0:00:44 > 0:00:50Come rain or shine, there really is no more exciting place to be than the British coastline.
0:00:50 > 0:00:55The wind in your hair, the tang of salt air, the endless horizon...
0:00:55 > 0:00:58Oh, it makes you feel glad to be alive,
0:00:58 > 0:01:00close to the forces of nature.
0:01:00 > 0:01:05That's because here, where the land meets the sea, you can feel the power
0:01:05 > 0:01:09of the elements more keenly than anywhere else in the British Isles.
0:01:22 > 0:01:28These elemental forces influence the life of every living thing that makes its home here.
0:01:34 > 0:01:38But they also define the character of the coast itself.
0:01:39 > 0:01:44Just how these primeval forces make our coast the place that we know and love
0:01:44 > 0:01:46is a fascinating story.
0:01:49 > 0:01:53A story that'll take us from one end of our pattern of islands
0:01:53 > 0:01:57to the other, to meet some amazing plants and animals.
0:02:01 > 0:02:07It's an incredible journey to discover the natural wonders of coastal Britain.
0:02:25 > 0:02:27Our journey begins at sea,
0:02:27 > 0:02:30where I'm on the hunt for something rather special.
0:02:38 > 0:02:40Ooh, this'll blow the cobwebs away.
0:02:40 > 0:02:44I'm on a boat in the Sound of Sleet...lovely name...
0:02:44 > 0:02:46off the west coast of Scotland.
0:02:46 > 0:02:49That's the Isle of Skye over there.
0:02:49 > 0:02:53And I've come to look at one of our most magnificent wild animals.
0:02:53 > 0:02:55But where to start?
0:02:55 > 0:02:59The trouble is, up here the ocean all looks much the same.
0:03:00 > 0:03:03Talk about looking for a needle in a haystack...
0:03:06 > 0:03:10But beneath the waves it's a different story...
0:03:10 > 0:03:13all because of the power of the tide.
0:03:14 > 0:03:18The ebb and flow of tidal currents over the seabed
0:03:18 > 0:03:20creates food-rich hotspots
0:03:20 > 0:03:22and these attract fish.
0:03:23 > 0:03:27If I can find one of these tidal hotspots I'm in with a chance.
0:03:29 > 0:03:33There you go. There's a little flurry of birds here, shearwaters.
0:03:33 > 0:03:35They've come for the fish.
0:03:47 > 0:03:48More birds are flying in.
0:03:48 > 0:03:52There are razorbills, guillemots and kittiwakes.
0:03:52 > 0:03:54But they're just the warm-up act.
0:03:54 > 0:03:57There's something much bigger on the way.
0:04:13 > 0:04:14There we are!
0:04:16 > 0:04:19A minke whale! And that's what we've come here to see.
0:04:21 > 0:04:26Wow! That was so close! So close. Look, look there!
0:04:41 > 0:04:44At 30 feet long, these cousins of the blue whale
0:04:44 > 0:04:47really are monsters of the sea.
0:04:59 > 0:05:04With such a whale-sized appetite, the fish don't last long!
0:05:10 > 0:05:12And then they're gone
0:05:12 > 0:05:14and everything's calm again.
0:05:14 > 0:05:20But a real thrill to see them that close too. Just amazing.
0:05:20 > 0:05:24And it just goes to show how, even a long way out at sea,
0:05:24 > 0:05:28the power of the tide affects the lives of our coastal wildlife.
0:05:30 > 0:05:35In fact, Britain has some of the biggest tides in the world.
0:05:40 > 0:05:44Twice a day they completely transform our coastline,
0:05:44 > 0:05:46making it really tough for anything
0:05:46 > 0:05:50living in the no-man's-land between high and low water.
0:05:56 > 0:06:00And there's no better place to see that than here.
0:06:10 > 0:06:14This extraordinary, almost extra-terrestrial landscape
0:06:14 > 0:06:16is on the south coast of Jersey,
0:06:16 > 0:06:20and it has one of the largest tidal ranges in the world
0:06:20 > 0:06:22at fully 12 metres, that's 40 feet,
0:06:22 > 0:06:25between the highest and the lowest tides.
0:06:25 > 0:06:30When the tide goes out here the island almost triples in size,
0:06:30 > 0:06:34and it reveals an environment so harsh and so challenging
0:06:34 > 0:06:37that it almost looks like another planet.
0:06:39 > 0:06:43Under the blazing sun, these rocks roast
0:06:43 > 0:06:45and rockpools shrink.
0:06:51 > 0:06:55With all that to contend with you might think that nothing could live on the seashore.
0:06:55 > 0:06:58But there are actually millions of living things here
0:06:58 > 0:07:02in getting on for a thousand different species.
0:07:02 > 0:07:04It's just that they're all hiding.
0:07:04 > 0:07:07But if you look more closely you'll find creatures
0:07:07 > 0:07:12every bit as bizarre as the alien environment in which they live.
0:07:12 > 0:07:15OK, it's a crab...
0:07:15 > 0:07:19But have you ever thought just how odd they really are,
0:07:19 > 0:07:24with their armour-plated shells, eight legs and sideways walk?
0:07:24 > 0:07:27And some creatures are even more bizarre.
0:07:27 > 0:07:29The bootlace worm.
0:07:29 > 0:07:35At 30 metres, one of the longest creatures on earth, and more elastic
0:07:35 > 0:07:38than elastic.
0:07:39 > 0:07:44They really could be the cast of a sci-fi special!
0:07:59 > 0:08:00Here are two beauties.
0:08:00 > 0:08:03The squat lobster, which doesn't grow
0:08:03 > 0:08:05any more than three inches long.
0:08:05 > 0:08:08It can hide in the tiniest of rocky crevices.
0:08:08 > 0:08:10And here, the clingfish,
0:08:10 > 0:08:14whose two pelvic fins are fused to form a kind of sucker
0:08:14 > 0:08:18so that it can stick itself to the rock when the tide beats against it,
0:08:18 > 0:08:20and that way it won't fall off.
0:08:22 > 0:08:24Just like that!
0:08:27 > 0:08:32The question that pops into your mind, though, is if this is such a challenging place to live,
0:08:32 > 0:08:37and you have to spend half your day hiding under a rock, why is so much living here?
0:08:40 > 0:08:45It's all about balance between the good times and the bad times.
0:08:45 > 0:08:49If you're tough enough to survive when the tide's out...
0:08:52 > 0:08:57..then there's a very big payoff when it comes back in.
0:09:04 > 0:09:09With the returning tide comes a whole load of food!
0:09:23 > 0:09:27What seemed a barren wasteland now bursts with life!
0:09:50 > 0:09:56For other seaside creatures, though, it's not just the tide that influences their lifestyle
0:09:56 > 0:09:59but something we probably take for granted.
0:10:00 > 0:10:03The cycle of night and day.
0:10:12 > 0:10:15Long after we've packed up our deckchairs
0:10:15 > 0:10:17and are tucked up in bed...
0:10:19 > 0:10:22..shadowy figures emerge at the tideline,
0:10:22 > 0:10:25in search of a midnight feast.
0:10:27 > 0:10:29SNUFFLING
0:10:38 > 0:10:40The sand itself seems to come alive
0:10:40 > 0:10:44as tiny sandhoppers emerge into the cool night.
0:10:47 > 0:10:51But these scavengers must beware.
0:10:51 > 0:10:54CROAKING
0:11:01 > 0:11:06Toads! Sharpshooters of this night-time world.
0:11:08 > 0:11:12They breed in freshwater pools behind the dunes,
0:11:12 > 0:11:16and come the night they mosey on down to the beach.
0:11:28 > 0:11:32With excellent night vision... and the fastest tongue in the west,
0:11:32 > 0:11:35they ambush anything that moves.
0:11:40 > 0:11:44And on the tideline dinner is, quite simply,
0:11:44 > 0:11:46popping up all over the place!
0:12:08 > 0:12:11But there's always one slippery little customer.
0:12:15 > 0:12:18Toads tend to be nocturnal wherever they live,
0:12:18 > 0:12:22but there are some creatures of the night who,
0:12:22 > 0:12:25when they live on the coast, become creatures of the day.
0:12:32 > 0:12:36To find them, I'm heading right to the far north of the country.
0:12:55 > 0:12:57Shetland has more than its fair share of coastline,
0:12:57 > 0:13:02900 miles in all, composed of rocky crags and little inlets.
0:13:02 > 0:13:06If you wanted to walk all round it, it would take you weeks and weeks.
0:13:06 > 0:13:11It's washed by the cold waters of the Atlantic and the North Sea,
0:13:11 > 0:13:15creating this bleak but beautiful landscape
0:13:15 > 0:13:18and yet it's home to one of Britain's most elusive animals.
0:13:18 > 0:13:20Elsewhere you'd seldom see it by day
0:13:20 > 0:13:25and even here you've got to have a keen eye and bags of patience.
0:13:34 > 0:13:39It's one of the few creatures that's as happy on land as it is in water.
0:13:46 > 0:13:49And there it is. An otter!
0:13:49 > 0:13:51A mother with her cub.
0:13:53 > 0:13:57The story is that they came here introduced by the Vikings
0:13:57 > 0:13:59and they've lasted ever since,
0:13:59 > 0:14:03so they've got pretty good squatters' rights, I'd have thought.
0:14:08 > 0:14:10They're on the move.
0:14:10 > 0:14:13Don't suppose they get many days like this to sunbathe.
0:14:17 > 0:14:22After you've sunbathed, well, you fancy a swim, don't you?
0:15:03 > 0:15:07It's a great treat to get within 100 yards of two otters
0:15:07 > 0:15:09who don't know you're there.
0:15:09 > 0:15:12Forget your big game in Africa,
0:15:12 > 0:15:14this will do me nicely!
0:15:21 > 0:15:25Otters like to catch their prey by surprise.
0:15:46 > 0:15:49Inland, where otters live on rivers,
0:15:49 > 0:15:53they tend to hunt at night, when the fish they eat are sleeping.
0:15:54 > 0:15:59But here, on the coast, some fish rest during the day,
0:15:59 > 0:16:03so otters are out and about hunting during daylight hours.
0:16:12 > 0:16:16We've always had a love affair with the otter.
0:16:16 > 0:16:19Whether or not it's because it's such a beautiful animal
0:16:19 > 0:16:22or because it has such an expressive face, I don't know.
0:16:22 > 0:16:26But the good news is that otters are becoming more common
0:16:26 > 0:16:27throughout mainland Britain.
0:16:27 > 0:16:32So perhaps sights like this will become more frequent.
0:16:32 > 0:16:34But, from my point of view,
0:16:34 > 0:16:36it can't be more special.
0:16:48 > 0:16:52Between them the sun and the moon
0:16:52 > 0:16:54drive the rhythm of life along the coast,
0:16:54 > 0:16:57whether it's the cycle of night and day
0:16:57 > 0:17:00or the rising and falling of the tide.
0:17:00 > 0:17:05But the sun has another, and even more important role to play,
0:17:05 > 0:17:09and the evidence for that is about to emerge all around me.
0:17:41 > 0:17:44The sun's energy is the fuel of life
0:17:44 > 0:17:47on our coast just as in the rest of Britain.
0:17:47 > 0:17:51And it's plants that harness that energy.
0:18:04 > 0:18:07The result in the month of May
0:18:07 > 0:18:10is a clifftop that's as bright as any garden.
0:18:10 > 0:18:15Sheets and sheets of bright yellow birdsfoot trefoil and horseshoe vetch,
0:18:15 > 0:18:21perforated with the delicate white flowers of the sea campion.
0:18:21 > 0:18:26And then clump after clump of sea pinks, also known as thrift.
0:18:26 > 0:18:28It used to be on the back of the old threepenny bit.
0:18:28 > 0:18:34Called thrift I think because it can make do with very, very little soil in the crevices among these rocks.
0:18:34 > 0:18:37It's a sight that'll gladden anybody's heart,
0:18:37 > 0:18:41but all these plants and flowers are also vital for wildlife.
0:18:44 > 0:18:48Having captured the sun's energy, they pass it on to insects...
0:18:51 > 0:18:55..and insects pass it on to birds.
0:18:55 > 0:18:57As any schoolboy knows,
0:18:57 > 0:19:00it's a classic food chain.
0:19:03 > 0:19:06And though we can't see it as clearly
0:19:06 > 0:19:09exactly the same process is happening underwater.
0:19:11 > 0:19:14Seaweeds aren't plants in the true sense of the word,
0:19:14 > 0:19:19but they harness the sun's energy in much the same way.
0:19:19 > 0:19:22Look at this lot over here.
0:19:25 > 0:19:29Instead of roots they've got a holdfast which enables them
0:19:29 > 0:19:31to cling on to the rocks
0:19:31 > 0:19:35and then the foliage floats ever upwards towards the sun,
0:19:35 > 0:19:37held by these gas-filled bladders.
0:19:54 > 0:19:58We have over 800 different kinds of seaweed
0:19:58 > 0:20:00in such varied shapes and colours
0:20:00 > 0:20:04that they can be as beautiful as any garden on land.
0:20:11 > 0:20:14But even seaweeds aren't the most important part
0:20:14 > 0:20:16of this underwater food chain.
0:20:16 > 0:20:20That distinction belongs to another group of sun lovers
0:20:20 > 0:20:24that are far stranger and much harder to spot than seaweed.
0:20:28 > 0:20:32These tiny green jewels are phytoplankton
0:20:32 > 0:20:35and there are billions of them in our oceans.
0:20:41 > 0:20:44Feeding on them, rather like cows grazing on grass,
0:20:44 > 0:20:49is a whole array of microscopic animals called zooplankton.
0:20:51 > 0:20:53Together they form the basis of a food chain
0:20:53 > 0:20:56which has Britain's coastal waters
0:20:56 > 0:20:59teeming with an incredibly rich variety of life.
0:22:01 > 0:22:06Weighing in at 300 kilograms, you might think that the grey seal
0:22:06 > 0:22:09is top of Britain's underwater food chain.
0:22:09 > 0:22:13But occasionally, just off the coast of Scotland,
0:22:13 > 0:22:16they're dwarfed by a much larger and more famous predator.
0:22:23 > 0:22:27These are the true lords of our seas.
0:22:30 > 0:22:31And they're hungry.
0:22:34 > 0:22:38The grey seals are a favourite prey.
0:22:46 > 0:22:49Killer whales are on the prowl.
0:23:00 > 0:23:02HONKING
0:23:28 > 0:23:32As the seals head for the rocks and safety,
0:23:32 > 0:23:35the whales try to block their escape.
0:23:54 > 0:23:59Choosing a victim, they work together to close the net.
0:24:44 > 0:24:48It's an astonishing spectacle, and who'd have thought you could
0:24:48 > 0:24:53watch killer whales hunting right next to the British coast?
0:25:01 > 0:25:05And there are other creatures in our coastal waters
0:25:05 > 0:25:06just as extraordinary,
0:25:06 > 0:25:11but to see them you have to go a long, long way out to sea.
0:25:11 > 0:25:16Funnily enough, to a place where the sun doesn't shine.
0:25:18 > 0:25:23I'm heading out northeast from Aberdeen on the northeast coast of Scotland,
0:25:23 > 0:25:26for about a hundred miles, out into the open ocean.
0:25:26 > 0:25:30But these seas are still an important part
0:25:30 > 0:25:32of our natural British environment.
0:25:32 > 0:25:38We're, if you like, responsible for them and yet we know so little of what they contain.
0:25:41 > 0:25:44Now, somewhere here there's a landing site.
0:25:48 > 0:25:52There she is! Transocean Sedco 712.
0:25:54 > 0:25:56And am I pleased to get here!
0:25:58 > 0:26:03An oil rig is an amazing feat of human ingenuity and engineering.
0:26:03 > 0:26:06Some of the technology used here has given us an insight
0:26:06 > 0:26:11into parts of the natural world that we would otherwise never have seen.
0:26:11 > 0:26:18To keep an eye on the well-head and the pipework hundreds of feet below, the rig uses an ROV,
0:26:18 > 0:26:22a remotely operated vehicle. It's this yellow thing here.
0:26:22 > 0:26:26It's basically a miniature submarine armed with lights and cameras
0:26:26 > 0:26:31and it's what those cameras can see that I've come here to look at today.
0:26:31 > 0:26:34I'll get a better view from the control room.
0:26:39 > 0:26:44We're about 200 feet down now, nothing much at the moment except bubbles.
0:26:44 > 0:26:48Probably going too fast to see much at the moment, aren't we?
0:26:48 > 0:26:50Zooming past life.
0:26:50 > 0:26:52Yeah, it's a bit murky as well.
0:26:52 > 0:26:54Yes, this is the North Sea, not the Caribbean.
0:26:54 > 0:26:58Exciting, this, cos you just don't know what you're going to find.
0:26:58 > 0:27:02OK, that's us stopped just there. Secure the winch, please.
0:27:02 > 0:27:05It's just like space exploration in its way, isn't it?
0:27:08 > 0:27:11Is it my imagination or is something coming out of the gloom?
0:27:11 > 0:27:13Something's coming out of the gloom!
0:27:15 > 0:27:19What this camera and others like it around the North Sea have picked up
0:27:19 > 0:27:22are some quite extraordinary images
0:27:22 > 0:27:25of creatures living in the murky depths.
0:27:55 > 0:27:59It's a privileged view of some alien-looking beings
0:27:59 > 0:28:01few people have ever seen,
0:28:01 > 0:28:04but they're all part of our British wildlife.
0:28:19 > 0:28:24Back on terra firma, this is more like the seaside I love,
0:28:24 > 0:28:26and you just can't beat it!
0:28:28 > 0:28:33We Brits are drawn to it like magnets to soak up some rays,
0:28:33 > 0:28:37take a swim, generally relax and recharge.
0:28:40 > 0:28:42But beneath this holiday resort
0:28:42 > 0:28:47is something created by another, vital force of nature.
0:28:47 > 0:28:50This is Southport in Merseyside,
0:28:50 > 0:28:53one of Britain's first coastal resorts.
0:28:53 > 0:28:57People have been flocking here in their millions since the end of the 18th century,
0:28:57 > 0:29:01and I bet you anything quite a few of them complain about the wind.
0:29:01 > 0:29:04But if it weren't for wind Southport wouldn't exist.
0:29:04 > 0:29:10You see, this is all built on sand dunes, and sand dunes are formed... by wind.
0:29:18 > 0:29:20And, boy, is there a lot of it!
0:29:20 > 0:29:25To build really good dunes you need a gently shelving shore,
0:29:25 > 0:29:29acres of sand and of course lots of wind.
0:29:32 > 0:29:37It's once the sand's dried out that the wind can really get to work.
0:29:39 > 0:29:44At a critical speed it starts to carry the sand up the beach
0:29:44 > 0:29:48and it does so by a fascinating process.
0:29:50 > 0:29:53It's happening here, right now.
0:29:53 > 0:29:58The wind picks up a single grain of sand, carries it for a few feet,
0:29:58 > 0:30:00then, as it drops onto the beach,
0:30:00 > 0:30:03so it dislodges several more grains of sand.
0:30:03 > 0:30:07They fly up and as they land they dislodge even more,
0:30:07 > 0:30:10starting this enormous chain reaction, until,
0:30:10 > 0:30:14as you can see, the entire beach is on the move.
0:30:14 > 0:30:19And it will continue to move until it hits a stationary object,
0:30:19 > 0:30:22and when that happens it starts to build up
0:30:22 > 0:30:25and it turns into a sand dune.
0:30:32 > 0:30:36But the wind can't build a full-size sand dune alone.
0:30:36 > 0:30:40It works in partnership with some highly specialised plants.
0:30:40 > 0:30:45First into the fray is this one, sea rocket.
0:30:45 > 0:30:47It's fast growing. It has to be here.
0:30:47 > 0:30:52It's tolerant of saltwater, even its seeds can float, but it's not
0:30:52 > 0:30:56terribly tall-growing, which means that the little dunes around this
0:30:56 > 0:30:58can only make it to about a foot.
0:30:58 > 0:31:01To get that little bit higher, they need a plant that's capable
0:31:01 > 0:31:04of growing taller and which has a dense root system.
0:31:04 > 0:31:07And that's this. Couch grass.
0:31:07 > 0:31:11Now the dunes are what they call embryo dunes,
0:31:11 > 0:31:13growing five feet high.
0:31:13 > 0:31:15But they can get bigger.
0:31:15 > 0:31:18And for that they need the help of one more plant.
0:31:18 > 0:31:22And this is it - marram grass!
0:31:22 > 0:31:26Capable of surviving in the teeth of a maritime gale.
0:31:26 > 0:31:30Its roots go down for several yards, and its top growth
0:31:30 > 0:31:35is capable of piercing 3ft of sand dumped on top of it.
0:31:35 > 0:31:37Try doing that to your back lawn.
0:31:37 > 0:31:40These dunes can last for decades.
0:31:40 > 0:31:45Gradually they become more stable, ultimately creating new land.
0:31:48 > 0:31:50And new life moves in.
0:31:54 > 0:31:58Arctic terns fly all the way from Antarctica
0:31:58 > 0:32:00to nest in our sand dunes.
0:32:13 > 0:32:18Making their nests on the ground, they use these dune grasses
0:32:18 > 0:32:22to hide their young chicks from the prying eyes of gulls and foxes.
0:33:12 > 0:33:17But if you're tiny, living in these windswept dunes isn't so easy.
0:33:18 > 0:33:21Some bees lead solitary lives
0:33:21 > 0:33:26and the females build nests in small holes in wood or rocks.
0:33:26 > 0:33:30But here on these dunes both are in short supply.
0:33:32 > 0:33:37So one species of bee has come up with an ingenious solution.
0:33:37 > 0:33:42Scattered all around are hundreds of empty snail shells...
0:33:44 > 0:33:50..and for a female snail bee they make the perfect seaside home.
0:33:52 > 0:33:56After selecting a shell she gathers nesting material,
0:33:56 > 0:33:58rather like a bird.
0:33:58 > 0:34:02She chews up bits of leaf to make a soft pulp,
0:34:02 > 0:34:06then uses this to line the inside of the shell.
0:34:16 > 0:34:19Then she collects pollen and nectar
0:34:19 > 0:34:23to provide food for her larvae when they hatch.
0:34:34 > 0:34:38After laying her eggs she seals the shell
0:34:38 > 0:34:42and flies off to begin all over again.
0:34:42 > 0:34:44This clever little bee
0:34:44 > 0:34:48can nest in as many as five different shells in a season.
0:34:48 > 0:34:51She gets my vote for the busiest bee in Britain!
0:35:03 > 0:35:05Wind and sand give us sand dunes,
0:35:05 > 0:35:08creating new land along our coastline,
0:35:08 > 0:35:10but wind and water combine to make
0:35:10 > 0:35:14a completely different coastal feature.
0:35:15 > 0:35:17Waves!
0:35:28 > 0:35:32Waves are made as wind ripples the surface of the ocean.
0:35:35 > 0:35:37The really big ones we get
0:35:37 > 0:35:41have swept across the Atlantic growing up to 30 feet high.
0:35:41 > 0:35:44And it's the coasts of southwest Britain
0:35:44 > 0:35:47that feel their greatest force.
0:35:58 > 0:36:02They make the coves, the headlands and the caves
0:36:02 > 0:36:04for which this coastline is famous.
0:36:07 > 0:36:08SHRIEK
0:36:08 > 0:36:13There are salty tales of the sea from times gone by that tell
0:36:13 > 0:36:19of sailors being lured toward the rocks by the calls of mermaids,
0:36:19 > 0:36:22beckoning them to an early grave.
0:36:22 > 0:36:25The mermaids may have been imagined,
0:36:25 > 0:36:28but those sounds most certainly were not.
0:36:38 > 0:36:43This looks like a passageway to the centre of the Earth,
0:36:43 > 0:36:49it was carved out by thousands of years of wave activity.
0:36:50 > 0:36:53You do get the distinct feeling...
0:36:55 > 0:36:56..that you're being watched.
0:37:01 > 0:37:03MOANING
0:37:03 > 0:37:06The deeper you get into the cave,
0:37:06 > 0:37:09the more that strange sound...
0:37:09 > 0:37:11gets closer.
0:37:22 > 0:37:23And there it is.
0:37:26 > 0:37:29It's not a mermaid at all.
0:37:29 > 0:37:32It's a baby grey seal.
0:37:32 > 0:37:35Perhaps just two or three days old, no more.
0:37:35 > 0:37:40And its mother's left it in the safety of the cave while she goes off to feed.
0:37:41 > 0:37:47She suckles it for about 18 days. Insatiable appetite, those.
0:37:47 > 0:37:50During which time its body weight increases dramatically.
0:37:50 > 0:37:56After that time she pushes off and it's left to fend for itself.
0:37:56 > 0:37:58It really is a case of sink or swim.
0:37:58 > 0:38:00Amazing sight!
0:38:02 > 0:38:04Good luck.
0:38:04 > 0:38:06Time we left it alone, I think.
0:38:19 > 0:38:23One way or another, wave power has a big influence
0:38:23 > 0:38:26in shaping the lives of coastal wildlife,
0:38:26 > 0:38:31but this destructive power isn't just making caves,
0:38:31 > 0:38:34it's constantly re-sculpting our coastline,
0:38:34 > 0:38:38creating many of our best known landmarks.
0:38:38 > 0:38:41From the chalk cliffs of Dover
0:38:41 > 0:38:43to the towering granite crags of Scotland,
0:38:43 > 0:38:48you'll see a landscape carved by the power of wind and waves.
0:39:06 > 0:39:10And these cliffs give us something else for which the British coastline
0:39:10 > 0:39:12is justly famous.
0:39:24 > 0:39:28Millions of nesting seabirds.
0:39:40 > 0:39:44Stac Lee is on St Kilda in Scotland's Outer Hebrides,
0:39:44 > 0:39:48the remotest part of the British Isles.
0:39:53 > 0:39:55For a few months in summer,
0:39:55 > 0:40:00Britain is home to the largest colony of gannets in the world.
0:40:00 > 0:40:03BIRDS SQUAWKING
0:40:19 > 0:40:23For them, our cliffs make the perfect home.
0:40:26 > 0:40:29Up here they are safe from predators.
0:40:29 > 0:40:34And right on their doorstep is miles and miles of water packed with food.
0:40:36 > 0:40:40Because deep-sea fishing is just what these birds are designed for.
0:40:42 > 0:40:46From way up in the sky, they lock in on their underwater prey.
0:40:49 > 0:40:53Then, like living torpedoes, they slam into the water
0:40:53 > 0:40:56at speeds of around 75 miles an hour.
0:41:54 > 0:41:56Soon they'll head back out to sea,
0:41:56 > 0:41:59and the sound of nesting gannets on these cliffs
0:41:59 > 0:42:01will be a distant memory.
0:42:01 > 0:42:03At least, until next year.
0:42:10 > 0:42:16If you had to choose just one place that summed up the elemental nature of Britain's coastline,
0:42:16 > 0:42:21then this estuary at Snettisham on the Norfolk coast would be a pretty strong contender.
0:42:21 > 0:42:24The deadly power of the tide is never far away,
0:42:24 > 0:42:26and in this huge open space
0:42:26 > 0:42:32there's no hiding place from the sun, the wind and the waves.
0:42:32 > 0:42:40And yet this place owes it existence not to these, but to the last of our forces of nature, the rain.
0:42:43 > 0:42:47But it's not the rain falling on the coast that matters,
0:42:47 > 0:42:50it's the rain falling much further inland.
0:43:03 > 0:43:07The fresh water that rain brings to the British Isles
0:43:07 > 0:43:09is absolutely vital.
0:43:21 > 0:43:27All across the countryside, rain drains into streams,
0:43:27 > 0:43:31streams into small rivers
0:43:31 > 0:43:34and small rivers into big rivers.
0:43:50 > 0:43:55And it's in estuaries, where rivers meet the sea,
0:43:55 > 0:43:57that most of the rains end up.
0:44:13 > 0:44:16And they bring with them this.
0:44:19 > 0:44:24Mud. An accumulation of huge quantities of soil and silt
0:44:24 > 0:44:26washed downriver by rainwater.
0:44:26 > 0:44:31And it might not look very pretty but it's packed full of food,
0:44:31 > 0:44:36and that makes our estuaries one of the most fertile places on earth.
0:44:36 > 0:44:39But if this is so full of food...
0:44:39 > 0:44:41why's it so empty?
0:44:43 > 0:44:48Well, much of the life here lives in, rather than on, the mud.
0:44:50 > 0:44:51If you dig down,
0:44:51 > 0:44:56you'll find it chock-full of highly specialised creatures.
0:44:57 > 0:44:59Mudshrimp...
0:45:00 > 0:45:03..and ragworms...
0:45:04 > 0:45:07..and billions of tiny snails.
0:45:07 > 0:45:11Because these specialists can tolerate the mix
0:45:11 > 0:45:13of freshwater and seawater,
0:45:13 > 0:45:15they have the mud all to themselves.
0:45:17 > 0:45:20Except when the tide's out.
0:45:21 > 0:45:27There are some hunters that come specially equipped to winkle their prey from the mud.
0:45:27 > 0:45:32At first glance you can't see anything at all, but then, with a pair of binoculars,
0:45:32 > 0:45:35when you get your eye in, you can see them,
0:45:35 > 0:45:39rather like wildebeest scattered across the Serengeti,
0:45:39 > 0:45:44thousands and thousands of birds.
0:45:46 > 0:45:50In fact, millions of birds come to over-winter in our estuaries,
0:45:50 > 0:45:54and for them this mud is a gastronomic treat.
0:45:55 > 0:45:58There are bills of all shapes and sizes
0:45:58 > 0:46:01to probe beneath the mud.
0:46:03 > 0:46:05The curlew's is long and curved
0:46:05 > 0:46:09and sinks deep into the burrows of lugworms.
0:46:14 > 0:46:18The redshank's have sensitive nerve endings
0:46:18 > 0:46:21to pick up minute vibrations below the surface.
0:46:25 > 0:46:28While the heavy dagger-like beak of the oyster catcher
0:46:28 > 0:46:31is perfect for spearing ragworms.
0:46:35 > 0:46:39They all feed as quickly as they can, because it's not long
0:46:39 > 0:46:41before the tide turns once more.
0:47:00 > 0:47:02As it covers their feeding grounds,
0:47:02 > 0:47:05the birds are forced closer and closer to land,
0:47:05 > 0:47:11finding safety in numbers as they wait for the tide to retreat again.
0:47:21 > 0:47:23Funny really, isn't it,
0:47:23 > 0:47:28that when you come to the coast, all you really want is sunshine,
0:47:28 > 0:47:30and yet it's the wind, the rain,
0:47:30 > 0:47:35the tide and the sun all working together that actually make it
0:47:35 > 0:47:37a place worth visiting
0:47:37 > 0:47:41and one of the richest and most rewarding landscapes
0:47:41 > 0:47:43of the British Isles.
0:48:45 > 0:48:50Subtitles by Red Bee Media Ltd