0:00:08 > 0:00:11It's a universal dream to fly like a bird.
0:00:11 > 0:00:14To soar on wings into the heavens.
0:00:16 > 0:00:20But it's nothing compared to the reality.
0:00:21 > 0:00:25This is our planet seen as never before.
0:00:28 > 0:00:30A bird's eye view.
0:00:33 > 0:00:36Theirs is a journey that covers the world...
0:00:39 > 0:00:42..filled with astonishing natural events...
0:00:43 > 0:00:46..extreme challenges...
0:00:48 > 0:00:50..and hard-won rewards.
0:00:51 > 0:00:54This is the world on the wing.
0:01:18 > 0:01:23It's spring, and tens of thousands of white storks have left Africa
0:01:23 > 0:01:27and are trying to reach their breeding grounds a thousand miles away in Europe.
0:01:31 > 0:01:34They, like countless millions of other birds,
0:01:34 > 0:01:37face many challenges on the journey ahead.
0:01:39 > 0:01:42Already, these storks might not make it.
0:01:42 > 0:01:47They have been blown off course and out into the Sea of Marmara.
0:01:47 > 0:01:50The storks need rising currents of hot air to soar
0:01:50 > 0:01:54but these thermals can't form over water.
0:01:57 > 0:02:01The sheer effort of flapping their wings is taking its toll.
0:02:06 > 0:02:10And the storks are dropping dangerously low.
0:02:23 > 0:02:28If a wing as much as touches the water, they will fall in and drown.
0:02:28 > 0:02:30They are battling for their lives.
0:02:39 > 0:02:42But they have a lifeline.
0:02:44 > 0:02:49An outcrop rising from the sea, the Princes' Islands.
0:02:51 > 0:02:55Just enough sun-baked rock to create thermals.
0:03:03 > 0:03:06They must quickly gain as much height as they can.
0:03:25 > 0:03:29In this way, they can use the islands as stepping stones across the sea.
0:03:50 > 0:03:53Mainland Europe is tantalisingly close.
0:04:00 > 0:04:02They soar upwards one last time.
0:04:07 > 0:04:09Then glide the seven miles towards it.
0:04:34 > 0:04:40Istanbul - the gateway to Europe for millions of migrating birds arriving from Africa.
0:04:52 > 0:04:57They spiral over the city before setting off to re-colonise the continent.
0:05:04 > 0:05:09These storks are among the countless millions of birds
0:05:09 > 0:05:11that risk their lives to come to Europe to breed.
0:05:22 > 0:05:26Many try to choose a less hazardous route into the continent.
0:05:30 > 0:05:35Grey cranes cross the Mediterranean at the Straits of Gibraltar.
0:05:37 > 0:05:42Here, just 13 miles of sea separate Africa from Europe.
0:05:47 > 0:05:50Ahead is the famous Rock of Gibraltar.
0:06:07 > 0:06:10Reaching land is just stage one of their goal
0:06:10 > 0:06:14as they have an appointment to keep in the far north of the continent.
0:06:16 > 0:06:18The cranes don't pass unnoticed.
0:06:20 > 0:06:24Barbary macaques were introduced from Africa hundreds of years ago.
0:06:24 > 0:06:29Each spring, they witness this mass migration from their original home just across the sea.
0:06:45 > 0:06:50Swallows flew the length of Africa to reach here.
0:06:50 > 0:06:52Many will travel another thousand miles or more
0:06:52 > 0:06:55before they reach their nest sites.
0:07:10 > 0:07:13On a good day, cranes can travel 500 miles.
0:07:17 > 0:07:21But three days of flying leaves cranes tired and hungry.
0:07:25 > 0:07:31The Camargue, Europe's largest river delta, is the perfect place for a spot of R&R.
0:07:57 > 0:08:00Below are the Camargue's famous white horses,
0:08:00 > 0:08:04a breed that has roamed the marshes for centuries.
0:08:31 > 0:08:36Crane families find the best feeding spots by joining other travel-weary birds.
0:08:50 > 0:08:56Here, they will take on board the provisions they need for the journey ahead.
0:09:08 > 0:09:13They are joined by greater flamingos, fresh from West Africa.
0:09:20 > 0:09:2412,000 breeding pairs spend the summer here.
0:09:24 > 0:09:28The salty lagoons provide everything they could wish for.
0:09:36 > 0:09:40But life here isn't quite as peaceful as they'd hoped.
0:09:50 > 0:09:56The flamingos arrive in the breeding season, as feisty stallions try to round up the mares.
0:10:46 > 0:10:47Time to find a quieter lagoon.
0:10:48 > 0:10:52Fortunately the Camargue has hundreds to choose from.
0:11:14 > 0:11:19The cranes can't rest for long, they are bound for Scandinavia
0:11:19 > 0:11:23where they have a date to keep with thousands of other birds.
0:11:33 > 0:11:36The storks are equally pushed for time.
0:11:36 > 0:11:38The first to appear in Europe are males,
0:11:38 > 0:11:42racing to reach their nest sites before the females arrive.
0:11:46 > 0:11:49Cities are an essential part of their flight plan.
0:11:58 > 0:12:02Hard reflective surfaces are better at creating thermals than the surrounding countryside.
0:12:18 > 0:12:21Roofs act like storage heaters,
0:12:21 > 0:12:24pumping out heat even when the sun's behind a cloud.
0:12:35 > 0:12:40Sun-baked roads form a matching highway of hot air in the sky above.
0:12:40 > 0:12:44In fact, our urban sprawl now helps the storks migrate.
0:12:50 > 0:12:54A warm city benefits birds in other ways, too.
0:12:59 > 0:13:02Each winter evening, attracted by the heat of the city,
0:13:02 > 0:13:05five million starlings stream into Rome.
0:13:16 > 0:13:18Before they roost,
0:13:18 > 0:13:22their manoeuvres create nature's greatest aerial display.
0:13:27 > 0:13:30Their iridescent plumage is lit up by the setting sun.
0:13:43 > 0:13:46But this spectacular performance isn't for fun.
0:13:48 > 0:13:52The peregrine falcon is looking for his evening meal
0:13:52 > 0:13:56and he's hunting the world's best formation flying team.
0:14:24 > 0:14:27Their mesmeric waves confuse the peregrine.
0:14:27 > 0:14:29He can't lock onto a single target.
0:14:45 > 0:14:46To achieve such synchrony,
0:14:46 > 0:14:50each starling shadows seven of his nearest neighbours.
0:14:52 > 0:14:55They react 10 times faster than any human pilot.
0:15:03 > 0:15:06To stand a chance, the peregrine must up his game.
0:15:32 > 0:15:37Despite his best efforts, the peregrine has been outmanoeuvred and outperformed.
0:15:47 > 0:15:50For the starlings, city life is just for the winter.
0:15:50 > 0:15:54They will soon head for the wilds of Siberia to breed.
0:16:03 > 0:16:06Cities aren't always so popular with birds.
0:16:08 > 0:16:13Venice was once an area of marshland where migrating cranes could rest and feed.
0:16:14 > 0:16:17Now they have to keep on flying.
0:16:34 > 0:16:36A mother can help her tired offspring.
0:16:36 > 0:16:41Air rising from her wingtips gives a boost to those following in her wake.
0:17:09 > 0:17:12As they follow, young birds also learn the route.
0:17:12 > 0:17:16Next year they will have to make the journey on their own.
0:17:44 > 0:17:47Further along the coast, some marshlands still remain -
0:17:47 > 0:17:50a perfect place to stop and recuperate.
0:18:01 > 0:18:04Despite Europe's dwindling wild places,
0:18:04 > 0:18:08it's still a magnet for breeding birds.
0:18:13 > 0:18:16Sand martins fly from South Africa
0:18:16 > 0:18:19just to nest in the banks of this river in Hungary.
0:18:21 > 0:18:24They are here for the abundant insect life,
0:18:24 > 0:18:28but, as their chicks grow, demand outstrips supply.
0:18:34 > 0:18:38But in their time of need, the river provides a perfect banquet.
0:18:45 > 0:18:47One by one, they emerge.
0:19:00 > 0:19:02They are mayflies.
0:19:05 > 0:19:09Their moment of glory lasts just three hours.
0:19:09 > 0:19:11Just time enough to mate and lay eggs.
0:19:21 > 0:19:25They are a "superfood" for the hungry chicks.
0:20:21 > 0:20:25As the day ends, the mayflies perform their swansong.
0:21:03 > 0:21:07The sand martins are so full they lose their edge and appetite.
0:21:18 > 0:21:21But their loss is another's gain.
0:21:41 > 0:21:46The biggest challenge for migrating birds is to keep on course.
0:21:47 > 0:21:51Like all birds, cranes use the sun as a compass.
0:21:51 > 0:21:56Her body clock even compensates as the sun arcs across the sky.
0:21:57 > 0:22:01If it's cloudy, she can navigate by the Earth's magnetic field
0:22:11 > 0:22:17But despite her state-of-the-art GPS, like us, she prefers to trust her eyes.
0:22:19 > 0:22:22From above, the land unfolds like a map
0:22:22 > 0:22:25and a river is the perfect line to follow.
0:22:39 > 0:22:43Chateau de Chenonceau is a reliable landmark.
0:23:10 > 0:23:13The Loire Valley is such a popular route,
0:23:13 > 0:23:1650,000 cranes can pass through in a single day.
0:23:25 > 0:23:28Many cranes that pass through this valley
0:23:28 > 0:23:31still have a thousand miles left to travel.
0:23:38 > 0:23:42But the storks are reaching the end of their journey.
0:23:51 > 0:23:57They took 50 days to fly from South Africa to their nest sites in this German village.
0:24:01 > 0:24:04The first male to arrive prepares to land.
0:24:11 > 0:24:15He whiffles, spilling air from his wings to get down quickly.
0:24:23 > 0:24:25He then jams on his air brakes
0:24:25 > 0:24:28by lowering his legs and flaring his feet.
0:24:56 > 0:24:59He's returning to his ancestral home,
0:24:59 > 0:25:03a nest that has been in his family for generations.
0:25:15 > 0:25:20But he faces competition. Younger males try to claim squatters' rights.
0:25:22 > 0:25:25He protects the nest as if it's a family heirloom.
0:25:39 > 0:25:41Soon all the arguments are over,
0:25:41 > 0:25:46and the males settle down to wait for their mates to arrive.
0:25:51 > 0:25:54To fill the time, they start a thorough spring-clean.
0:25:59 > 0:26:03They haven't seen their partners for eight months
0:26:03 > 0:26:06so it's vital to make a good impression.
0:26:20 > 0:26:23He preens himself ready for the grand reunion.
0:26:29 > 0:26:31Hopes are high.
0:26:34 > 0:26:39But so far, it's just swallows and house martins that are arriving.
0:26:42 > 0:26:46They set off from South Africa at the same time as the storks,
0:26:46 > 0:26:50but had to flap their wings all the way, instead of gliding on thermals.
0:26:55 > 0:26:58Like storks, the males arrive first.
0:27:10 > 0:27:14The storks could face an agonising wait for their mates.
0:27:14 > 0:27:17Migration is tough and some simply don't make it.
0:27:29 > 0:27:33Brent geese avoid all this heartache by flying together,
0:27:33 > 0:27:35as one big, happy family.
0:27:38 > 0:27:43Mum, Dad and the kids are all joined by uncles and aunts.
0:27:58 > 0:28:00The brent geese head northwards,
0:28:00 > 0:28:03just as other birds migrating from Africa arrive.
0:28:09 > 0:28:12Many flocks spend the winter on the coastal marshes
0:28:12 > 0:28:16around Mont St Michel in Northern France.
0:28:24 > 0:28:28But in spring, they leave for Arctic Russia.
0:28:49 > 0:28:51Many start their 3,000 mile journey
0:28:51 > 0:28:53by crossing the English Channel.
0:28:56 > 0:28:58Brent geese take a leisurely six weeks
0:28:58 > 0:29:03to reach their destination, stopping at least 16 times along the way.
0:29:09 > 0:29:13The famous White Cliffs of Dover are their first sight of Britain.
0:29:42 > 0:29:46As they leave, swallows are arriving for the summer.
0:29:52 > 0:29:56They flew 6,000 miles to return to the farm they were born in.
0:30:09 > 0:30:13Like storks, the male has some DIY to do.
0:30:17 > 0:30:20Some nests have been in the family for 50 years.
0:30:23 > 0:30:26Like all old properties, they need a spot of renovation.
0:30:33 > 0:30:36Those good at the job impress the females
0:30:36 > 0:30:38and are allowed to mate more often.
0:30:44 > 0:30:46The right materials are everything.
0:31:49 > 0:31:53Adding a few soft furnishings will improve his chances.
0:31:54 > 0:31:58It's the perfect way to feather his nest.
0:31:58 > 0:32:00And just in time.
0:32:01 > 0:32:05The female arrives and follows him for an inspection.
0:32:16 > 0:32:17She's impressed.
0:32:21 > 0:32:22For the house-proud couple,
0:32:22 > 0:32:26the migration has been a great success,
0:32:26 > 0:32:28but not all journeys go according to plan.
0:32:35 > 0:32:39London is hardly a top attraction for migrating birds.
0:32:43 > 0:32:46But many are forced to make an unscheduled stop,
0:32:46 > 0:32:50having suffered flight diversions due to bad weather.
0:32:51 > 0:32:54Barnacle geese are among the many waifs and strays
0:32:54 > 0:32:57that sometimes end up on the wrong side of town.
0:33:09 > 0:33:13Lost birds use their navigational skills to try to get back on track.
0:33:27 > 0:33:29For stray barnacle geese,
0:33:29 > 0:33:33the nearest UK population is 400 miles north in Scotland.
0:33:39 > 0:33:42The shortest route to join them is along the east coast of Britain.
0:34:21 > 0:34:24Just over the Scottish border is Bass Rock,
0:34:24 > 0:34:27the site of another great migration spectacle.
0:34:33 > 0:34:39Gannets have travelled 3,500 miles from West Africa just to be here.
0:34:41 > 0:34:45150,000 cram onto this one small outcrop.
0:34:52 > 0:34:56They are attracted to the rich North Sea fishing grounds
0:34:56 > 0:34:58that surround the island.
0:35:02 > 0:35:06The birds form a fishing fleet to be reckoned with.
0:35:06 > 0:35:11In one year, these gannets net 8,000 tonnes of fish between them.
0:35:39 > 0:35:41The gannets' fishing trips may last four days
0:35:41 > 0:35:44and take them 300 miles out to sea.
0:35:55 > 0:36:01They can submerge 22 metres in a dive, deeper than any other bird.
0:36:10 > 0:36:12They are cushioned from the impact
0:36:12 > 0:36:15by air sacs in their throat and breast.
0:36:19 > 0:36:23They slice though the water without slowing at all.
0:36:50 > 0:36:53Meanwhile, the barnacle geese will travel on north
0:36:53 > 0:36:55over the city of Edinburgh.
0:37:15 > 0:37:17They prefer to hug the coast
0:37:17 > 0:37:20but will move inland when they sense danger ahead.
0:37:25 > 0:37:28Falling air pressure warns of an approaching weather front.
0:37:32 > 0:37:36It may be safer inland but some storms are impossible to avoid.
0:37:39 > 0:37:40THUNDER CRASHES
0:38:10 > 0:38:12Thankfully, they're equipped
0:38:12 > 0:38:14with the best wet-weather gear imaginable.
0:38:19 > 0:38:22Their feathers interlock, creating a watertight seal,
0:38:22 > 0:38:26resistant to the driving rain pounding at 40 miles per hour.
0:38:30 > 0:38:32It's like water off a duck's back.
0:38:57 > 0:39:02But storms aren't the only challenges that geese encounter.
0:39:16 > 0:39:20The golden eagle, Scotland's deadliest aerial predator.
0:39:35 > 0:39:38The geese whiffle to lose height quickly.
0:39:42 > 0:39:44Eagles are formidable hunters.
0:39:46 > 0:39:49But suddenly it's the hunter that's under attack.
0:39:51 > 0:39:55Crows mob any predator that dares invade their territory.
0:39:58 > 0:40:00The geese hightail it.
0:40:11 > 0:40:14The eagle gets his comeuppance for once,
0:40:14 > 0:40:16put in his place by a lowly crow.
0:40:30 > 0:40:34The barnacle geese head northwest along Loch Ness.
0:40:50 > 0:40:53Then, just ahead, a gathering of other geese,
0:40:53 > 0:40:57exactly what a lost flock needs.
0:40:57 > 0:41:00The massed birds are waiting for a weather window
0:41:00 > 0:41:02that will allow them to leave for the Arctic.
0:41:12 > 0:41:16They use the time to pile on the pounds.
0:41:24 > 0:41:26But they have a problem.
0:41:29 > 0:41:33Spring is the time of mad March hares
0:41:33 > 0:41:36and the geese are bang in the middle of their boxing ring.
0:41:50 > 0:41:54Females don't pull any punches fending off over-eager males.
0:42:04 > 0:42:07Boxing hares are a sign that the geese should leave.
0:42:16 > 0:42:17With a fair wind blowing,
0:42:17 > 0:42:21the mad March hares kick-start the goose migration.
0:42:23 > 0:42:26The race to the high Arctic is on.
0:42:32 > 0:42:36Ahead lies a non-stop, 1,500-mile sea crossing.
0:42:40 > 0:42:44The decision to leave is the most important they make.
0:42:44 > 0:42:46Getting the forecast wrong could cost them their lives.
0:42:50 > 0:42:55Once at sea, the nearest land is 400 miles to the northeast in Scandinavia.
0:43:01 > 0:43:03Even these far reaches of Europe
0:43:03 > 0:43:06attract birds that over-wintered in Africa.
0:43:10 > 0:43:14Many ospreys make the northern forests of Finland their summer home,
0:43:14 > 0:43:17travelling over 4,000 miles to get here.
0:43:19 > 0:43:22Good fishing ponds are scattered throughout the forests,
0:43:22 > 0:43:25making it a popular place to nest.
0:43:36 > 0:43:39Brown bears are here for the fishing too.
0:44:00 > 0:44:02It's an angler's paradise.
0:44:25 > 0:44:28There's always one that gets away!
0:44:28 > 0:44:30BEAR GROWLS
0:44:38 > 0:44:41Success this time.
0:44:41 > 0:44:42GROWLING AND GRUNTING
0:44:44 > 0:44:47It's this superabundance of fish
0:44:47 > 0:44:51that makes their 45-day journey here worth all the effort.
0:44:56 > 0:44:58BIRD CHIRRUPS
0:45:06 > 0:45:09BEAR GRUNTS
0:45:12 > 0:45:15Ospreys have favourite feeding perches
0:45:15 > 0:45:17which they return to time and again.
0:45:22 > 0:45:24BEAR GROWLS
0:45:26 > 0:45:29A mother bear knows just where they are...
0:45:34 > 0:45:36GROWLING
0:45:39 > 0:45:41..and so do cubs.
0:45:42 > 0:45:45GRUNTING
0:45:56 > 0:45:58But ospreys are messy eaters.
0:45:58 > 0:46:01They usually leave a few scraps behind.
0:46:05 > 0:46:06It's the perfect snack
0:46:06 > 0:46:08for a hungry bear.
0:46:12 > 0:46:15For the osprey, there's plenty more fish in the pond.
0:46:56 > 0:47:01Further south, the bulb fields of Holland bring a patchwork of colour
0:47:01 > 0:47:04to a landscape reclaimed by man from salt marshes.
0:47:21 > 0:47:24In the past, cranes would have stopped here to breed.
0:47:24 > 0:47:26Now they just keep on travelling.
0:47:31 > 0:47:34In Europe, migrating birds have to be adaptable.
0:47:38 > 0:47:42Until recently, windmills adorned the landscape.
0:47:42 > 0:47:45It's now wind turbines instead.
0:47:48 > 0:47:51Although wind farms can be dangerous in bad weather,
0:47:51 > 0:47:54birds are usually canny enough to avoid them.
0:48:02 > 0:48:07Mother cranes have no problem steering their families safely through the hazards.
0:48:07 > 0:48:11They have an appointment to make and they must keep them moving.
0:48:11 > 0:48:12CRANES HONK
0:48:21 > 0:48:23They travelled 3,000 miles
0:48:23 > 0:48:27to reach a very special patch of marsh in Sweden.
0:48:31 > 0:48:34They join thousands of other families
0:48:34 > 0:48:36that have also made the rendezvous on time.
0:48:47 > 0:48:51This is the most important social event in the cranes' calendar.
0:49:21 > 0:49:24For the parents, it's a place to renew their vows.
0:49:24 > 0:49:27HONKING
0:49:27 > 0:49:31They call in unison, a synchronised duet that gets them in the mood.
0:49:35 > 0:49:38But the youngsters are also searching for a soul mate.
0:49:40 > 0:49:43This young female seems free.
0:49:44 > 0:49:47Time for a young male to make his move.
0:49:57 > 0:50:00He must dance to win her heart.
0:50:05 > 0:50:07She's hard to impress.
0:50:07 > 0:50:10He will have to raise his game if he's to be taken seriously.
0:50:10 > 0:50:12HONKING
0:50:16 > 0:50:20Good dance moves demand practice and determination.
0:50:28 > 0:50:32He rehearses his vertical leaps, hoping to impress.
0:50:56 > 0:50:58Her interest is piqued.
0:51:10 > 0:51:12His efforts pay off.
0:51:12 > 0:51:15Now an item, they dance together.
0:51:22 > 0:51:25Their synchronised routine ties the knot.
0:51:35 > 0:51:39Their enthusiasm is infectious. It triggers a mass dance-off.
0:51:46 > 0:51:48The happy couple leave the party early
0:51:48 > 0:51:50to start their new life together.
0:51:52 > 0:51:55And the dance goes on without them.
0:52:18 > 0:52:23Barnacle geese fly continuously for days to reach the Arctic Ocean.
0:52:25 > 0:52:26It's hard work.
0:52:26 > 0:52:30For every breath they take, their wings will beat three times.
0:52:35 > 0:52:39Once the fat reserves are gone, they will start burning muscle.
0:52:40 > 0:52:44The last few miles are the hardest but the destination is in sight.
0:52:45 > 0:52:50The Svalbard archipelago, midway between Norway and the North Pole.
0:53:02 > 0:53:07Europe's furthest wilderness may look a barren wasteland to us
0:53:07 > 0:53:10but it's paradise for the geese.
0:53:24 > 0:53:2824 hours of daylight provide all the grazing time they need
0:53:28 > 0:53:31as they prepare to mate and lay eggs.
0:53:35 > 0:53:37Back in the stork village,
0:53:37 > 0:53:40the return of the females hasn't gone to plan.
0:53:40 > 0:53:42The males are still waiting.
0:53:42 > 0:53:48When weather conditions are bad, whole flocks can get lost at sea.
0:53:49 > 0:53:51But things are looking up.
0:54:00 > 0:54:01The girls are back in town.
0:54:04 > 0:54:07The males can't contain their excitement.
0:54:10 > 0:54:13CLATTERING OF BEAKS
0:54:16 > 0:54:20She remembers the location of her nest and drops down to greet him.
0:54:27 > 0:54:29CLATTERING OF BEAKS
0:54:34 > 0:54:37Together at last, they clatter a greeting.
0:54:40 > 0:54:44In Africa, they spent eight months apart.
0:54:44 > 0:54:47Now they must get to know each other again.
0:54:56 > 0:54:59Back on Svalbard, the barnacle geese
0:54:59 > 0:55:01are already experiencing a baby boom.
0:55:12 > 0:55:14But this attracts a rare visitor.
0:55:37 > 0:55:40And chicks make a tasty snack.
0:55:53 > 0:55:57Mothers desperately shepherd their young to safety.
0:56:03 > 0:56:07A lost chick is the first to go.
0:56:08 > 0:56:10THEY HONK
0:56:10 > 0:56:12And then another.
0:56:13 > 0:56:17The geese launch a counter-attack but they can't manoeuvre easily.
0:56:17 > 0:56:19HONKING AND GRUNTING
0:56:23 > 0:56:26A hungry polar bear can wipe out an entire colony.
0:56:30 > 0:56:32They desperately need reinforcements.
0:56:35 > 0:56:40Nesting Arctic terns join the aerial assault, united by a common enemy.
0:56:42 > 0:56:45Their plan is to make the bear's life a misery.
0:56:45 > 0:56:47CHIRRUPING
0:56:49 > 0:56:51More join the attack.
0:56:51 > 0:56:52HONKING
0:56:54 > 0:56:57The bear's irritation starts to show.
0:56:57 > 0:56:59BEAR GROWLS
0:56:59 > 0:57:02Skuas join the combat mission.
0:57:02 > 0:57:05Faster and more aggressive, they drive home the attack.
0:57:05 > 0:57:07BEAR GROWLS
0:57:23 > 0:57:27Working together, the birds have saved the colony.
0:57:31 > 0:57:34Although meeting polar bears is an increasing problem,
0:57:34 > 0:57:38by nesting in the Arctic, the geese avoid human disturbance altogether.
0:57:42 > 0:57:45But storks are among the many birds that deliberately seek us out.
0:57:45 > 0:57:49They raise their young among us, in the very heart of Europe.
0:58:00 > 0:58:03Like so many birds, they have managed to prosper
0:58:03 > 0:58:06in a continent that we have changed more than any other.
0:58:19 > 0:58:23Next time, condors and macaws will take us on an extraordinary journey
0:58:23 > 0:58:28to discover the hidden secrets of the South American continent.
0:58:39 > 0:58:42Subtitles by Red Bee Media Ltd
0:58:42 > 0:58:45E-mail subtitling@bbc.co.uk