0:00:04 > 0:00:09On the edge of the Atlantic lies a world of rock and water.
0:00:18 > 0:00:23Wind-scoured and rugged, yet full of grace and beauty.
0:00:33 > 0:00:38Exposed to a restless ocean and Europe's wildest weather,
0:00:38 > 0:00:42the animals of these islands face challenge after challenge.
0:00:52 > 0:00:56For a year, we'll follow life in this magical
0:00:56 > 0:00:58but unpredictable place...
0:01:08 > 0:01:10..revealing secret lives...
0:01:12 > 0:01:14..and mysterious worlds...
0:01:25 > 0:01:27..rarely seen...
0:01:30 > 0:01:32...and never filmed here before.
0:01:38 > 0:01:42Here on Scotland's wild west coast..
0:01:47 > 0:01:52..here in the Hebrides!
0:02:10 > 0:02:15In Britain, the Outer Hebrides are as far west as you can go.
0:02:15 > 0:02:18Of all the islands on the edge,
0:02:18 > 0:02:22these are the most exposed to the raw power of the Atlantic.
0:02:36 > 0:02:38They form a long chain,
0:02:38 > 0:02:39and carry an ancient
0:02:39 > 0:02:41sense of place in their names.
0:02:43 > 0:02:45Berneray,
0:02:45 > 0:02:47Benbecula,
0:02:47 > 0:02:50Uist,
0:02:50 > 0:02:52Lewis,
0:02:52 > 0:02:57and Harris, with mountains made from the same rock as the moon.
0:03:02 > 0:03:05There's an otherworldliness here
0:03:05 > 0:03:08that sets these islands apart from anywhere else in Europe.
0:03:18 > 0:03:23Along this final frontier are even more remote satellites -
0:03:24 > 0:03:28outlying rocks and stacks,
0:03:28 > 0:03:32and these reveal why the Outer Hebrides are so special.
0:03:38 > 0:03:42On these islands are some of the largest seabird colonies in Europe.
0:03:48 > 0:03:53Northern gannets alone number more than 100,000 birds...
0:03:57 > 0:04:00..the greatest gathering on the planet.
0:04:30 > 0:04:33It's mid-June and all the Hebridean seabirds
0:04:33 > 0:04:36have just a few short months to raise a family.
0:04:49 > 0:04:54Summer is brief here, even by Scottish standards,
0:04:54 > 0:04:57and this year the weather has been particularly cruel.
0:05:07 > 0:05:11In Spring, the Hebrides were hit by a devastating storm,
0:05:11 > 0:05:14the worst for many years.
0:05:32 > 0:05:34Its effect was catastrophic.
0:05:38 > 0:05:41Many birds lost eggs and nests, they had to put their breeding
0:05:41 > 0:05:44season on hold, just as it was starting.
0:05:49 > 0:05:53An already brief summer is now even shorter.
0:06:15 > 0:06:18On the outlying islands there's a real sense of urgency
0:06:18 > 0:06:20in the huge puffin colonies.
0:06:29 > 0:06:34The torrential rain flooded many burrows,
0:06:34 > 0:06:37and it's been hard work digging them out again.
0:06:40 > 0:06:42Deep in the back of this burrow
0:06:42 > 0:06:46nestles a single, three-week-old chick - a puffling.
0:06:49 > 0:06:55Her parents have been together for many years.
0:06:55 > 0:06:59They constantly re-affirm their bond with ritualized head-flicking.
0:07:09 > 0:07:13Every day they fly out to sea to bring her food,
0:07:13 > 0:07:16each clocking up to a hundred kilometres.
0:07:24 > 0:07:27Because of the setbacks this year,
0:07:27 > 0:07:30the parents are under even greater pressure than usual.
0:07:30 > 0:07:32They must feed the puffling quickly and often,
0:07:32 > 0:07:35so she'll be ready to leave by autumn.
0:07:37 > 0:07:39And there's another problem.
0:07:39 > 0:07:42Great skuas - locally known as bonxies,
0:07:42 > 0:07:44make a living mugging other seabirds.
0:07:55 > 0:07:59They can bully gannets twice their size into coughing up their catch.
0:08:17 > 0:08:20At a third of the skua's weight, puffins are a pushover.
0:08:23 > 0:08:25The bonxies prowl the colony,
0:08:25 > 0:08:27seizing any opportunity that comes their way.
0:08:35 > 0:08:38They're quite capable of dragging a puffling
0:08:38 > 0:08:40from its hole and devouring it...
0:08:43 > 0:08:46..so the chick must stay well-clear of the entrance.
0:08:55 > 0:08:57For thousands of years,
0:08:57 > 0:09:02the seas around these islands have sustained not just seabirds,
0:09:02 > 0:09:04but people.
0:09:07 > 0:09:10On the east coast of the Isle of Lewis,
0:09:10 > 0:09:13sheltered from Atlantic gales, lies the town of Stornoway.
0:09:16 > 0:09:19It's easily the best harbour in the Outer Hebrides.
0:09:27 > 0:09:31In the days when travelling across Europe was slow and dangerous,
0:09:31 > 0:09:35Stornoway was an important crossroads for people using the sea.
0:09:39 > 0:09:43Bronze-age traders, Celts and Vikings all came here
0:09:43 > 0:09:45and made this a cosmopolitan place.
0:09:50 > 0:09:54Even the town's name comes from the ancient tongue of the Vikings.
0:10:02 > 0:10:05Stornoway has always been an important fishing port
0:10:05 > 0:10:07and it's still home to many boats.
0:10:24 > 0:10:26A group of grey seals hangs out in the harbour
0:10:26 > 0:10:28waiting for the returning fleet.
0:10:35 > 0:10:39This mature bull has realised that the boats can supply him
0:10:39 > 0:10:42with a free fish supper.
0:10:54 > 0:10:58Living here certainly means you don't need to work too hard
0:10:58 > 0:11:00to earn regular meals.
0:11:07 > 0:11:08Back in the puffin colony,
0:11:08 > 0:11:11getting a meal is a matter of life and death.
0:11:13 > 0:11:16The bonxies are hunting hard. They're hungry, too.
0:11:18 > 0:11:23The three-week-old puffling is keeping safe at the back of the burrow.
0:11:25 > 0:11:29But another youngster has made a fatal mistake.
0:11:45 > 0:11:47It's a lucky escape for the puffling...
0:11:52 > 0:11:55..but now the bonxies turn their attention to its parents.
0:12:07 > 0:12:11To deliver this precious catch, they have to run the gauntlet.
0:12:56 > 0:13:00Every time they feed their puffling, it's a triumph!
0:13:11 > 0:13:14The chicks which survive can live for more than 30 years -
0:13:17 > 0:13:20little birds with a lot of experience.
0:13:50 > 0:13:55The seas around the Outer Hebrides are rich,
0:13:55 > 0:13:58and despite the storms earlier in the year,
0:13:58 > 0:14:01it's turning out to be an exceptionally good year for fish.
0:14:27 > 0:14:32There's plenty of food here to support large shoals.
0:14:35 > 0:14:38But you still have to know where to find them.
0:14:52 > 0:14:54In the sound of Barra,
0:14:54 > 0:14:58a pod of 15 bottlenose dolphins know all the tricks of the trade.
0:15:14 > 0:15:18They can read these complex tidal waters as only true residents can.
0:15:25 > 0:15:29Sometimes they save energy by bow-riding fishing boats
0:15:29 > 0:15:31which are going the same way.
0:15:33 > 0:15:36After all, fishermen need to read the currents and tides, too.
0:15:44 > 0:15:48This pod will work these waters all summer,
0:15:48 > 0:15:50making the most of this short time of plenty.
0:16:07 > 0:16:11Now the local residents are joined by long-distance travellers.
0:16:17 > 0:16:19Missing the spring storms by just a few weeks,
0:16:19 > 0:16:26a flock of migrants arrives on the warm south wind - Arctic Terns.
0:16:35 > 0:16:40They've flown almost 19,000 kilometres from the Antarctic to the island of Lewis.
0:16:56 > 0:17:00Here, just north of Stornoway town, they're checking out
0:17:00 > 0:17:03a small river island, rich with blooming sea pinks.
0:17:11 > 0:17:15It seems ideal - there are no ground predators here,
0:17:15 > 0:17:18and on the doorstep is a great source of food.
0:17:24 > 0:17:26Broad Bay is sheltered
0:17:26 > 0:17:30and the many animals already feeding here are proof of how rich it is.
0:17:38 > 0:17:43Otters fish the rising tide
0:17:43 > 0:17:45while eider ducks dive for mussels.
0:18:02 > 0:18:04The terns decide to settle here.
0:18:11 > 0:18:14They explore the river island, working out where they want to nest.
0:18:23 > 0:18:28Terns, like so many seabirds, mate for life.
0:18:28 > 0:18:31And these kinds of decisions take time.
0:18:42 > 0:18:45After coming so far, they might as well get it right!
0:18:57 > 0:19:02Now that's done, the male needs to cement their relationship.
0:19:02 > 0:19:05All he has to do is to head out into the Bay,
0:19:05 > 0:19:07and find a small gift for his mate.
0:19:20 > 0:19:22Shrimps are too slippery.
0:19:26 > 0:19:32A plump sand eel, from further out, might be better,
0:19:32 > 0:19:35once he's got a good grip.
0:19:35 > 0:19:37Now it's just a case of getting it back home.
0:19:39 > 0:19:43But once again, there are pirates waiting in the wings.
0:19:56 > 0:20:01This time, they're arctic skuas - swift, manoeuvrable and persistent.
0:20:14 > 0:20:17A bonxie moves in on the colony.
0:20:17 > 0:20:18This needs teamwork.
0:20:42 > 0:20:45But it's all worth it to hand over the prize.
0:21:05 > 0:21:09There's a good reason that nesting birds cling to the islands' edges.
0:21:16 > 0:21:19The interior of Lewis is vast,
0:21:19 > 0:21:21but it's not fertile like the surrounding seas.
0:21:29 > 0:21:31Lashed by strong westerlies,
0:21:31 > 0:21:35the rocks are covered by layers of peat and studded with small lochs.
0:21:52 > 0:21:55Fish don't thrive in these isolated pools
0:21:55 > 0:21:57and that's good for damselflies.
0:22:00 > 0:22:04Their vulnerable young live underwater.
0:22:04 > 0:22:07But first they have to get there - and that means laying eggs.
0:22:18 > 0:22:21On one of the first really warm days of summer,
0:22:21 > 0:22:24a male damselfly has found a mate and the pair lock together.
0:22:30 > 0:22:34She needs his help to break through the surface, so he's pushing her under.
0:22:40 > 0:22:42But he's slipped.
0:22:50 > 0:22:52And then, disaster!
0:22:52 > 0:22:54A gust of wind breaks them apart.
0:22:59 > 0:23:02He can't help her now but she presses on alone.
0:23:06 > 0:23:10Underwater, she must split open the stem and lay her eggs.
0:23:10 > 0:23:12But getting out again without the male's help
0:23:12 > 0:23:14is going to be very tricky.
0:23:20 > 0:23:23On the other side of the pool, one of Britain's rarest birds
0:23:23 > 0:23:25sits on recently laid eggs -
0:23:26 > 0:23:29a red-throated diver!
0:23:31 > 0:23:34This pair's first nest was washed away by the storms.
0:23:34 > 0:23:37This is their only chance to raise young this year.
0:23:50 > 0:23:53The watery world of the Western Isles is vital to the divers.
0:23:58 > 0:24:01Their legs are so well adapted for swimming
0:24:01 > 0:24:03that they can't walk properly,
0:24:03 > 0:24:08so they can only nest right on the edges of pools like this.
0:24:08 > 0:24:11And that makes changeovers a clumsy affair,
0:24:11 > 0:24:13more like falling in and out of bed.
0:24:21 > 0:24:25While the female takes her turn on the eggs,
0:24:25 > 0:24:27the male heads out to sea in search of fish.
0:24:33 > 0:24:37But while he's away, the female is exposed to danger.
0:24:43 > 0:24:47It's a black-throated diver - bigger,
0:24:47 > 0:24:50more powerful, and looking for a new home.
0:24:59 > 0:25:03At the edge of the lochan, a damsel is in distress.
0:25:07 > 0:25:11The female damselfly can't break free of the water's surface
0:25:11 > 0:25:13without the male to help her.
0:25:16 > 0:25:19But then she manages to flip a wing up -
0:25:19 > 0:25:21and another!
0:25:21 > 0:25:24And like tiny sails, they catch the breeze.
0:25:38 > 0:25:42Predatory dragonfly larvae are close by.
0:25:42 > 0:25:45They'll kill her if they notice she's there.
0:25:53 > 0:25:56She's drifted against a stem.
0:25:56 > 0:25:58It gives her some leverage out of the water,
0:25:58 > 0:26:02and, at last, a safe place to dry out.
0:26:04 > 0:26:07But she still has more eggs to lay,
0:26:07 > 0:26:10so tomorrow she'll go through it all over again.
0:26:14 > 0:26:15The male red-throated diver
0:26:15 > 0:26:19arrives back and discovers the blackthroat on his lochan.
0:26:27 > 0:26:31The smaller diver starts to panic
0:26:31 > 0:26:34but it must defend the female on the nest.
0:26:50 > 0:26:52For all their ungainliness above water,
0:26:52 > 0:26:55these birds are like torpedoes underneath.
0:26:58 > 0:27:02Their bills are like knives - a stab from below could be lethal.
0:27:33 > 0:27:38The commotion draws the female redthroat off the nest to help her mate.
0:27:38 > 0:27:42But the blackthroat is heading straight towards her.
0:27:53 > 0:27:55And suddenly they're on top of one another.
0:28:00 > 0:28:03The blackthroat is taken completely by surprise...
0:28:08 > 0:28:10..and the female redthroat seizes
0:28:10 > 0:28:12the chance to lure the intruder away.
0:28:21 > 0:28:22It's all too much.
0:28:23 > 0:28:26Rattled, the blackthroat makes a hasty exit.
0:28:33 > 0:28:37It's back on the eggs as quickly as possible.
0:28:37 > 0:28:41If they're left too long, they'll chill and won't hatch.
0:28:56 > 0:28:57It's early July.
0:28:58 > 0:29:00With 18 hours of daylight,
0:29:00 > 0:29:03conditions are perfect for growing crops.
0:29:09 > 0:29:12But even now, farming in the Outer Hebrides is never easy.
0:29:16 > 0:29:21The islands of Uist and Benbecula appear the most unforgiving.
0:29:23 > 0:29:27Scraped by long-gone glaciers, they're now as much water as land.
0:29:38 > 0:29:40But running down the Atlantic side
0:29:40 > 0:29:43of the islands is one of the jewels of the Hebrides...
0:29:52 > 0:29:54..the machair.
0:30:02 > 0:30:05Lying between the unfertile moorland and the sea,
0:30:05 > 0:30:07it's like a Scottish Garden of Eden.
0:30:26 > 0:30:29Over centuries, the winds have blown shell-sand up onto the islands,
0:30:29 > 0:30:31balancing out the acid of the peat.
0:30:53 > 0:30:56But the machair wouldn't be this rich if it wasn't for people.
0:31:02 > 0:31:05Generations of crofters have carried seaweed onto the land
0:31:05 > 0:31:07to make it more fertile,
0:31:07 > 0:31:10and they leave the small fields fallow in some years -
0:31:10 > 0:31:14allowing wild flowers, insects and birds to move in.
0:31:19 > 0:31:22In high summer, the machair hums with rare bees
0:31:22 > 0:31:24like the moss carder
0:31:24 > 0:31:28and the great yellow bumblebee - extinct in most of mainland Britain.
0:31:33 > 0:31:37Meadows like this hardly exist there any more because of intensive farming.
0:31:42 > 0:31:46There are always corners for the corncrake -
0:31:46 > 0:31:50whose surreal rasping call is heard almost nowhere else in Britain.
0:31:50 > 0:31:52It's flourishing here in the Uists.
0:32:01 > 0:32:05The rich supply of insects makes this an ideal home for skylarks.
0:32:08 > 0:32:11Their nest is well hidden amongst the flowers.
0:32:14 > 0:32:16The chicks are brilliantly camouflaged
0:32:16 > 0:32:19with tendril-like feathers on their heads
0:32:19 > 0:32:21helping them blend in with the grass.
0:32:31 > 0:32:34The machair is also globally important
0:32:34 > 0:32:39because it's home for birds like lapwings which nest on the ground.
0:32:44 > 0:32:48In a normal year, they'd have finished raising their chicks by now,
0:32:48 > 0:32:52but they were also hit by the storms.
0:32:52 > 0:32:55So along with other local residents like redshanks
0:32:55 > 0:33:00and oystercatchers, they're sharing the machair with recently arrived migrants.
0:33:07 > 0:33:09It's much more crowded than usual
0:33:09 > 0:33:13and the lapwings are kept busy defending their patch.
0:33:30 > 0:33:33Wader chicks hatch fully fluffed-up and ready to go.
0:33:43 > 0:33:47It's like keeping control of half a dozen wayward toddlers all at once.
0:33:53 > 0:33:56The mother lapwing has a real job on her hands
0:33:56 > 0:33:58to keep her brood together - and safe.
0:34:13 > 0:34:18Living in this world of rock and water is tough for people and animals alike.
0:34:20 > 0:34:25But in the Outer Hebrides, people have found remarkable ways of surviving.
0:34:31 > 0:34:35The most unusual human community of all lay on a group of islands
0:34:35 > 0:34:3840 miles to the west of the Uist machair...
0:34:46 > 0:34:48..St Kilda.
0:35:01 > 0:35:06The islanders who lived here were the last pure hunting community in Britain.
0:35:10 > 0:35:15Living almost entirely on a diet of puffins, gannets and fulmars,
0:35:15 > 0:35:20they'd think nothing of scaling the thousand-foot cliffs barefoot to harvest the seabirds.
0:35:26 > 0:35:33These cliffs still support the biggest seabird colonies in Western Europe.
0:35:36 > 0:35:38The fang-like Stacs are home
0:35:38 > 0:35:41to the single largest gannet colony on the planet.
0:35:43 > 0:35:46One fifth of the world population lives here.
0:35:55 > 0:35:57Now in mid-July,
0:35:57 > 0:36:01the colony is full of plump young gannets locally known as gugas.
0:36:04 > 0:36:07They were a key food for the St Kildans
0:36:07 > 0:36:10and are still sometimes eaten in parts of the Outer Hebrides.
0:36:25 > 0:36:29The St Kildans' way of life was so unusual and self-contained,
0:36:29 > 0:36:33it simply couldn't survive contact with the modern world.
0:36:40 > 0:36:45Worn down by disease and the loss of fit young people to a life
0:36:45 > 0:36:50over the sea, the last 36 islanders asked to be evacuated in 1930.
0:36:57 > 0:37:01Their community could adapt no further,
0:37:01 > 0:37:07but they left other inhabitants behind - and they ARE changing.
0:37:07 > 0:37:11Like a Scottish Galapagos, St Kilda now gives scientists a chance
0:37:11 > 0:37:13to watch evolution in action.
0:37:20 > 0:37:23The wrens on St Kilda can't fly strongly enough to leave,
0:37:23 > 0:37:26and they're growing larger.
0:37:26 > 0:37:29They're now 25% heavier than their mainland cousins.
0:37:32 > 0:37:36They have a deeper song and lay larger eggs, too.
0:37:36 > 0:37:39Maybe they've had to toughen-up to these exposed conditions.
0:37:46 > 0:37:49The islanders' Soay sheep are changing too,
0:37:49 > 0:37:52but in the opposite direction - they're shrinking.
0:38:00 > 0:38:05Like red deer, they have an autumn rutting season, and these pint-sized
0:38:05 > 0:38:09rams are preparing themselves by sparring on the hillside.
0:38:22 > 0:38:26The island has a field mouse too, but it's moved into the village,
0:38:26 > 0:38:31finding homes in the dry-stone walls and houses.
0:38:31 > 0:38:36But needs must, as every castaway knows, and the mice have
0:38:36 > 0:38:40turned into carnivores - feeding on dead sheep and seabirds.
0:38:52 > 0:38:55They're also growing larger.
0:38:59 > 0:39:02Could St Kilda be seeing the evolution
0:39:02 > 0:39:04of a giant sheep-hunting rodent?
0:39:05 > 0:39:07IT ROARS
0:39:09 > 0:39:10Perhaps not!
0:39:16 > 0:39:21Sitting under its veil of cloud, St Kilda is rarely dry and sunny.
0:39:24 > 0:39:26But back on the machair, it's a different story.
0:39:52 > 0:39:54The unseasonal spring storms have been
0:39:54 > 0:39:57followed by one of the driest summers in living memory.
0:39:59 > 0:40:01It hasn't rained for weeks.
0:40:08 > 0:40:11Throughout July, the ground-nesting birds work frantically.
0:40:15 > 0:40:17The skylark chicks that seemed so small and defenceless
0:40:17 > 0:40:21just weeks ago are now chasing their parents for food.
0:40:31 > 0:40:33The plants are wilting,
0:40:33 > 0:40:36but there's still plenty of insects for the many young wading birds.
0:40:40 > 0:40:42They're growing fast, but still can't fly.
0:40:45 > 0:40:48The lapwing chicks have grown, but the brood is down to just two.
0:40:49 > 0:40:51It's a bigger loss of life than you'd expect
0:40:51 > 0:40:54in a place without ground predators.
0:40:54 > 0:40:55It's suspicious.
0:40:58 > 0:41:01BIRDS CALL
0:41:01 > 0:41:03The alarm goes up.
0:41:15 > 0:41:19A ferret, an escaped domestic animal,
0:41:19 > 0:41:21is on the loose and causing chaos.
0:41:35 > 0:41:37The waders mob it,
0:41:37 > 0:41:40trying to drive it away from their flightless chicks.
0:41:41 > 0:41:44But it's too late, it's got one.
0:41:48 > 0:41:51It vanishes into the long grass, but the damage is done.
0:42:04 > 0:42:08Introduced animals like ferrets can cause havoc in this fragile place...
0:42:10 > 0:42:12..but that's not the only problem.
0:42:15 > 0:42:18The Uist machair is less than two metres above sea level
0:42:18 > 0:42:19in many places.
0:42:26 > 0:42:31Now the climate is changing, and with it, the sea is slowly rising.
0:42:31 > 0:42:33These low-lying islands
0:42:33 > 0:42:35are in danger of being claimed by the ocean.
0:42:42 > 0:42:45Here, where change is a fact of life,
0:42:45 > 0:42:49they say, "what the wind brings, the current takes away".
0:42:56 > 0:43:00It's a reminder that, whatever we might like to believe, living here,
0:43:00 > 0:43:04on the outermost edge of the Hebrides, is on the ocean's terms.
0:43:47 > 0:43:50It's August, and the Outer Hebrides appear almost tropical
0:43:50 > 0:43:52as the sun beats down day after day.
0:44:09 > 0:44:11The drought is causing a real problem...
0:44:12 > 0:44:14..for Atlantic salmon.
0:44:18 > 0:44:21After a life at sea, they're gathering by the mouth
0:44:21 > 0:44:25of their home river, close to Amhuinnsuidhe Castle on Harris.
0:44:29 > 0:44:33To complete their life cycle, they need to swim upstream to spawn.
0:44:38 > 0:44:41They've travelled here from Greenland to do this...
0:44:44 > 0:44:47..but the last stage of their long journey is impossible,
0:44:47 > 0:44:48as the river is too low.
0:44:56 > 0:44:59It's not a problem for dippers.
0:44:59 > 0:45:02They work the river bed for insects which thrive in the bubbling water.
0:45:19 > 0:45:22Unable to advance, the waiting salmon are being picked off
0:45:22 > 0:45:23by grey seals.
0:45:31 > 0:45:33It'll take a great deal of rain
0:45:33 > 0:45:35to raise the river enough for the fish to advance.
0:45:45 > 0:45:48In the hills above the castle, a family of red-throated divers
0:45:48 > 0:45:50are also at a turning point in their lives.
0:45:55 > 0:45:58The two chicks are growing fast and they're hungry.
0:45:59 > 0:46:01But one is larger and more aggressive.
0:46:06 > 0:46:09It's quite rare for a second chick to even get this far.
0:46:11 > 0:46:15Usually, it would lose out on most of the feeds and die.
0:46:22 > 0:46:25But fish have been so plentiful this year
0:46:25 > 0:46:27that both chicks are almost ready to head out to sea.
0:46:36 > 0:46:38They just need to learn how to fly.
0:46:48 > 0:46:50The parents take off and land
0:46:50 > 0:46:52to show their youngsters exactly how it's done.
0:46:55 > 0:46:58But it's a challenging skill to master.
0:47:03 > 0:47:05This chick still has some way to go.
0:47:28 > 0:47:30You also need a lot of extra lift
0:47:30 > 0:47:34when your home is surrounded by mountains this steep.
0:47:44 > 0:47:45Nearly.
0:47:50 > 0:47:52THUNDERCLAP
0:47:52 > 0:47:55They don't have long. There's a change in the air.
0:47:56 > 0:47:58Autumn will be closing in soon.
0:48:01 > 0:48:05THUNDERCLAP
0:48:05 > 0:48:07Storm clouds are building.
0:48:14 > 0:48:19In a narrow sea loch in South Uist, 60 pilot whales have become trapped.
0:48:23 > 0:48:26They're creatures of the open ocean, but they may have followed
0:48:26 > 0:48:29a shoal of squid into this dangerous place.
0:48:39 > 0:48:41It's not good.
0:48:41 > 0:48:43They're not used to being hemmed in like this,
0:48:43 > 0:48:45and the younger whales are starting to panic.
0:49:05 > 0:49:08Several have cut themselves on the sharp rocks.
0:49:17 > 0:49:18Their distress grows.
0:49:21 > 0:49:23The shore is dangerously close.
0:49:26 > 0:49:28Stranding is now a real possibility.
0:49:35 > 0:49:37But luck is on their side.
0:49:37 > 0:49:41The tide is rising, opening the door of their prison,
0:49:41 > 0:49:45and the pod starts to move back towards safety in the open ocean.
0:49:53 > 0:49:56It's almost a relief, after four weeks of drought,
0:49:56 > 0:49:59when normal Hebridean weather returns.
0:50:28 > 0:50:31High in the mountains of Harris, the rivers are swelling,
0:50:31 > 0:50:33and the water thunders towards the sea.
0:51:04 > 0:51:06The salmon are finally on their way.
0:52:09 > 0:52:12The summer rain has replenished the machair lands, too.
0:52:14 > 0:52:17Crops are ripening as the wild flowers set seed.
0:52:27 > 0:52:30In the Uists, crofters will soon be bringing the harvest in.
0:52:33 > 0:52:35But there's always seed to spare for small mammals,
0:52:35 > 0:52:37which is good news for birds of prey.
0:52:48 > 0:52:50A recently fledged short-eared owl chick watches
0:52:50 > 0:52:55one of its parents quarter the fields, hunting for mice and voles.
0:53:03 > 0:53:05The machair is quieter now.
0:53:06 > 0:53:09The wading birds have moved off the fields, and onto the beach.
0:53:23 > 0:53:26Seaweed, washed up by the spring storm,
0:53:26 > 0:53:28is rotting quickly in the midsummer heat.
0:53:31 > 0:53:33Hordes of insects have been attracted in
0:53:33 > 0:53:34to feed on the decaying piles.
0:53:43 > 0:53:45Springtails eat bacteria that break down the kelp.
0:53:54 > 0:53:58As the tide sweeps in, they swarm into clusters.
0:54:03 > 0:54:06On the surface, they're fair game for passing terns.
0:54:22 > 0:54:26In time, these piles of kelp will be laid on the machair,
0:54:26 > 0:54:30and the richness of the ocean will revitalise the crofters' fields.
0:54:39 > 0:54:42It's September, and across the Uists,
0:54:42 > 0:54:44ancient machinery grinds into life.
0:54:49 > 0:54:50It's harvest time.
0:55:13 > 0:55:16Once the crops are cut, they're gathered into sheaves,
0:55:16 > 0:55:19and then piled into stooks and stacks.
0:55:20 > 0:55:24It's a system practiced here for centuries.
0:55:24 > 0:55:25It works for people...
0:55:26 > 0:55:28..and it works for wildlife, too.
0:55:37 > 0:55:41But the knowledge of how delicately it all fits together is fading,
0:55:41 > 0:55:44along with this generation of crofters.
0:55:49 > 0:55:53The high school on Benbecula is addressing this dilemma,
0:55:53 > 0:55:55by offering a special crofting course.
0:55:56 > 0:55:58Students get hands-on experience
0:55:58 > 0:56:01of the fine art of stooking and stacking.
0:56:01 > 0:56:06Up, just keep it tight in together
0:56:06 > 0:56:10so the water's going to shed off one onto the next one.
0:56:10 > 0:56:14Hold on. And what do we call it in Gaelic? You've probably heard it.
0:56:14 > 0:56:16Croitearachd!
0:56:16 > 0:56:18Oh, yeah.
0:56:18 > 0:56:19Start from here.
0:56:21 > 0:56:24It's not just popular, it's oversubscribed.
0:56:30 > 0:56:33It's up to this generation of school-leavers to decide
0:56:33 > 0:56:35whether the machair lives on.
0:56:38 > 0:56:40And these are exactly the people who will be most tempted
0:56:40 > 0:56:45to leave the outer isles for a mainland, mainstream life.
0:56:55 > 0:56:59As summer turns to autumn, the gannets, divers and terns
0:56:59 > 0:57:03will leave these islands, and spread out across the globe.
0:57:11 > 0:57:14Under the cover of darkness, the pufflings will slip out to sea
0:57:14 > 0:57:17to spend many long months on the open ocean.
0:57:22 > 0:57:23But they'll be back.
0:57:25 > 0:57:27Because there's nowhere better than the Hebrides.
0:57:35 > 0:57:40These precious islands on the edge are some of the best places
0:57:40 > 0:57:42for wildlife anywhere in the world.
0:57:53 > 0:57:56Next time, the people of the Hebrides.
0:57:57 > 0:57:59In these islands on the edge,
0:57:59 > 0:58:04wild animals and humans have lived side by side for centuries,
0:58:04 > 0:58:07sharing the same landscape and the same challenges.
0:58:10 > 0:58:12But the world is changing fast...
0:58:14 > 0:58:16..and so are the pressures on people and animals alike.
0:58:21 > 0:58:25Could the people of the Hebrides have found a new way forward,
0:58:25 > 0:58:28through their special relationship with the natural world?
0:58:52 > 0:58:56Subtitles by Red Bee Media Ltd