 0:19:19The summer will bring out the nesting birds they prey on.
0:19:25 > 0:19:30For the cubs, a break from walking is always welcome.
0:19:36 > 0:19:39FOXES SQUEAL
0:19:50 > 0:19:53But their mother senses a different opportunity.
0:19:58 > 0:20:01One of the foxes is digging up his winter food stores.
0:20:01 > 0:20:05Leftovers are his insurance policy against starvation.
0:20:10 > 0:20:13But his secret is out.
0:20:18 > 0:20:20In times of need,
0:20:20 > 0:20:22polar bears aren't beneath stealing.
0:20:30 > 0:20:35It's a welcome snack for the mother and the cubs' first taste of meat.
0:20:38 > 0:20:41Foxes scavenge from polar bears,
0:20:41 > 0:20:44perhaps it's only fair that they return the favour.
0:20:47 > 0:20:50FOX CALLS
0:20:50 > 0:20:53The Arctic fox spots another intruder.
0:20:57 > 0:20:59The amorous male is back.
0:21:04 > 0:21:05She must think quickly.
0:21:08 > 0:21:11She can't outrun him on the flat coastal ice.
0:21:14 > 0:21:17She must lead the cubs up and over the mountains.
0:21:22 > 0:21:24On the steep slopes
0:21:24 > 0:21:28the massive male will struggle to keep up with the more nimble family.
0:21:32 > 0:21:36At twice the weight of the female, it's heavy going.
0:21:57 > 0:22:01But with his prize in sight he is not giving up.
0:22:06 > 0:22:08Nearing the summit,
0:22:08 > 0:22:09the family have become trapped.
0:22:11 > 0:22:13The male sees his chance.
0:22:18 > 0:22:20The cubs are panicking.
0:22:21 > 0:22:24CUB CALLS
0:22:28 > 0:22:32To escape, they must somehow scale the wall of ice and snow.
0:22:45 > 0:22:48But he's matching them step for step.
0:22:51 > 0:22:53The stronger male cub is keeping up.
0:22:54 > 0:22:57His sister struggles.
0:23:05 > 0:23:07Their mother has paved the way,
0:23:07 > 0:23:10now it's all down to her cubs.
0:23:52 > 0:23:56With one last effort, the little one is up.
0:24:02 > 0:24:05But the male is grappling with the steepest part.
0:24:07 > 0:24:10Now SHE has the advantage.
0:24:11 > 0:24:14Time to strike.
0:24:28 > 0:24:30For the male,
0:24:30 > 0:24:33there's no dignified way to do this.
0:24:52 > 0:24:54HE GRUNTS
0:24:57 > 0:25:00The family are safe,
0:25:00 > 0:25:04but climbing over the mountain has cost them precious time and energy.
0:25:10 > 0:25:14The mother can see that the ice is starting to melt,
0:25:14 > 0:25:16and there's still a long way to the end of the island.
0:25:22 > 0:25:24Best to take the quickest way down.
0:25:49 > 0:25:53Looking for a meal, the family head for the sea ice.
0:25:58 > 0:26:00But the conditions are different here.
0:26:05 > 0:26:09The seals can be found hiding out in chambers under the snowdrifts.
0:26:14 > 0:26:17But it's no problem - she can still smell a seal under
0:26:17 > 0:26:19a metre of snow.
0:26:26 > 0:26:29Even the Arctic fox can see she's onto something.
0:26:32 > 0:26:36Once located, it's a case of smash and grab.
0:26:41 > 0:26:44And for the cubs, it's watch and learn.
0:26:49 > 0:26:52Getting it right demands precision and experience.
0:27:08 > 0:27:11This is it - the big one.
0:27:14 > 0:27:15Or maybe not.
0:27:29 > 0:27:31But there's no shame in failure -
0:27:31 > 0:27:34only one in ten hunts succeed.
0:27:43 > 0:27:45Triumph at last.
0:27:49 > 0:27:52These cubs are about to get their first taste of fresh seal.
0:27:59 > 0:28:02It's her first proper meal for seven months
0:28:02 > 0:28:06and it couldn't have come at a better time.
0:28:06 > 0:28:09The tip of the island is still two weeks' walk away.
0:28:13 > 0:28:16MOTHER GROWLS, FOX CALLS
0:28:17 > 0:28:20The fox will have to wait his turn.
0:28:23 > 0:28:25CUB GROWLS
0:28:32 > 0:28:36With full bellies, the family make good progress.
0:28:37 > 0:28:41But as the days warm, the cycle of melt and freeze
0:28:41 > 0:28:44has turned the frozen sea into an ice rink.
0:28:53 > 0:28:58Adult bears have rough, furry footpads that give a nonslip grip.
0:28:58 > 0:29:01Cubs are not so well-equipped.
0:29:09 > 0:29:13But on thin ice it's their mother who's in difficulty.
0:29:16 > 0:29:18She tries to spread her weight...
0:29:21 > 0:29:24..but ultimately something has to give.
0:30:16 > 0:30:19The summer melt has arrived early.
0:30:25 > 0:30:30And the state of the ice is a sign that time is running out.
0:30:41 > 0:30:44With the sea ice vanishing, the polar bear family's chances
0:30:44 > 0:30:47of getting safely off the land fade too.
0:30:50 > 0:30:54But they have no choice - they must keep going.
0:30:59 > 0:31:01Shattered by the pace of the journey,
0:31:01 > 0:31:04the cubs need some time to recover.
0:31:25 > 0:31:29Ahead is one of the most dangerous parts of the journey -
0:31:29 > 0:31:31the glacial fjords.
0:31:49 > 0:31:51It's a treacherous place in spring,
0:31:51 > 0:31:54as active glaciers become increasingly unstable.
0:31:59 > 0:32:02The mother looks for a safe route across,
0:32:02 > 0:32:04while the cubs stay back.
0:32:06 > 0:32:07But something's wrong.
0:32:09 > 0:32:12RUMBLING
0:32:41 > 0:32:45Thousands of tonnes of carving glacier
0:32:45 > 0:32:48create a wall of water, pulverizing the sea ice.
0:33:17 > 0:33:18Somehow she survived...
0:33:20 > 0:33:23..but in the chaos she's lost her cubs.
0:34:08 > 0:34:10She's picked up a scent.
0:34:27 > 0:34:30And on an iceberg, signs of life.
0:34:32 > 0:34:33Her cubs.
0:35:11 > 0:35:14Undeterred, the family move on -
0:35:14 > 0:35:16they need to get out of here.
0:35:26 > 0:35:29With the glacial fjords behind them, they are nearing the tip
0:35:29 > 0:35:30of the island.
0:35:42 > 0:35:47They've made it, but exposed rocks are not a good sign.
0:35:54 > 0:35:59The ice flows, which provide safe onward passage for polar bears,
0:35:59 > 0:36:00have melted away.
0:36:09 > 0:36:11The mother faces a dilemma -
0:36:11 > 0:36:15drowning is the greatest risk her cubs face -
0:36:15 > 0:36:19so do they swim, in the hope of reaching drifting ice,
0:36:19 > 0:36:22or stay put and face starvation?
0:36:30 > 0:36:35The arrival of the amorous male makes her decision easy.
0:36:36 > 0:36:38She takes her chance,
0:36:38 > 0:36:41hoping the cubs can make it to the nearest ice floes.
0:36:50 > 0:36:52The crossing is a test of strength and character.
0:36:59 > 0:37:03Adult bears can easily swim 60 miles nonstop,
0:37:03 > 0:37:05but not the youngsters.
0:37:08 > 0:37:12Swimming in their mother's wake means less resistance.
0:37:12 > 0:37:14They save valuable energy.
0:37:21 > 0:37:23But eventually the cubs have to rest.
0:37:25 > 0:37:28Fortunately, salvation is on the horizon.
0:37:33 > 0:37:37A small iceberg, cast adrift from the glacier.
0:37:47 > 0:37:50But other bears have beaten them to it.
0:38:11 > 0:38:15The ice is a good sign though - there will be more.
0:38:22 > 0:38:25At last, an ice floe.
0:38:25 > 0:38:26The gamble was worth it.
0:38:49 > 0:38:51Time to dry off -
0:38:51 > 0:38:53the polar bear way.
0:39:38 > 0:39:42But it sounds like the family aren't alone here after all.
0:39:42 > 0:39:44WATER SPLASHING
0:39:49 > 0:39:52Perhaps it's a chance for a meal.
0:39:52 > 0:39:55Instead the cubs get their first glimpse of one of
0:39:55 > 0:39:58the Arctic's strangest creatures -
0:39:58 > 0:39:59the narwhal.
0:40:17 > 0:40:20These whales, with their strange tusk
0:40:20 > 0:40:24shaped like a mythical unicorn's horn, are a good sign.
0:40:30 > 0:40:34They are also heading for the fertile waters of the far north.
0:40:41 > 0:40:44Narwhals gather where there's food in abundance.
0:40:47 > 0:40:49And where there's fish, there's seals.
0:40:57 > 0:40:58On the ice floes,
0:40:58 > 0:41:02polar bears have to use a completely different hunting technique.
0:41:04 > 0:41:07She must ambush them from the water.
0:41:16 > 0:41:20Stealth is essential.
0:41:31 > 0:41:35Pinpointing the seal requires deadly accuracy.
0:41:42 > 0:41:44For most of the hunt,
0:41:44 > 0:41:46her quarry will be out of sight.
0:41:54 > 0:41:57She must close the distance without being spotted.
0:42:04 > 0:42:07Submerging makes her invisible -
0:42:07 > 0:42:11she can calculate the exact spot where the seal can be found.
0:42:20 > 0:42:23The seal doesn't suspect a thing...
0:42:24 > 0:42:26..except for one small problem...
0:42:28 > 0:42:31..or rather two.
0:42:43 > 0:42:46The mother wonders where it all went wrong...
0:42:48 > 0:42:50..while the cubs reflect on what they've done.
0:43:04 > 0:43:07As the summer takes hold, temperatures rise
0:43:07 > 0:43:10and the melting drift ice breaks apart.
0:43:18 > 0:43:20With the passing weeks,
0:43:20 > 0:43:23the distances between rest stops are increasing...
0:43:25 > 0:43:28..but the growing cubs are rising to the challenge.
0:43:34 > 0:43:37Their mother has picked up a scent.
0:44:03 > 0:44:06It's now a case of following her nose.
0:44:18 > 0:44:22The scent trail is coming from the carcass of a fin whale.
0:44:24 > 0:44:28Its natural death offers both food and rest for the family.
0:44:45 > 0:44:49Energy-rich blubber will supercharge the cubs.
0:44:59 > 0:45:03But this family are not the only bears heading north.
0:45:09 > 0:45:13The male that was shadowing them has also picked up the scent.
0:45:19 > 0:45:21He can swim twice as fast as the family
0:45:21 > 0:45:23and is making good progress.
0:45:32 > 0:45:35The mother knows the whale is a magnet
0:45:35 > 0:45:37for other bears, so they must eat quickly.
0:45:42 > 0:45:46He's found it...and the family too.
0:46:01 > 0:46:04He may just be hungry...
0:46:04 > 0:46:06but they can't take the risk.
0:46:20 > 0:46:23The family continue their marathon swim.
0:46:27 > 0:46:30Then something strange floats into view.
0:46:33 > 0:46:36Irresistible to a curious cub.
0:46:42 > 0:46:44It's a sleeping walrus...
0:46:44 > 0:46:47WALRUS SNORES
0:46:47 > 0:46:50..enjoying a little peace and quiet.
0:46:57 > 0:46:59He's making the oddest noises.
0:46:59 > 0:47:02WALRUS TRUMPETS
0:47:15 > 0:47:18The rest of the herd are awake and alert.
0:47:20 > 0:47:23Their calves are occasionally taken by polar bears.
0:47:30 > 0:47:33But in the water the walruses feel safe.
0:47:33 > 0:47:36They even come to investigate the cubs.
0:48:03 > 0:48:07Walruses favour the rich waters of the far north -
0:48:07 > 0:48:09the bears must be close to their goal.
0:48:19 > 0:48:24One of the cubs is tired and tries to hitch a ride,
0:48:24 > 0:48:26but he's far too big for that.
0:48:33 > 0:48:36The ice floes are getting denser.
0:48:36 > 0:48:37Hunting should be good here.
0:48:52 > 0:48:53A snoozing seal.
0:48:55 > 0:48:57And a look that says,
0:48:57 > 0:49:00"Stay put and stay quiet."
0:49:17 > 0:49:21Bearded seals weigh around a quarter of a ton.
0:49:21 > 0:49:23If the mother can catch it,
0:49:23 > 0:49:27this family will have enough energy to fuel their onward journey.
0:49:58 > 0:50:02She's as silent as the drifting ice.
0:50:51 > 0:50:54Her success feels like a turning point...
0:51:01 > 0:51:03..and a taste of things to come.
0:51:08 > 0:51:12But a white rainbow warns of a change in the weather.
0:51:34 > 0:51:38Their destination is so close now,
0:51:38 > 0:51:39but they can't continue.
0:51:57 > 0:51:59They just have to sit it out.
0:52:25 > 0:52:27As the skies clear,
0:52:27 > 0:52:31it seems the storm has pushed their ice floe closer to the pack ice.
0:52:34 > 0:52:38In between, dozens of seals play in the narrow channel.
0:52:44 > 0:52:45It's this reliable food supply
0:52:45 > 0:52:49which makes the edge of the pack ice a polar bear paradise.
0:52:54 > 0:52:58One last swim and they'll be home and dry.
0:53:03 > 0:53:07But a seal so close is irresistible.
0:53:07 > 0:53:09SEAL SNORTS
0:53:16 > 0:53:19Seals are superior swimmers
0:53:19 > 0:53:22and delight in taunting young bears.
0:53:38 > 0:53:41But the big male has also arrived.
0:53:41 > 0:53:45He's been on the same journey for 400 miles.
0:53:48 > 0:53:51The young cub realises he's in trouble.
0:54:10 > 0:54:13It's rare for a male to find a cub alone.
0:54:15 > 0:54:18Without his mother, he's defenceless.
0:54:39 > 0:54:40She checks on her cubs...
0:54:44 > 0:54:46..and realises one's missing.
0:54:56 > 0:54:59She can't make out what's happening.
0:55:07 > 0:55:10But what seems at first to be aggression
0:55:10 > 0:55:12may just be curiosity.
0:55:20 > 0:55:23Then, as quickly as it started,
0:55:23 > 0:55:25the encounter is over.
0:55:34 > 0:55:37The cub is shaken but unscathed.
0:55:42 > 0:55:43Through the journey
0:55:43 > 0:55:46the male's focus has shifted.
0:55:51 > 0:55:53Now he's reached the pack ice,
0:55:53 > 0:55:57his thoughts have turned to his stomach rather than the female.
0:56:03 > 0:56:05They've made it.
0:56:05 > 0:56:08The family can relax at last.
0:56:11 > 0:56:13There may be bears everywhere
0:56:13 > 0:56:15but there's nothing to fear.
0:56:22 > 0:56:24Everyone has a full belly...
0:56:29 > 0:56:33..and with food in abundance, no reason to fight or flee.
0:56:42 > 0:56:46The family will spend the rest of the summer gorging on seals,
0:56:46 > 0:56:48fattening up for the return trip
0:56:48 > 0:56:52and for the cycle to start all over again.
0:56:54 > 0:56:56Every year across the Arctic,
0:56:56 > 0:56:58polar bears make extraordinary journeys
0:56:58 > 0:57:01in their constant quest for food.
0:57:03 > 0:57:07So life will be one endless adventure
0:57:07 > 0:57:08for the Snow Bears.