Original subtitles

Vancouver Island is the largest island

on the west coast of North America.

All the habitats of this island...

..its mountains...

its freshwater...

..and its forests...

..are deeply connected to the sea.

And every animal,

from the largest to the smallest...

..has to find a way to fit into that unique alliance

to survive.

(ROARING)

From the Arctic...

..to the tropics...

..islands are wild laboratories...

..where unique rules apply...

..and nature puts life...

..to the ultimate test.

(GROWLS)

Surrounded by the North Pacific,

Vancouver Island has a deep connection to the ocean.

From its snow-capped mountain range

and vast network of freshwater lakes and rivers...

..to its ancient rainforest...

..and ocean inlets that cut deep into the island.

But it's the most intense along its western edge.

The outer coast of Vancouver Island

is exposed to the full force of the vast Pacific.

It's a volatile environment...

..unpredictable, but full of opportunities.

It's prime hunting ground for the island's dominant predator.

A wolf family is on the prowl for any food

that the ocean may have thrown onto the island's shore.

(EAGLE SQUAWKS)

(SNIFFING)

These are sea wolves,

smaller and genetically distinct from their mainland cousins.

(SNIFFING)

90% of their diet comes from the sea.

(SNIFFING)

Today, they are only finding small fish and invertebrates

hiding under the rocks.

But the island is about to lay on a massive feast.

(DISTANT WOLF HOWLS)

(GULLS SQUAWKING)

From deep water out in the Pacific...

..herring, in their millions, are arriving.

The herring are coming up to the island's rocky reefs to spawn.

Females stick their eggs onto the rocks and seaweed.

Males broadcast their sperm,

changing the colour of the sea.

The spawn can be so vast

as to be visible from space.

With so many spawning fish crowding the island's shallow waters,

these are perfect conditions for a feeding frenzy.

(DRAMATIC MUSIC)

A single sea lion can eat half a tonne of herring

during the spawn.

The eggs are also a big part of this spring feast

for lots of animals...

like sea otters.

There can be hundreds of thousands of them

on every square metre of coastline.

And even migrating birds time their journey north

for this annual event.

A big male black bear has just woken from hibernation.

(BEAR HUFFING)

He hasn't eaten in four months.

This protein-rich food helps to restart his body's metabolism.

Even a top predator like the wolf

will spend hours eating these tiny morsels.

But the spawn only lasts a week.

Soon, he'll be back to patrolling the outer coast,

looking for his next meal.

On this island, the impact of the sea runs deep.

Thousands of years ago,

the glaciers that covered the island carved deep channels

into its bedrock.

When the ice retreated,

the island let the ocean into many of these channels,

creating hundreds of kilometres of protected tree-lined coast.

This realm is always in motion.

Tides rise and fall over four metres

every six hours...

..revealing secret food supplies...

..and then hiding them again.

It's all about timing.

Trees along the inlet's shore provide security

for a mother black bear and her two new cubs.

(HIGH-PITCHED YAPS)

Only a few months old,

everything out here is new to them.

Rocks left behind as the glaciers melted

are good hunting grounds for intertidal creatures, like crabs.

(SNIFFING)

The cubs learn by watching their mum.

(BIRD SQUAWKS)

They have a lot to learn about seafood.

They need to eat a lot of crabs,

mussels, barnacles, and fish, in the next five months,

to gain enough weight to survive winter hibernation.

(BEAR SNIFFING)

(GRUNTS)

A big male bear is also trying his luck

in the intertidal zone.

Mum's unaware of him across the inlet...

(OMINOUS MUSIC)

..but not for long. (GRUNTS)

Male bears sometimes try to kill young cubs...

..either to bring the mother into breeding readiness again...

..or simply to eat them.

Mum's got to get her cubs out of here...

..before he gets too close.

(CUB WHINES)

(CUB CRIES)

(OMINOUS MUSIC BUILDING)

The tall trees along the shoreline

prove vital to this family now.

The cubs are born excellent climbers,

a skill that can save their lives.

The thin branches near the top

can't support a big bear.

Big trees along the island's inlet

also provide an excellent vantage...

..for some of the sharpest eyes in the animal kingdom.

(EAGLE CHIRPS)

Bald eagles can only catch fish within half a metre of the surface.

So, these calm inlet waters

help them spot their prey.

A tall tree, just above their ocean pantry...

is also a perfect place

to raise chicks. (CHICKS CHEEPING)

(MELLOW MUSIC)

Mum comes back with breakfast.

Now, Dad gets a chance to stretch his wings.

Competition between chicks is strong.

(CHEEPING)

Usually, only one survives.

And catching enough for two growing chicks will get harder...

when hot summer weather drives fish deeper into cool water.

This island will put the eagle family to the test

in the months to come.

Oceans of salt water surround Vancouver Island,

but its heart is a vast network

of freshwater lakes and rivers.

The freshwater network is sustained almost entirely

by melting snow and ice

flowing off the island's mountains.

Water temperature can vary widely through the seasons,

so to thrive here,

you have to know how to go with the flow.

In the spring, heat and light concentrate food production,

like algae growth near the surface...

..where a western toad tadpole is heading up to feed.

He doesn't have any parents to protect him...

..but he's got company.

Each morning, he's joined by the three million

other tadpoles he was born with.

For these tiny tadpoles,

it's an epic daily migration.

The tadpoles feast on algae

growing near the warmer surface waters...

..making them easier to find.

Freshwater leeches hunt without eyes or ears.

They zero in on their prey

by sensing vibrations in the water.

(OMINOUS MUSIC)

They can hold prey with tremendous force

despite their small size.

Escape seems impossible.

But his luck is in today.

Over the next few weeks,

the tadpoles will feed voraciously

before morphing into adults

and escaping the island's water realm.

Then the freshwater network will be taken over by another species

that will transform the entire island.

Vancouver Island hasn't always sat snuggly alongside

the North American continent.

Two hundred million years ago,

its rocks were part of the ocean crust,

thousands of kilometres offshore.

Over millions of years, it crept closer and closer

until it merged with the continental landmass.

A large part of the island today is still made up of that ancient rock

borne from the seafloor.

Limestone.

It's made from the skeletal remains

of trillions of ancient sea creatures...

..and is loaded with minerals.

And it lies under most of the island's temperate rainforest.

The temperate rainforest is the island's largest,

and most productive habitat.

And, of course, any rainforest... needs rain.

It arrives in moisture-laden clouds formed over the ocean,

that rise over the island's forest mountain slopes.

Up to four metres of rain falls every year.

(FROG CROAKING)

It is one of the wettest non-tropical places on the planet.

All this rain shapes the island's surface in surprising ways.

Over the millennia,

the soft limestone of the island has been eroded,

creating the highest concentration of caves

found anywhere in North America.

And the limestone's minerals, washed out by the rain,

help grow some of the world's biggest trees.

One reason that these temperate rainforests

hold more carbon per hectare than any other habitat on Earth.

(BIRDS TWITTERING)

(RAIN PATTERING GENTLY)

Rain is critical to life here...

..especially for the wandering salamander.

These amphibians don't have lungs

but absorb oxygen directly through moisture on their skin,

so the wetter... the better.

This island is like a wild laboratory,

creating special conditions for life

found nowhere else.

In the upper canopy,

there are new species still being discovered.

Millions of tiny insects,

many no bigger than a pinhead...

..that spend their whole lives in clumps of wet moss,

60 metres above the forest floor.

In our world today,

this ancient rainforest is irreplaceable.

(BIRDS TWITTERING)

(MACHINERY WHIRRING)

But it's disappearing at an alarming rate.

(TREE TRUNKS CRACKING) Over ten thousand hectares

of old growth forest on Vancouver Island

are cut each year.

Over the last 150 years,

humans have cut down 77%

of Vancouver Island's forests.

Of the most productive old growth forest,

only 3% remains.

It takes several centuries for these ancient forests to develop.

(BIRDS TWITTERING)

Once cut, they'll never get the chance to grow old again.

A 350-kilometre-long backbone of mountains

runs through the centre of the island.

These peaks are almost 2,000 metres above sea level,

but still influenced by the ocean.

Moisture carried in by the clouds

falls as snow for most of the year.

It lingers into summer,

making the growing season short...

..a real challenge for plant-eaters,

like the Vancouver Island marmot...

..one of the rarest mammals on Earth.

There's only 250 left.

Found only on this island,

they've been badly affected by logging

and other changes humans have made here.

The island's mountains give them only a few months to find enough food

to prepare for next winter's hibernation.

So, mosquitoes are an unwelcome distraction.

Marmots are social animals,

living in colonies of multiple families.

Wrestling is one way that they strengthen their social bonds.

Though, it can distract you from potential dangers.

A single predator can wipe out the entire colony.

Their lookout needs to be alert.

(MARMOT SQUEALING)

(SQUEALING CONTINUES)

The numbers are stable for now,

but with so few left,

and isolated on these mountaintops,

the Vancouver Island marmot population

can't afford to lose anyone.

Along Vancouver Island's stormy outer shores,

great quantities of logs and driftwood accumulate.

Beneath this jumble of dense wood,

there's a dry and dark world...

..where a fearsome predator lies in wait.

A female black widow spider.

Her venom poses little threat to humans...

..but to an ant... it's deadly.

Her web lacks the usual spider design aesthetic...

..but there is method in this apparent madness.

Sticky web lines run to the ground...

..perfect for catching ants.

(DRAMATIC MUSIC BUILDING)

She uses her silk to secure her catch...

..and injects venom and enzymes

to kill and liquefy the body.

Later, she'll return

to drink up the fruits of her labour.

This driftwood provides her with the perfect home

in the stormy and harsh outer coast habitat.

When you rely on finding food on the island's shore,

it's either feast or famine.

And it's famine for the wolves right now.

In summer, storms are rare,

so, not much washes onto the shore.

But today, he smells something promising on the air.

(SNIFFING)

To follow his nose,

the father wolf is going to have to swim.

Life on this island gives him lots of practice.

Though it's draining to swim in water barely above freezing.

He's desperate to find food for his family.

(WHINING, YAPPING)

He has seven new pups.

Everyone is hungry.

And his mate has nothing for them either.

Already a couple of months old,

these pups are discovering that the island's shore

can provide for them.

But at this age, they don't have much skill.

They are growing fast and need food now more than ever.

(HOWLING)

(DISTANT HOWLING)

The fate of the wolf family

depends on their dad's ability to find food

in this unpredictable habitat.

(DISTANT HOWLING CONTINUES)

Hot summer weather has warmed the tidal inlet's surface waters.

Fish are deep, where the water is cool...

..so fishing has been hard.

(CHICK SQUEALS)

There's only one chick left now.

The parents couldn't catch enough to keep them both alive.

The surviving chick is fully grown,

but she can't fly.

She needs all the energy she can get right now

to prepare for her first flight.

Flapping builds her flight muscles.

Finally, she's ready to go.

(MAJESTIC MUSIC)

She makes a perfect first flight.

Her parents will bring her food for a few more weeks,

but soon... she needs to hunt for herself.

While fishing conditions are tough right now,

a new wave of opportunities will arrive with autumn.

Vancouver Island's outer coast is dotted with many tiny islets,

surrounded by a shallow sea...

..a habitat created thousands of years ago

at the end of the last Ice Age.

The island was weighed down under a kilometre-thick ice sheet.

But when the ice melted,

the island's mass rose up.

It created many new, little islets off the coast

with shallower water between them...

..a sweet spot for life to flourish

on the edge of a cold, deep ocean.

Sunlight can penetrate to the ocean floor,

fuelling the growth of giant Pacific kelp.

It can grow over half a metre in a day,

creating great underwater forests full of life.

It's a rich and productive habitat

for the world's smallest marine mammals...

..sea otters.

This mother and her baby

rely on all the food that they can find in the rich,

shallow sea kelp forests around the island's edge.

(PUP CHIRPS)

But they are also key players

in the survival of this underwater habitat.

Sea urchins are voracious grazers...

..and they love kelp.

They have tiny tube feet between their stiff spines...

..that they use to move across the sea floor.

But left unchecked,

they can wipe out most of the plant life...

..impacting the whole marine environment.

But where there are sea otters,

they can keep them in check.

The mother sea otter can eat dozens of them every day.

Urchins can't move fast enough to escape a hunting otter...

..so they employ a different strategy.

Using their tube feet,

they try to hide.

But sea otters still get enough of them

to protect the island's kelp forest...

..and maintain the biodiversity on its outer coast.

It's autumn on Vancouver Island,

and its rivers have begun to call in an animal

that will turn the tide in every corner of the island.

Salmon are returning from years spent far out in the Pacific.

They've been following the smell of the tiniest drops of fresh water

amongst billions of litres of ocean water.

It's led them to the mouth of the river where they were born.

And a welcoming committee is waiting.

This is the biggest moment of the year

for the island's black bears.

(GROWLS)

(DRAMATIC MUSIC)

Making it through winter hibernation

depends on how much salmon they can catch.

(GROWLS)

The bear cubs have grown a lot,

but still need to put on more weight.

And they haven't learned to fish yet.

It means the mother bear has to catch salmon for three...

..and it's life-and-death out here.

(ROARS)

Tensions are high.

(ROARING)

For one cub... (CUB CRIES)

..it's just too much.

(GRUNTING)

He's going to watch from the safety of the treetop.

But the other, doesn't seem fazed by the action out here.

She wants to try and catch something of her own.

Mum shows her how it's done.

(ROARS)

The bold cub wants some of that.

Hunger seems to overcome fear.

(GROWLING)

(SQUEALS)

But salmon fishing is just too scary.

She missed.

But maybe there's another way.

That big male's got one.

Doesn't matter he's twice her size...

..she'll do anything to feed her cubs.

(BOTH ROARING)

Naked aggression pays off.

With a mother like this,

both cubs are going to be in good shape

to make it through the winter.

(CUB YAPS)

For the young eagle,

the return of the salmon is a real lifeline.

(SQUAWKS)

Her parents have stopped feeding her,

and she hasn't eaten for days.

But with all the salmon in these shallow rivers...

..this is her best chance to catch her first fish.

It takes a lot of eye-talon coordination.

(DRAMATIC MUSIC)

And her timing...

is off.

But she has to keep trying.

(SQUAWKS)

(DRAMATIC MUSIC BUILDING)

She's done it.

The island's freshwater habitat will provide her

with plenty of practice over the coming weeks,

to set herself up for winter.

As autumn progresses,

the island draws the ocean's bounty deeper inland.

Like arteries,

the island's river network distributes these returning fish

deep into its heartland.

The salmon are trying to reach

the spawning grounds where they hatched.

Many of these rivers flow through the island's limestone cave network.

It's one of the only places on the planet

that has a salmon migration underneath the forest.

In the heart of the island,

the salmon reach their final destination.

They begin to dig the nests and lay the eggs

that will start their epic life cycle all over again...

..and bind their offspring's fate to the island.

The freshwater network has now distributed thousands of tonnes

of ocean-raised salmon throughout the island.

It's here, that the bears play a critical role

in replenishing the island.

(DRAMATIC MUSIC)

They move the salmon from the freshwater habitat

into the depths of the rainforest.

The discarded remains are full of ocean nutrients

like nitrogen and phosphorus.

When the salmon decay, they fertilise the forest.

It's how the trees in this rainforest grow

to be some of the tallest in the world.

It's a unique relationship between the ocean and the forest...

..that lies at the heart of all life on Vancouver Island.

As autumn takes hold,

stormy weather along the outer coast begins again.

Waves crashing onto the exposed shore

mean new opportunities.

It gives the father wolf a much better chance

of hitting the jackpot.

The summer has been a lean time for his family.

But today, his luck is in.

A massive sperm whale carcass,

a deep-sea species,

that a storm has blown onto the island's shore.

This is his first big meal in weeks.

The rest of the pack is not far behind.

There is plenty of food to go around.

40,000 kilos of protein and fat

will last them for months.

The mother wolf is bringing home takeaway tonight.

The pups are going to have lots to eat now.

(PUPS YAPPING)

As autumn turns into winter,

the weather out here will continue to get worse.

Good news for the wolves.

Gifts on the island's shoreline are going to be more frequent now.

And under the watchful eye of their father...

..the pups will have the best chance to survive their first year of life

on the island.

From the outer coast and inlets...

..to the mountaintops,

from the ancient forest...

to fresh water...

the relationship between land and sea

lies at the heart of Vancouver Island's richness

and diversity,

filling it with life,

making it one of the most extraordinary islands

on the planet.

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