Scotland's Western Isles Coast

There are hundreds of islands along Scotland's West Coast,

each one its own little world,

connected to the neighbours by a great highway, the Atlantic Ocean.

On Skye, Alice Roberts discovers a remarkable use for seaweed.

This is brown gold.

Newcomer to Coast, Kate Rew,

is on the hunt for a tiny creature that eats whalebones.

It is what some people call the bone-eating snot flower!

And Nick Crane attempts to measure the length of the very wiggly British coastline.

91, 92...

Are you on the home straight now?

I'm concentrating! 94...

The waters of the Inner Hebrides are teeming with wildlife,

from the smallest to the biggest creatures.

Whales roam these seas close to the islands.

Tobermory is the embarkation point for many a whale-watching trip...

but wild swimmer Kate Rew is hitching a ride on an expedition like no other.

I've always loved the idea

that I might be swimming close to a whale in open water,

and I'm keen to find out more about their remarkable lives,

so it's wonderful to be here to join this expedition,

to explore one of their mysterious secrets - what happens to whales when they die?

Whales of all shapes and sizes swim between the islands off the West Coast of Scotland.

These waters are a whale's super-highway - a migration route spanning the world's oceans.

They're out there all right, just not that easy to spot.

Very nice to meet you!

Very nice to meet you too.

-But today, I'm meeting marine biologists Adrian Glover and Kim Last.

-Welcome on board.

Thank you very much. They know where one whale is, or part of it anyway.

We're heading 15 miles out to sea to recover some whalebones

they placed on the seabed 15 months ago,

part of an extraordinary experiment.

It's something which is very new, really just in the last few years,

we've started to understand what animals would eat a whale,

and, in particular,

whale bones, which is really what this experiment is all about.

When whales die, they fall to the bottom of the ocean,

becoming a hearty meal for sea life

that strips the flesh from the bones.

Once the flesh is completely eaten,

you'd think the story would all be over, but it's not.

The whale skeleton also provides a whole host of animals

with a rich source of food.

And it's one of these bone-eating creatures that Adrian is particularly interested in.

We're hoping to find some of these strange animals that we call Osedax.

We have a picture of one here, dissected out of a whalebone,

it is what some people call the "bone-eating snot-flower", most peculiar name!

I've got to say, it's beautiful-looking.

When you told me we were looking for a bone-eating snot-flower,

I wasn't expecting anything as pretty as this!

Yeah, I think maybe we gave it the wrong name!

It is a bit of a misnomer.

It's actually a worm, it's a polychaete worm,

it's highly adapted to living on this weird environment.

So these flowers that you see, the red flowers, are actually there to get oxygen

into this weird structure you see at the base,

which is actually a root which is inside the whalebone.

Would we actually see any of these with the naked eye, are we going to be seeing some?

They stick out a centimetre or so out of the whalebone.

What perplexes scientists is how the tiny bone-eating snot-flowers

travel the ocean seeking whalebones to feed on.

Adrian has a theory that they hop from whalebone to whalebone.

If these things are concentrated along certain areas,

they can use them as sort of stepping-stones in the deep.

So putting down this experiment, even though it's really quite a small experiment

that we're looking at today,

is really important in looking at the whole dispersal of deep sea organisms.

For over a year, 50 metres down in the cold dark Atlantic,

the whalebone has been waiting.

The team are hoping exotic bone-eating creatures have moved in,

only now will the scientists find out if it's all been worth it.

But there's a problem.

The whalebone should be attached to a large mooring buoy, but it's nowhere to be seen.

No buoy means no bone, over a year's work could be lost.

We've had a lot of storms or maybe a trawler has come through

and picked it up and dragged it away.

So we're a little bit on tenterhooks at the moment.

Working at sea is very unpredictable.

Their only hope is to spot the much smaller back-up buoy or pellet.

But there's little hope of seeing it until the tide turns.

What happens is the current actually drags them under water,

so they may just pop up when the tide goes slack.

After a nail-biting wait, the pellet finally reveals itself.

Our bone might still be recovered.

Whenever you bring up something from the deep ocean, you always find

interesting things, so we're guaranteed interesting things.

I think that's one of the exciting things about this site, you never know what you're going to get.

It's there, it's there, it's there! That's it! There's the bone.

-Oh, my God!

-They haven't fallen off.

They haven't fallen off!

There's one large vertebra and we've got a few smaller ones.

A minke whale next to it, you can see.

-That's right.

-So it's like a sweet assortment, but for whales?

-That's right!

Kim and Adrian are quick off the mark to get to their bone,

and they certainly seem excited about something.

We've got bacterial bracts, that's the white stuff there.

We've got gastropods, we've got sea slugs, we've got molluscs...

-Have you found any snot-flowers?

-No snot-flowers yet.

We've found quite a few interesting animals though.

This is something that we've been picking out.

Oh, wow! Look at that, it's like a mini lobster.

Squat lobsters.

We have sea urchins...

-You're missing out this guy! What's this strange creature?

-This is a spider crab.

All these animals are things that live on hard subspace,

hard things in marine environment.

So we've got quite a lot of organisms here,

able to use the whalebone as if it was kind of a reef, really.

I mean, no-one's done this experiment, so no-one knows.

So whatever we get is interesting.

Even though I haven't seen any bone-eating snot-flowers today,

my eyes have been opened to a new world,

that something as barren-looking as a whale skeleton

is actually an island home to a whole community of extraordinary creatures.

Just off our coast, deep on the seabed,

there's a delicate eco-system at work that we know so little about.

On their restless journey through the oceans, whales navigate their way past these islands.

But I can't resist a stop at Canna.

I'm always captivated by these clumps of rock and grass that seem to defy the surrounding sea.

Each of these islands is unique, its own little world,

a miniature eco-system where people, plants and animals

have to learn to live together.

But things haven't always gone smoothly.

The sea eagles which used to soar high above these cliffs were hunted to extinction.

By 1918, there wasn't a sea eagle to be seen on Canna.

Since then, many people have left too.

There's only about 20 full-time residents now, but the sea eagles have been brought back.

It's Abbie Patterson's job to watch over them.

Canna is a good place because it's a very wild and remote island,

there's plenty of food here,

plenty of rabbits for the eagles to actually feed on.

So... and it's also a place that isn't disturbed very much,

very few people come to this corner of the island,

so the birds are left alone, and that's really what they need, no disturbance and plenty of food.

The sea eagles may feel at home on Canna,

but they had to be re-introduced from Norway.

Back in 1975, RSPB volunteers were scaling Norway's mountains.

As the eagles were doing well there, it was safe to remove a number of the enormous chicks.

The chicks were then flown to Scotland and released on the island of Rumm, right next to Canna.

At that time, no-one could have anticipated how successful the re-introduction was going to be.

Overall in Scotland there's probably about 200 at this present time.

And how many of those are on Canna?

Well, we have two pair here,

they've been here since probably the late '80s

and probably came from Rumm and moved across to Canna.

They've been fairly successful since then,

one pair better than the other pair, as you always get.

And is there anywhere here that we can see signs of Sea Eagles today?

Yes, there is. Just on the cliff up behind me we should hopefully see some signs anyway.

Cliff...that sounds ominous!

In this exposed terrain, finding any sign of the Sea Eagles isn't easy.

We're going to check a recently vacated nest to see if they're eating well enough to survive.

What I hadn't bargained on was the nest being halfway up this cliff!

You do a lot of this, do you?

Occasionally, not too much these days, but in the old days I did quite a lot.

-You know I've never done this before, don't you?

-Aye, I know.

I'd like you to know that I'm quite liking it,

but mostly I'm hating it!

This is not the best fun I've ever had, let me assure you!

Oh, I'm here! I'm here!

I'm so pleased. Right, jolly good.

I have to say that at first sight,

this does not look like a bird's nest as such to me.

Is this standard issue? Just a flattened platform of debris?

This is it, yes.

It's... Quite often, it's built up at the beginning of the season and looks a lot better.

You know, there's a lot of sticks and seaweed and various other things.

And then it lines it a little bit with heather and various things like that.

By the end of the season, of course, the birds have been here for several months,

so by the time they're finished with this, it's as you see it now.

What is that? It's a jawbone.

This is a jawbone yes. It's not human, I can say, but what this is, it's herbivore.

-And that's a small lamb.

-It's a lamb? Right.

-A small lamb.

Cos that is the kind of prey, in your mind's eye,

-that's what I think about something like a sea eagle taking.

-Yes, that's right.

There's a tendency that obviously the sea eagles are not liked by shepherds etc,

because they are taking lamb.

And in some of these areas, financial schemes have been set up to try and offset some of these costs.

But here on Canna, looking at the actual dietary requirements of the eagle,

there's only something like 0.2% of lamb amongst everything that it eats.

Now, that's not a large amount.

We know from the nest that the eagles are feeding well enough,

which promises well for their future,

but still no sign of the birds until...finally.

It's iconic, isn't it, seeing it against the colour of the sky?

-Absolutely.

-What a backdrop.

You couldn't get a finer backdrop.

It's going to come right past us!

Just to be sitting on a day's visit, to catch a sight like that is fantastic.

So just how big is that bird that we're looking at?

Well, it's the largest bird of prey that we've got in the UK,

and that's an 8ft wingspan approximately, so that is huge.

It's often described as a flying barn door!

Well, it's about the size of a door in somebody's house, isn't it?!

It's really big. But it's also very broad, a very, very broad wing.

So they're absolutely massive birds and there's different sizes between male and female.

You find a female is a much bigger bird than the male.

-That was amazing.

-That was great.

I didn't think we'd see anything!

Well, I was a little bit dubious myself, but I'm really happy that it's come by for us.

The bridge reaching out to one of Scotland's most famous islands has only been here since 1995.

It's just a thin ribbon of road, but it's a permanent connection to the mainland.

It begs the question - is Skye an island any more?

Members of the local community own and run a ferry

further down the coast for those who prefer going over the sea to Skye.

Alice Roberts is one of them.

Well, the boats have changed over the years,

but this journey still connects back to the

age-old tradition of the isles, when everything - people, goods, animals -

had to come across on the water.

I'm meeting Donald John McLeod,

who brought the mail across this narrow stretch of water for 50 years.

He's witnessed first-hand how Skye has changed since the arrival of the bridge.

When an island is connected by a causeway or a bridge,

the island changes.

An island community, they're dependant on each other.

But now you can get off it 24/7,

go to wherever in the world.

And you used to bring the mail over to Skye?

Yes, I did. Up to the Second World War, very few houses had telephones,

so everything came by mail.

-So it sounds that your boat was a bit of a lifeline for people?

-Oh, yes, it was. At that time,

absolute lifeline, yes.

And how important are boats now, do you think?

Tourist attractions!

This stretch of water wasn't just a lifeline for communication,

it was once essential for industry too.

Running any kind of enterprise on the isles used to rely on sea trade,

and 200 years ago, the business on the boats was booming.

The island looks so unspoilt.

Hard to believe that the smog of pollution once hung over these shores,

and that an entire industry was born and died here,

all based on the stuff under my feet.

This is brown gold, seaweed.

And as strange as it seems, there are chemicals in this

that 200 years ago were crucial to the glass-making industry.

To make glass, you need soda ash.

Until the late 1700s, Britain's main source for that was Spain.

But then came war with Napoleon, and all imports stopped,

shattering news for the glass industry.

Except, you can also get soda ash

from burning seaweed, and that was the start of the brown gold rush.

The beaches of the Western Isles are abundant in this seaweed or kelp.

When burned, it produces soda ash,

so 200 years ago, these quiet shorelines were ablaze with activity.

The remains of the workers' cottages can still be seen.

As the kelp industry boomed,

they housed entire families that depended on the seaweed for their livelihood.

Whatever the weather, they had to be outdoors - cutting, carrying and burning it.

I want to know what life was like in the early 1800s for the people of Skye working the kelp,

so I'm meeting historian Donald William Stewart on this desolate day.

It was a grim task, arduous work, really.

You'd be there knee-deep in freezing cold salt water

for most of the summer months, sewing this stuff up.

Then you'd have to drag it, or haul it, or carry it - backbreaking work - up to the top of the shore where

you'd clean it, you'd dry it, then you'd put it over pits and you burnt it.

And is this men and women working it?

Well, the woman apparently did the burning, if you like.

It was quite a skilled job, you couldn't burn it too fast.

The men, well they took up kelp irons and beat this molten seaweed into blocks,

it cooled down into blueish lumps,

which were then broken up into chunks and taken down to the south.

They're ruins now, but around 200 years ago these coastal houses were hives of activity.

Piles of seaweed burning along the shore,

covering the islands in thick smoke, visible for miles out to sea.

20,000 people across the Western Islands were involved every summer

in this grim, filthy, dirty work,

just as much a product of the industrial revolution as the black coal smoke,

which is belching out of the chimneys in Glasgow and Birmingham, and Manchester.

Crofters and tenants along this coastline were forced into cutting kelp by landlords quick to cash in,

rents were raised and emigration was stopped by an Act of Parliament,

to force more and more workers into the industry.

Tenants here in Sushnis saw little of the profits, their landlord, meanwhile,

Lord MacDonald of Sleat, was making enough cash to turn his house into a castle.

The landlords owned this shoreline, they owned everything that grew on the shore,

that included seaweed and they were really raking it in off the kelp.

At its height, he was making anything up to £20,000 a year off kelp,

that's well over £1 million in today's money,

just an astonishing amount of money to make off seaweed.

Some kelp cutting continued right up to the 20th century,

but those early boom years were short-lived.

When the Napoleonic wars ended,

cheap soda ash from Europe flooded into Britain again.

The glass industry didn't need Scottish seaweed

and so the landowners no longer needed the kelp cutters.

Now almost nothing remains

of the time when the brown gold rush boomed on the Western Isles.

International disputes over territorial waters

can depend on where a country's coastline starts and stops and how long it is.

It's not only governments who are interested in the length of the coastline,

it's also handy to know if you're walking around it.

On a particularly wiggly part of Scotland's shore,

Nick Crane is pacing out a very perplexing puzzle.

It's a question that crops up a lot on Coast -

just how long is the British coastline?

A simple question and you'd think there'd be a simple answer, but you'd be wrong.

If you just zoom out for a moment

and really look at the coastline, especially here in the West of Scotland

and see all those inlets and wiggles, suddenly you're faced with an intriguing problem.

Remarkably, figuring out the precise length of our coastline has led to a whole new branch of maths,

which affects our lives in all kinds of surprising ways, even our mobile phones.

What's going on here, Tony?

I think we should start by making some measurements.

Do you want to give me one of those to carry.

How are we going to do these measurements?

Well, we're going to place these on the either side of two rocks...

Dr Tony Mullholand is a mathematician from Strathclyde University.

He's here to show me that measuring the length of the coastline all depends on the length of your ruler.

Measuring devices...excellent.

Having walked a good bit of our coast, I don't fancy measuring the whole thing.

Instead we're going to concentrate on a tiny bit, but if you think that makes it easy, think again.

OK.

We've placed two tripods 14 metres apart, that's the direct distance between them,

but it doesn't take into account how wiggly the actual shoreline is,

that's what we're going to measure, firstly with a two-metre rule.

That's one, two...

That's 13,

14...

and let's call that 15.

OK. So measuring our bit of coastline with a two-metre rule

we get a length of 30 metres,

so now we're going to do the same measurement with a one-metre rule.

16, 17... I'm not very good at counting over 50.

21, 22...

28, 29...

34...

50, 51...

51, excellent.

Amazingly, with a smaller one-metre rule

the coastline now measures 51 metres,

because we're getting further into those nooks and crannies.

The coast is getting longer!

Now finally with a half-metre rule.

That's if we can get there before the tide comes in.

I never thought I'd see one of Britain's biggest mathematical brains

measuring a coastline with a wooden ruler.

63, 64, 65, 66, 67, 68...

You're on the home straight now.

I'm concentrating! 94.

-I'm I putting you off?

-Yeah. 95...

120... Is this an amphibious ruler?

121...

-Judge the tide...

-123!

So the half-metre rule gives us a reading of nearly 64 metres,

the longest yet and much more than our original straight-line distance.

So the difference between the straight line, which is 14,

and the 50 centimetre ruler of 64, even I can work that out it's 50 metres, isn't it?

It's almost four times the distance.

This is the extraordinary result,

as your ruler gets shorter and shorter,

your measurement gets longer and longer.

Mathematicians realised you could keep going like this forever

and discovering that created a whole new branch of mathematics - fractals.

A fractal is a pattern which reveals greater and greater complexity as you zoom in.

It was actually the endless complexity of Britain's wiggly coastline

that inspired Polish-born mathematician, Benoit Mendelbrot, to invent fractal mathematics.

Mandelbrot realised that, instead of using a ruler,

he could measure wiggliness by giving it a number,

a number between one and two, he called this the fractal dimension.

OK, Nick, let me see if I can try and explain this to you in more simple terms.

Here we have a straight line and this has a fractal dimension of one.

OK.

Here's a more wiggly line and we give this a fractal dimension

somewhere between one and two, this might have a fractal dimension of 1.3.

-So a fractal dimension is a bit like a wiggliness factor.

-Absolutely!

That's just giving you a measure of how wiggly the coastline is,

so I think we'll have a look at a map of the British Isles.

OK.

Now I'm from this part of Britain, I love this coastline

and this is very wiggly and I'd give this a fractal dimension of somewhere about 1.3.

And what about somewhere... I mean I grew up in Norfolk down here, which has got a very smooth coast.

Absolutely and so you can see somewhere like here,

it's got a fractal dimension nearer 1.05, almost down at one,

almost down at one and that's borne out by the coastline.

So, visually, I think you can see this number relates to this ruggedness of the coastline.

Giving a number to how wiggly your shore is might seem academic,

but the length of a country's coast

is vital for international disputes about boundaries.

Everybody's got to agree about how they are measured,

so countries can't cheat using a smaller ruler

to make their border appear longer.

As it happens, the West Coast of Scotland is the second most wiggly coastline in the world.

The prize for the wiggliest goes to Norway.

I've seen the light Tony - fractal dimensions give a numerical value

to this seemingly chaotic coast, but what has it got to do with that?

Ah, well, you've got your car radio, or your radio at home with a long aerial,

excellent reception, we want the same thing for the phone,

but we don't want a long aerial, so what's the solution?

We want to take this long aerial and cram it and squidge it and make it as wiggly as possible,

give it as high a fractal dimension as possible and put it in the phone.

OK, Tony, I get the maths, but the reason I've been clambering up and down rocks all day

is to find out the length of the British coastline. How long is it?

Well, the Ordnance Survey, they'll quote a figure of just over 11,000 miles for mainland Britain.

It has to be borne in mind that that is measured with a ruler that's 10 centimetres long.

-A hypothetical ruler.

-A hypothetical ruler, using satellite imagery and digitised images.

But there's no limit to how short a ruler can be.

The length of the British coastline is infinite.

I didn't want to hear that.

-I'm sorry.

-The coast is infinite.

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