All language subtitles for Ghost Bear Family BBC Natural World 2015 720p HDTV x264 AAC MVGroup org EN SUB_Subtitles01.ENG

In these dark, ancient forests
lives a creature of legend.

This is not an albino
or polar bear,

but a rare North American
black bear known as a ghost bear.

This white bear is a mother
with two black cubs.

A bear family like this can be
found in only one place on Earth.

The rainforest islands
on the west coast of Canada.

My name is Jeff Turner and I'm
a Canadian wildlife film-maker.

Alongside my own family, I'm heading
into this wilderness to tell

the story of these special bears.

There's a lot at stake
for this bear family.

They only have a few critical
months to find enough food to

survive next winter's hibernation.

And they're not alone.

Hungry wolves...

and much larger bears
share their island home.

It's going to take all the skills
of this mother bear to get her

cubs through the many
challenges they'll face.

This is their remarkable story.

Canada's ghost bears live on
the west coast, in an area

known as the Great Bear Rainforest,

part of the world's largest
temperate rainforest.

Here, the North Pacific Ocean

meets the coastal mountains
of British Columbia.

This is one of the most productive
landscapes on the planet,

and the life here is sustained
by an abundance of fresh water.

The Great Bear Rainforest
shelters thousands of different

species beneath its branches...

..but the one that we've come
here to find, the most famous

and elusive, lives
deep within the forest.

This isn't my first time I've been
here looking for ghost bears.

25 years ago, my wife Sue and I

were the first people to ever
make a film about these bears.

We had some amazing experiences
and it changed the way

I have understood and worked
around bears ever since.

Today, we're heading to a spot

where a ghost bear has been
seen in recent years.

Although any bear could be
frightened by human presence,

experience has taught me
that if you're relaxed,

the chances are
the bears will be, too.

And when we find her, this female is
just awakening from a long sleep.

White black bears can
occur in other places,

but it's one in a million
odds, whereas here,

because these bears have been
isolated on these islands for

so long, about one in ten
black bears are white.

This year, she's come out of
the den with two little cubs

that, unlike her, are black.

The genes that create white
fur are not always expressed,

and a ghost bear mother is as
likely to give birth to black cubs

as she is to white ones.

Getting both her cubs through their
first year will be a challenge.

The main risk to cubs comes
from other bears and wolves,

so when they're small, she'll
keep them back here in the forest.

It's safer here because there's
relatively little to eat,

and most animals are
out on the coast,

where one of the year's greatest
feasts is getting underway.

Hundreds of kilometres of shoreline
are covered with sticky, white eggs.

Creatures from around the region
are here to take advantage

of the abundant food.

This hungry male bear could
easily kill the cubs.

But right now, he
seems pretty content

with just licking up
the rich eggs.

Wolves are also a threat to the
cubs, and they're here, too.

At this time of year, they'll spend
hours eating the rich eggs

while trying not to ingest too
much of the seaweed underneath.

All these eggs come
from Pacific herring

that have come up from
deep water to spawn.

Male herring broadcast
their sperm into the water,

turning it milky white.

This attracts females to the area,

who deposit their sticky eggs
onto the vegetation.

Each female can lay up
to 40,000 eggs.

There's a pheromone in the sperm
that stimulates both the males

and females into a frenzy
of spawning activity.

Herring are the most abundant
fish on the coast,

providing rich pickings for any
animal that can take advantage.

Like these Steller sea lions.

The big males can eat up
to 70kg in a day.

DRAMATIC MUSIC

The herring spawn is one of the most
important events of the year...

..but our white bear mother
has not been able to take

advantage of this spring feast.

For now, she's continuing to
keep her cubs hidden away.

They do seem nervous,

but it's not because there
are wolves or other bears around.

We are the first people that
these cubs have ever seen...

..and even though
these cubs seem shy,

we know what's possible
in a relationship

between humans and bears.

25 years ago, we lived side-by-side
with the bears of the

Great Bear Rainforest, when our
daughter Chelsea was just a baby.

SHE BABBLES

We quickly came to realise
that these bears had never

encountered people before.

Over time, we were able
to gain their trust,

so that they were
comfortable allowing us

close enough to get a
special view of their world.

Growing up with bears as her
neighbours became normal to Chelsea.

CHELSEA: I don't remember
being here as a child,

but the experience must
have rubbed off on me,

because today, I feel instinctively
comfortable around bears.

It's really special to be able
to share this again with my dad,

only this time, I know how
lucky I am to have such close,

personal encounters with bears.

Looking at her, this
mother bear seems thin.

She needs to build herself up

if she's going to get her cubs
through their first summer.

Black bear mothers produce
milk that is 30% fat,

some of the richest milk of
any land animal in the world.

And she's had to do this
with only plants to eat.

Since coming out of the den,
she's been slowly losing weight.

She needs high-protein food,

but she'll have to wait
until the salmon arrive.

Waiting in the forest does offer her

and her cubs continued sanctuary,
but it must be hard to stay back

from the coast, where the
pickings are much richer.

Other inhabitants of these
islands can take full advantage

of what this place has to offer.

The Great Bear Rainforest
lies adjacent to the

North Pacific Ocean,
one of the richest in the world.

The wolves have readily adapted to
life in this marine environment.

They are more sea wolves
than timber wolves.

They are genetically distinct
from their cousins on the mainland

and are incredible swimmers.

They've been seen travelling up
to 12km between islands.

SOMBRE MUSIC

Most of the food these wolves
eat comes from the sea,

but they also eat bears.

A wolf pack kills at least
one or two bears a year

in the Great Bear Rainforest.

There's a good reason the mother
bear prefers the forest,

even though there's less to eat.

But with summer's imminent arrival,

she shouldn't have to wait much
longer for a decent meal.

Millions of salmon are migrating
from their distant offshore

feeding grounds, returning to the
rivers where they were born,

to spawn and then die.

Many will swim hundreds
of kilometres inland,

deep into the heart of the forest.

And for some, it will mean
they have to travel underground.

Underlying huge parts of the coast
is a type of bedrock that is

so porous and permeable that
water flowing on the surface

will suddenly disappear into a hole.

The water flows underground,
often for kilometres,

before re-emerging again, sometimes
in a completely different valley.

In these regions,
known as karst landscapes,

salmon may have to travel
through many of these underground

river systems to reach
their spawning grounds.

The water that flows through this
special bedrock becomes very

alkaline and carries nutrients
leached from the rocks.

Ideal for salmon.

This salmon creek is fairly small,
but it's full of fish.

This could be a great spot to set up
and wait for the mother bear...

..even though there are other
bears here already.

This huge male is one of the
biggest black bears I've ever seen.

He must be the dominant
bear on the creek,

and could be a real problem
for a mother bear with cubs.

There is at least a dozen bears
that use this creek,

so I'm not sure our mother
will make an appearance.

The salmon only have a few weeks
to spawn before they die,

but many won't get the chance.

Those white paws definitely
belong to a ghost bear...

..and I'm relieved to see
that it's the mother bear.

She has been lured from the forest
by the chance of a good meal.

This will be the first salmon
she's tasted in almost a year.

Hopefully, the first of many.

But she's left her
cubs behind in the forest.

Although they'll be alone, with all
the other bears on the creek,

it's probably the right call.

There are so many salmon here,

it's almost like she doesn't
know where to start.

PLAYFUL MUSIC

And it looks like she's not going
to settle for just one.

I've never seen a bear with one
salmon in its mouth

trying to catch another.

She's either really experienced,
or very hungry.

Right now, it's still too risky
to bring the cubs to the salmon...

..instead it looks like she's
taking the salmon to the cubs.

It didn't take me long to learn
that the mother bear

liked to eat her salmon beneath
a particular tree

that the cubs were often in.

So I was able to set up a remote
camera right there

to observe what the cubs thought
of their first salmon.

One cub was quick to the dinner
table,

but the other was definitely
a little more cautious.

And he seemed far more curious
about my camera,

than about the fresh salmon his
mother brought him to eat.

While the mother bear seems

completely unconcerned by my camera,

she has other worries.

Keeping the cubs in the forest

will really limit her fishing-time.

Soon she is going to have to risk
bringing them to the creek.

And she doesn't wait long.

With no other bears around,

she makes the move.

This is a big moment in
the cubs' lives.

She's got to be careful, though,

another bear could turn up
at any moment.

The cubs are a bit nervous being
out in the creek,

and they know they have to stick
close to her wherever she goes.

While there are still lots of salmon
around,

the mother bear can be selective
with what she eats.

She takes a bite of this salmon...

and then drops it.

She can probably tell from the taste
it's a male.

Bears need to target the richest,
most nutritious food source.

What she really wants to find
are female salmon...

..and she'll go out of her way
to catch one.

Female salmon are loaded

with thousands of brightly coloured,
nutrient-rich eggs.

This is the best part of the salmon,

high in calories and fat...

and she doesn't want
to leave any behind.

The cubs, though,
still need to learn

which are the best parts to eat.

Though the cubs are still nursing,

they need these protein-rich salmon
as much as their mum does.

The whole family has to put on
as much weight as possible

before winter hibernation.

The mother bear is always alert
to potential dangers to her cubs.

Surprisingly,
it's another ghost bear.

This one looks like a large male.

The cubs know that when another
bear is around,

they have to get out of there.

They retreat to the safety
of the trees.

The mother bear is much
smaller than him,

but she's still going
right after him.

I'm not sure that's such
a good idea -

he could certainly do some
damage to her.

And he doesn't seem much
deterred by her approach.

That's a risky move on her part.

Any time two bears
physically interact like that,

there's a good chance one of them
could be hurt.

They're very powerful animals.

I don't know her character
well enough yet to decide

if she's foolhardy or brave.

Only time will tell.

But her cubs knew what to do in
this situation -

they knew that their best defence
was to get up as high into a tree,

as quickly as possible.

Bear cubs always seem so at ease
in these big trees,

so far off the ground.

They'll use their teeth as well
as their claws

to hang on and move around.

The mother bear seems to have won
the day,

but these encounters with other
bears will be stressful for her.

She wisely decides to take her cubs
back into the safety of forest.

With the arrival of the salmon,

the mother bear may also have to
worry about the resident wolf packs.

Wolves on this coast are known
to catch salmon in these streams.

It's lucky for her the ocean
provides such a bounty

that the wolves seem content
to spend their time

patrolling the shoreline.

And they find a dead sea lion
that has washed up onto shore.

The whiter wolf is the old
grandmother of the pack.

Her teeth aren't strong enough

to chew through the tough,
rubbery hide,

as this younger wolf is
starting to do.

For now, the old wolf must scavenge
the beach for smaller prey.

THEY HOWL

Wolves use howls to communicate.

When they find food they alert the
other pack members to the discovery.

The abundance of food from the ocean
means that these sea wolves

can survive on just
60 square kilometres,

whereas wolves inland can range
well over 1,000.

This is a real bonanza for them -

many kilos of fat-rich meat -

and it will feed the pack
for a week or more.

Eventually, even the old grandmother
wolf gets her chance to feed.

The younger pack members have peeled
back the hide

and the heat from the sun
has softened the carcass

so she is able to eat her fill.

While the summer sun has helped
this old wolf get a meal,

it brings tougher times for some
of the other residents

of the Great Bear Rainforest.

Water levels on the creek
are dropping,

and it's getting harder for
the bears to catch salmon.

The salmon can't make it up and over
the falls now...

..so they hole up in the remaining
deepwater pools.

The bears keep trying...

but salmon are very deep difficult
to catch in deep water.

Chelsea and I are going to set up
our underwater camera

in one of the pools to get
a salmon's-eye view.

We wanted to test a theory about why
ghost bears are so prevalent here.

We want to find out if white bears
catch more fish than black ones.

There's new research that indicates
they can catch 30% more salmon

during the day than black bears,

because their white fur

is less visible against the sky.

This would give them a distinct
survival advantage.

Salmon have excellent vision -
surprisingly similar to humans.

We need to place the camera

so that it's just the right spot
to see the bears against the sky.

My dad asks me to do my best
bear imitation!

Once we are happy with the camera
replacement,

we just have to wait.

It's not long before a black
bear arrives.

From the salmon's perspective,

he seems to blend in very well
against the trees.

He even makes a lucky catch.

On this narrow creek, the forest
obscures most of the sky above...

..then I see our mother bear
approaching.

She seems to stand out even more
against the trees

than the black bear.

But she still makes
a successful catch.

Later we pointed the camera
more towards the sky

and she did seem better camouflaged.

It wasn't a very scientific test,

but I think a bear's fishing
ability

is as much to do with its age
and experience,

as it does with its fur-colour.

The more time we get to spend around
this bear,

the more we are learning about
her skills.

So far, she's managed to catch lots
of fish and keep her cubs safe.

But the busiest and most important
part of the salmon season

is still to come.

While the mother bear lives on
these islands year-round,

there are other creatures
that only come for a visit.

These are North Pacific
humpback whales...

..and 25 years ago you rarely
saw them on this coast.

Today, there are about 2,000 that
spend the summer on BC's coast.

The humpbacks feed by lunging
sideways into the water...

..gulping down millions of
tiny krill in massive mouthfuls.

The humpbacks share their summer
feeding grounds

with Steller sea lions.

GURGLING, BARKING GROWLS

The juvenile sea lions

are very curious about
their giant neighbours.

Filming at sea level, it wasn't
clear exactly what was going on.

Were the sea lions trying to feed
around whales,

or were they trying to play
with them?

We just couldn't tell.

By using our small remote-control
aerial camera,

my son Logan was able to capture

a bird's-eye view.

With the footage from above,
we could see that the sea lions

were taking turns swimming closer
and closer to the humpbacks -

like dare-devilish teenagers.

And we could see now that the
humpbacks were clearly not happy

with the sea lions' antics.

This tail side-swiping is a sign
of aggression in whales.

For the sea lions,
it's a dangerous game -

a smack from a humpback's tail
would be deadly.

The humpbacks slap the water
with their pectoral fins and tails

in an effort to drive off the pesky
sea lions.

While the humpbacks have made
a remarkable recovery,

on this part of the coast,
their future is far from secure.

There are plans to ship oil and gas
in massive tankers

right through the heart of
the Great Bear Rainforest.

Humpbacks have no biosonar
capacities

and are therefore very vulnerable
to collisions with large ships.

The traffic in these waters

is expected to climb more than
100-fold

if the planned pipelines and tanker
depots get built.

It's not just whales that may
be impacted...

..these rich, coastal waters
provide foraging opportunities

for lots of other wildlife.

Sea birds like these gulls,
loons and guillemots

are all here to take advantage of
the schools of young herring

living in these inland waters.

The guillemots are expert
underwater hunters.

They can easily dive up
to 100 metres.

Herring will avoid swimming
through bubbles.

The guillemots take advantage
of this to corral the herring

and drive them up to the water's
surface.

The trails of bubbles are air
trapped in the guillemots' feathers

and squeezed out by the
water pressure as they dive.

The guillemots remain underwater
for several minutes as they herd

the frenzied herring into bigger
and bigger bait balls.

Forming a bait ball is the herrings'
last-ditch defence.

With the guillemots pushing them
up from below,

the herring are driven
to the surface

where the gulls have been waiting
to attack.

Many dive into the bait ball
to try and make a catch.

But some try a different
technique...

Piracy!

These feeding frenzies don't
last long, though,

the herring eventually escape diving
deep out of reach

of these surface predators.

Back on the salmon creek,

the water is low and the mother bear
is spending more time

out here with her cubs scavenging
salmon carcasses.

Fishing is tough right now.

What's nice to see is how
increasingly tolerant

she's becoming of us.

She just goes about her day
like we're not even here.

This is because the people she has
met before

have treated her well.

We're collaborating with local
bear guide

Marvin Robinson, a member
of the Gitga'at First Nation.

He spent a lot of time

among the white bears in his
traditional territory,

protecting them and guiding
photographers and tourists

to see them.

He has treated the bears
with respect and tolerance.

This has really helped us
establish a relationship

with this mother bear.

She is so comfortable
in our presence -

she'll even take a nap
right in front of us.

In fact, she's looking so relaxed
it's actually a little worrying.

While she doesn't need to be
concerned with us,

she still does need to watch out
for other bears.

At least the cubs are up in a tree.

If she wants to avoid a close
encounter with another bear,

she needs to literally sleep
with one eye open.

And this is what I was worried
about.

This big male doesn't know
the mother bear

is asleep on the other side
of the tree.

His sudden appearance startles her.

LOUD GROWLING

She has no idea of his intentions.

LOW GROWLING

She is very upset
by how close he got

and reacts with real aggression.

GROWLING CONTINUES

This is just the sort of encounter

that most mother bears try to avoid.

It was a dangerous situation for her
to get yourself into.

She is lucky the big male
didn't fight back.

He's so much bigger than her

that one swipe of his paw could've
injured or even killed her.

For bears at this time of year,

the stakes are high.

And the next morning brings a stark
reminder of just how high.

It's a little male black bear.

He was most likely killed in a fight
with another bear -

possibly the big male.

Competition for salmon can be
fierce and, occasionally, fatal.

The presence of this dead bear

appears to have really upset
the mother.

She needs the salmon,

but the risk to her cubs is too high
to stay out on the creek right now.

Luckily, this stressful situation
is about to change.

The autumn rains finally arrive
after a long, dry summer.

This place is called the Great
Bear Rainforest for a reason -

more than three metres of rain falls
on these forests every year.

It is one of the wettest places
in the northern hemisphere.

This huge influx of fresh water

cascades off the rocky
mountain slopes

filling the streams and creating
surging waterfalls.

Rising water levels

mean that the salmon that have been
trapped in shallow water,

can now continue their migration
upstream.

But the higher water means that
it can sometimes take 24 hours

and dozens of attempts

for them to leap a single waterfall.

The salmons' efforts are made even
more challenging

by the presence
of hungry black bears.

These two bears are very skinny.

They've both been drawn
to the falls

in a desperate attempt to catch one
of the leaping salmon.

But they have to be in exactly
the right position,

just a little bit off the mark

and they won't catch a thing.

This bear knows he needs a better
position to fish,

but there is a real danger -

a fall into this surging water
could be fatal.

Not only does he have to stand
in this fast water,

but he has to be secure enough
to reach for leaping fish.

The other bear needs to get closer,

but there's no place for him
to stand.

They are so close...

And yet, just out of reach.

The bear on the other side of
the fall looks on in vain...

He is just too high above the water.

But this bear's precarious
position finally pays off.

With water levels up on the creek,

the salmon are
able to push further upstream

and the bears have more
opportunities to catch them.

With higher water, the mother bear
has moved to the falls

where the salmon are most active.

But the big male has taken over
the best fishing spot.

She needs to keep herself safe,

but she also needs access
to salmon.

She cautiously moves closer
to the big male.

She's probably still a little
unsure of him

after their last encounter.

There's lots of salmon swimming
through the falls now,

but with big male so close by,

she can't really move around
as freely as she needs to.

The big male has control
of the best fishing site.

But due to the closeness
of the mother bear,

he also seems to be losing some
of his focus.

MALE BEAR GROWLS

Then he manages to grab
another salmon.

However, this one is a male,
and he lets it go.

The mother bear is less fussy
right now,

but she's unable to take advantage
of the opportunity.

Neither bear is very happy
with the presence of the other.

The mother bear decides to move in

and take advantage of the scraps
the big guy's left behind.

The big male seems annoyed by her
presence so close behind him.

Something has to give.

At this rate, neither bear
is going to be successful.

The mother is getting more
confident...

growling at the big male,

letting him know she wants him
out of there.

Finally, she builds up the nerve
to storm his position.

GROWLING

LOW, SUSTAINED GROWLING

Even though she's much smaller
than him, she's not backing down.

She wants access to the salmon
more than he does.

The big male tries to intimidate
her with his much larger size...

..but she holds her nerve -
refusing to leave.

Finally, the big male's
had enough,

and moves on to other
fishing grounds.

Now the mother bear has the falls
all to herself.

This has been a hard-won salmon,

but I think there's going to be
lots more where this came from now.

Watching her these past months

I've really been impressed
by how well she's done

for herself and her family.

She's a committed mother, who will
do what it takes

to provide for her cubs
and keep them safe.

As winter approaches, they should be
in good shape for hibernation.

But she still had one more surprise
in store for me.

On the very last day of filming,

she allows me to get the camera
close enough to her cubs

to see the world through the eyes
of an individual bear.

25 years ago, when Sue and I
first came here,

we had never before been in a place
where the wildlife allowed us

to get so immersed in their world.

It's been such a privilege to be
able to come back here

all these years later

and have the opportunity to see even
closer into the world of bears.

It's a testament to just how special
the Great Bear Rainforest is -

this temperate rainforest right
next to

the cold, rich North Pacific Ocean

combine to make this a unique
environment full of life.

And nowhere else on the planet

can you find a family of bears
like this.

With such a great role model
to follow,

I don't think these cubs will have
any trouble

eventually making their own way
on these islands they call home.

As a wildlife film-maker

I've had the opportunity to film
all around the world,

but coming back here to the
Great Bear Rainforest with my family

reminds me again what a unique
and extraordinary place this is.

There's nowhere like it in the world

and it needs to be celebrated
and protected.

There is such richness and diversity
everywhere you look,

but during our filming we discovered

that it still had some amazing
secrets to reveal.

The Great Bear Rainforest
on the west coast of Canada,

is a huge, largely intact,
wilderness

74,000 square kilometres in size.

British Columbia contains
one fourth

of all the temperate rainforests
left on Earth.

It's a forested archipelago
of thousands of islands,

fjords and inlets.

What makes this place so unique

is the fact that it's adjacent
to the rich North Pacific Ocean.

The sea here supports
an abundance of life.

Harbour seals spend all year
here feeding.

Surf scoters...

..and the aptly named
goldeneye ducks,

travel here to feed
on the abundant fish.

During our past visits

we've always focused our filming
efforts on the land,

but there's an incredibly rich
world beneath the surface.

Kelp thrive in these cold
fast-moving waters.

It's one of the fastest-growing
plants on Earth

and can reach up to 30 metres
in height.

This is the first time we've taken
our cameras underwater

to film the kelp forests.

And for the seals that lived here,

they were just as curious of our
cameras as we were of them.

Each kelp strand provides
a habitat for up to 200 species

and tens of thousands of individual
creatures.

When we first filmed here
25 years ago,

there were no sea otters in
this part of the central coast.

They were hunted to extinction

all along British Columbia's coast.

A small number were reintroduced
about 40 years ago

and the richness of this environment

has allowed the population to grow
to more than 5,000 today.

They are re-colonising areas of
the coast

that have not had sea otters
for 100 years.

Another success story on this
coast

has been the arrival of the Pacific
white-sided dolphin.

These agile hunters can reach
speeds of up to 40km an hour.

25 years ago, they were virtually
non-existent here.

Now, about 20,000 are making these
inshore waters their home.

The productivity of life
beneath the sea,

is directly linked to
that of the forest above.

Along the boundary between the sea
and the forest,

sandhill cranes arrive
to spend the summer.

CROAKING CALLS

Pairs return from California
every year to breed

and raise their young in this rich
forest environment.

Their distinctive resonant cry
can carry up to 5km.

These temperate forests harbour
a greater abundance of life

than any other type of forest
on earth.

A big part of the reason for this

is due to what's
happening beneath the surface.

It has to do with the way water
flows through,

and even beneath, this forest.

Many of the trees grow on
the permeable karst bedrock.

Here the land is so soft
and fractured,

that water flowing on the surface

can suddenly disappear through
a hole in the ground.

Down here there are many kilometres
of underground tunnels and chambers

that the water flows through.

It's this water that's the key
to the forest's success.

Wherever this soluble karst bedrock
occurs,

the trees grow to incredible
heights.

The soil that develops on top
of this bedrock is well-drained,

so the tree roots
don't get waterlogged.

If the soil was removed
you could see

the convoluted and cracked surface
of the bedrock

that the rainwater flows through.

This type of carbonate bedrock
is rich in nutrients.

The eroding rainwater
carries these nutrients

throughout the karst system
feeding the trees.

And this makes them highly prized
by timber companies.

Many of them, especially on
Vancouver Island,

have already been logged.

When the trees are cut down,

the thin topsoil is vulnerable.

If a fire occurs,

this soil can be washed away
exposing the bare karst rock below.

It could take hundreds of years
before a site recovers.

I was keen to document life
beneath these forests.

It's an important part
of the salmons' story.

Filming in these underground rivers

was something that had never been
attempted before,

and I knew I needed help
to make it happen.

Whoa!

So, let's put it down there,
try to run it through the tunnel.

If it doesn't fit, we'll leave it
back on the left, then assemble it

and we can just form a little
line in.

Travelling light today.

'The first challenge was getting
hundreds of kilograms

'of diving and underwater camera
gear into the caves.'

Put it just below you, and then
we'll stage everything down to here.

All this for one shot!

THEY LAUGH

'This was no place for anyone who
might suffer with claustrophobia!'

Go ahead of me there.

That's a bit of a squish, isn't it?

It's quite exciting. OK. Yeah.

'This was a first for all of us.

'We were exploring a hidden world.'

It's an amazing experience being
under here.

These formations you just had
no idea existed here.

'Once we got through the narrow
part of the cave,

'it opened up into larger chambers.'

During the wet season,
these tunnels can fill with water.

But eventually, we arrived at this
underground lake,

where we heard the salmon had been
seen in the past.

This is one of the deepest
freshwater cave dives in Canada.

The water is connected to the river
that flows above ground,

so fish like this sculpin can move
in and out of the caves.

For the dive team,
this is a cause for concern.

I heard that the current can get up
to eight knots

in certain places here. That's way
too strong to swim against.

It looks OK, Alex?

I think it looks good.

'Once the guys decided the current
was safe, they were in the water,

and their camera gear was lighting
up this dark underwater world.

It didn't take long until
the salmon showed up,

drawn to the sudden appearance
of light.

This is the first time that
salmon have been filmed

in these underground karst caves.

While the salmon may have to
navigate these cave systems,

the water here offers them
something extra.

Thanks to the alkaline karst
bedrock,

the water here is particularly rich
in nutrients and aquatic insects

offering rich pickings
to hungry salmon.

Research in Alaska shows that
salmon living in karst streams

tend to be larger and more numerous
than in other rivers.

It's become clear to me that
the karst landscapes

of the Great Bear Rainforest

are vitally important to the animals
that make their home here.

But it's also a fragile landscape.

Without stronger protection
for these karst regions,

we may lose a key component

of what makes the Great Bear
Rainforest

such a rich and diverse wilderness.

And home to some very special
wildlife.