Original subtitles

(BIRDS CHIRPING)

NARRATOR: In America's temperate Northwest...

...shrouded by forests...

...and encircled by high peaks...

...lies a tidal arena of glacial streams,

salt marshes

and shorelines.

The animals that survive here

are hardened to the elements.

Half-tonne predators...

...fierce aerial fighters... (EAGLES SCREECHING)

...and small, but mighty hunters.

They are resourceful opportunists,

adapted to endure this wintery wilderness,

and, when spring arrives...

...they go into overdrive.

(GROWLING)

They fight to rule the sky... (EAGLES SCREECHING)

...and wrestle to assert their dominance.

(ROARING)

and use their cunning

to capitalize on a narrow window of available food.

Opportunities are fleeting.

(GROWLING)

So, as the clock runs down

on this time of plenty,

it's do...

...or die.

(DRAMATIC MUSIC)

After six months of brutal cold...

...America's Northwest coast is bathed in warm, spring sun.

It's awoken one of the elders of this arena.

(BEAR HUFFS)

Brown Bear.

He survived the winter, hibernating in his mountain den.

He made the journey down into the tidelands a week ago...

...and his metabolism is ramping up.

Over winter, he lost a third of his body weight.

He's starving...

...and he's on a mission to feed.

He needs to make the most of these warmer months,

and bulk up before the cold returns.

(CRUNCHING)

The best food for him, after his long hibernation,

is sedge grass.

It's packed with protein.

So, this lush meadow is his lifeline.

But the grass is just an appetizer.

Later in the season,

the stream running through it will be teeming with salmon.

(GRUNTING)

(CRUNCHING GRASS)

But keeping this feeding spot for himself...

...won't be straightforward.

Other bears are waking from their sleep...

...all looking for a place to feed.

(TENSE MUSIC)

This time of year isn't just about eating.

It's the time to reestablish hierarchy

for the rest of the season.

A large male is heading for Brown Bear's patch.

(TENSE MUSIC CONTINUES)

Brown Bear must eat 14 kilos of grass each day,

to gain the weight he needs.

Fighting, when he's this low on energy,

isn't the smart thing to do.

(INTRUDER GROWLING)

He recognizes the outsider's scent,

a male he's encountered before.

Brown Bear has learned to read the subtle posture changes,

that can reveal a rival's hand.

(INTRUDER GROWLS SOFTLY) And he knows...

...his opponent, is agitated.

(OMINOUS MUSIC)

(GROWLING)

Brown Bear tries to settle him with a stern paw.

An all-out brawl could see both bears getting gravely injured.

He turns his body side on,

signalling that he's not looking for a fight.

But the outsider wants to escalate.

(INTRUDER ROARS)

He senses an opportunity to advance up the social hierarchy.

(BOTH ROARING)

He grapples Brown Bear with his claws and teeth,

a clear attempt to establish dominance.

His loose pelt makes it hard for the challenger to keep hold him.

He lands a bite on Brown Bear's ear,

with enough force to crack a bowling ball.

(ROARING)

(ROARING CONTINUES)

It's too much for Brown Bear to take.

Experience tells him,

that he doesn't need to meet every dominance battle head on.

Risking injury so early in the season, isn't smart.

So, he backs away... for now.

(BROWN BEAR PANTING)

(BROWN BEAR HUFFS)

Brown Bear has to concede

a prime spot in this riverside meadow.

He must now use his wisdom and experience

to stake his claim on a new feeding spot elsewhere.

(TRANQUIL MUSIC)

As the spring sun warms this arena...

...creatures of all kinds are emerging...

...to cash in on the improving conditions.

(CHIRPING)

Soaring over them all...

...Bald Eagle.

She spent the winter further south...

...where the lakes remained ice-free.

Now she's back to make the most of the spring weather,

that, each year, turns this bay

into a rich fishing territory.

(BIRDS CHIRPING)

For the past twelve seasons,

she's successfully staked her claim here.

Her four-square-kilometre territory

is not just important for food...

...but also...

...for continuing her bloodline.

(CHICKS CHEEPING)

Sitting 50 metres up in a Douglas fir...

(LOUD CHIRPING)

...is the large nest she first built with her lifelong partner

over a decade ago.

Each year, the pair return to raise a new brood of chicks.

And this year's eight-week-old youngster, is growing fast.

With an extra mouth to feed,

protecting her territory is of the utmost importance.

And this season, an invader has arrived early.

(OMINOUS MUSIC)

A juvenile bald eagle...

...probing the area to see if she can fish here.

This confident outsider, is clearly trying its luck.

(SCREECHING ECHOES)

Bald Eagle's high-pitched territorial call is her war cry.

It reverberates across the bay, warning the intruder.

But the youngster isn't deterred.

(TENSE MUSIC)

Bald Eagle's 7,000 feathers work in unison,

producing maximum lift

with flawless aerial control.

(SCREECHES)

The juvenile's wing and tail feathers,

are longer than an adult's.

They're better suited for slow soaring.

(SCREECHES)

But Bald Eagle's shorter feathers produce less resistance,

allowing her to flap faster

and fly with greater speed.

(SCREECHING)

Using its tail as an airbrake,

the juvenile wheels around to get behind her.

To minimize drag,

the juvenile spreads its wing tips wide

then turns for the attack.

(SCREECHING)

Bald Eagle splays her taloned feet

to lock onto the youngster.

By folding back her wings, she forces it downwards.

(SCREECHING)

The juvenile's feathers aren't waterproof.

A sitting duck.

(TENSE, OMINOUS MUSIC)

Bald Eagle drops into a highspeed dive...

...and goes for the strike.

She aims eight needle-sharp talons at her target.

The juvenile twists to avoid being impaled...

...and only narrowly escapes injury.

The juvenile gets escorted out of the bay...

...leaving Bald Eagle in peace...

...to secure her next meal.

The price for presiding over this prime fishing spot

is a daily battle against opportunists.

As spring progresses,

competition will only get more intense.

The tidelands are about to undergo a dramatic transformation...

...inviting a host of new opponents into this arena.

At high tide, deep water covers the tidal flats.

Below the waterline...

...new arrivals are moving in.

This is a toadfish.

Each year, the spring conditions

lure millions of them to spawn along the coast.

Right now, the toadfish is safely hidden underwater.

But in the coming days,

this shore will undergo a dramatic change...

...exposing a seafood feast...

...that will attract predators of all kinds.

Bald Eagle must be ready to fight.

While the fate of the animals above the waterline

hangs in the balance...

...in the freshwater stream that feeds the estuary...

...there's another small, but deadly creature

preparing for a battle of its own.

Dragonfly nymph.

A five-centimetre-long, aquatic hunter.

She survived the winter by burying herself in the sediment.

By entering a state of suspended animation,

she was able to withstand the freezing temperatures.

But now she's out,

she's ready to feed.

Her strategy?

The ambush.

Each of her huge eyes is made of 30,000 parts.

80% of her brain is dedicated to processing vision...

...giving her a 360-degree view of her world.

(TENSE, OMINOUS MUSIC)

She strikes her prey with her pincers

in ten milliseconds,

and drags it towards her mouth.

(CRACKLING SOUND)

This beetle releases a foultasting chemical.

Nymph opts to find a more palatable meal.

Luckily, the spring conditions have delivered

a bounty of newly-hatched fish.

(OMINOUS MUSIC)

The powerful grasp of Nymph's serrated jaws

makes it impossible for the fish to shake free.

Only the most powerful of insects can hunt vertebrates.

Her paired mouth parts grind together

to slice through the flesh and bone.

(CRUNCHING)

She cleans her weaponry,

ready for the next meal.

She must make the most of the springtime riches...

...because this year is Nymph's most critical yet.

She's lived in this stream for four years,

and if she can make it to summer,

she'll shed her skin

and emerge into a fully-winged adult dragonfly.

But to survive, she must be on her guard...

...ready to take on an age-old foe.

Surviving the tidelands

isn't just about powerful jaws and brute strength.

Great Blue Heron's tactic

is to slip beneath the radar.

(SUSPENSEFUL MUSIC)

He's a one- metre-tall sneak thief,

creeping on stilt-like legs,

scanning the landscape

with his powerful, binocular vision.

90 percent of his waking time is spent hunting.

In the still water, he moves meticulously,

without a ripple.

He then waits, motionless,

for any prey to wander close.

The fish in these slow-moving streams are just small fry.

Soon, a rare tide will offer up a bigger prize.

The only snag?

That fishing spot is closely guarded.

(TENSE, OMINOUS MUSIC)

Bald Eagle's territory.

Poaching fish from a territorial raptor,

will be a high-stakes game.

(EAGLE SCREECHES)

Finally, the moment has come.

The tidelands begin their dramatic transformation.

(SUSPENSEFUL MUSIC)

As water drains from the estuary,

the tide starts to fall.

But a few times a year, the tides here get supercharged.

When a full or new moon passes close to Earth...

...its gravitational pull is amplified.

The perigean spring tide.

The water level drops many metres below normal...

...exposing a one-and-a-half kilometre stretch of oyster beds.

Thousands of toadfish

are stranded and exposed

across this vast, tidal expanse.

(SUSPENSEFUL MUSIC)

From the forests behind the beach...

...Heron makes his advance towards the oyster beds.

Bald Eagle's long-distance vision

is eight times better than ours.

She could spot a rabbit at three kilometres.

If Heron is spotted in her territory,

he could be attacked, even killed.

He pauses to scan the exposed tidal flat for dangers.

These extreme low tides will only last a few days.

To capitalize on the optimum fishing window,

he needs to move now.

(SUSPENSEFUL MUSIC)

(MUSIC INTENSIFIES)

The exposed oysters are razor sharp.

But Heron's long toes act like snowshoes,

spreading his weight.

His large eyes have a built-in zoom lens.

He switches between telescopic and closeup vision

to find the fish caught in the tidal pools.

A meaty toadfish.

To defend itself, it extends its spiky dorsal fin.

So Heron uses his beak as a spear,

to sever its spinal cord.

The activity hasn't gone unnoticed.

With her nest nearby,

Bald Eagle has a zero-tolerance, no-fishing policy.

But Heron is just getting started.

His large stomach can expand to hold half his bodyweight in fish.

(EAGLE SCREECHES)

Bald Eagle's counter strike kicks into gear.

(TENSE MUSIC)

Soaring 100 metres above the bay...

...her keen eyesight allows her to calculate

her exact angle of attack.

She tucks her wing and dives at a speed

close to 160 kilometres an hour.

(HIGH-PITCHED CAWING)

Only now, does Heron clock the incoming attack.

There's no time to swallow his catch.

(TENSE MUSIC CONTINUES)

(HERON SQUAWKS)

He throws his wings wide and wields his sharp beak.

(HERON SQUAWKS)

Eagle twists to dodge it

and delivers a devastating body slam.

Heron recovers to reclaim his fish...

...and a mouthful of seaweed.

Bald Eagle is three times faster than Heron.

But Heron is lightweight,

with superior endurance.

With his two-metre wingspan,

he banks steeply, dodging the attack.

(DRAMATIC MUSIC)

Heron's heavy payload of fish is slowing him down.

He can no longer keep hold of his pirated meal.

Heron flees to the outer fringes of the bay...

...but Bald Eagle's problems are just beginning.

The extreme low tides have drawn all comers from across the region.

(HIGH-PITCHED CAWING)

Adults and juvenile eagles from many kilometres away are arriving,

hoping to fish here.

(EAGLE SCREECHING)

And more great blue herons are arriving, too.

Her territory has become overrun.

And the outsider eagles are trying to assert their dominance

at this lowtide feast. (EAGLES SCREECHING)

(SCREECHES)

(HIGH-PITCHED CAWING)

(TENSE MUSIC)

(HIGH-PITCHED CAWING) With her nest nearby,

Bald Eagle doesn't take kindly to trespassers.

To reassert her rule,

she must deliver a powerful show of strength.

She fixes her sights on a large adult female with a beakful.

(DRAMATIC MUSIC)

Her target takes flight with the spoils...

(HIGH-PITCHED CAWING)

...but Bald Eagle can't let her get away.

The rival skillfully guards her catch

with a mid-air barrel roll.

Bald Eagle picks her moment and goes all in...

...sending her opponent into a spin,

forcing it to drop the meal.

But the rival has travelled hundreds of kilometres

for the chance to fish in this prime territory.

She's prepared to fight.

Bald Eagle locks onto her,

dragging her to the ground.

(HIGH-PITCHED CAWING)

Then, she circles back, and rushes the rival.

(EAGLES SCREECHING)

Bearing her powerful, crushing talons...

...the challenger is outmaneuvered and outdone.

She flees.

While the eagles have been squabbling...

(BIRDS CAWING)

...the bay has descended into chaos.

(BIRDS CAWING)

(CAWS)

And a familiar foe is taking full advantage.

Heron.

He's caught enough toadfish to sustain him for days.

Stuffed with a kilo of food...

...he returns to the cover of the forests.

(HIGH-PITCHED CAWING)

Only when the tide turns,

will calm return to Bald Eagle's beach.

(HIGH-PITCHED CAWING)

Along the coast,

Brown Bear is working the extreme low tide to his advantage.

(BEAR HUFFING)

Following his nose,

he locates a hidden treasure.

Clams.

Brown Bear's ten-centimetre-long hooked claws

aren't just for fighting.

They're tin openers.

It's a skill that only the smartest bears have mastered.

Brown Bear shucks enough to take the edge off his hunger.

But clams are a labour-intensive food.

And a more enticing smell is in the air.

(SNIFFING)

With his face to the wind,

Brown Bear follows his nose.

(SNIFFING, HUFFING)

His sense of smell is seven times more sensitive

than a bloodhound's.

(SNIFFING)

The part of his brain that identifies smells,

is five times bigger than a human's.

And now, it's picked up the trail of something

that could be the find of the season.

(BIRDS CHIRPING)

In the stream above the estuary...

...Dragonfly Nymph is edging closer

to the day she can fly away.

But in this arena,

nothing is guaranteed.

(MENACING MUSIC)

Lurking in the weeds, another monster.

Giant Waterbug.

At six centimetres long,

he's one of the largest aquatic insects on Earth.

Twice as big as Nymph...

...and her biggest obstacle to reaching adulthood.

He can take down prey many times his size.

He'll even eat his own young.

(BIRDS CHIRPING)

Fine hairs on Nymph's legs,

sense subtle changes in the underwater currents.

They alert her to something large nearby.

A potential meal?

Curiosity lures her closer.

(TENSE MUSIC)

Around a rock...

...the mystery creature becomes apparent.

They each see the other as prey.

Nymph makes the first move.

But she's too close for her pincers to be effective...

...and Waterbug drags her underneath him, to pin her.

Nymph twists,

allowing her to break free.

Her tail end works like a jet ski...

...forcing out a pressured stream of water

to propel her forwards.

More agile? Maybe.

But Waterbug is stronger.

He pins her a second time,

and tries to use his needle-like beak

to inject her with digestive saliva.

Nymph's exoskeleton is covered in a tough armour plating.

Waterbug searches for any soft spot to insert his beak.

Nymph, is unable to wrestle free,

but there's a lifeline.

She can breathe underwater through gills in her abdomen.

Waterbug is an air breather.

The battle is sapping his oxygen.

If Nymph can keep up the fight,

Waterbug will be forced to break for the surface.

He adjusts his body to reach up.

It's all Nymph needs to break free.

Deploying a snorkel from his rear...

...Waterbug breathes in as fast as he can.

He traps air under his wings like a scuba tank.

Then races to find Nymph.

But he's too slow.

Nymph's camouflage, is like a cloak of invisibility.

She disappears into the murk.

She's now one day closer to gaining her wings.

Waterbug, must continue his hungry hunt.

Brown Bear, has followed the alluring scent trail.

A whale, washed up in a recent storm.

20 tonnes of highly calorific meat.

It's a goldmine.

(FLIES BUZZING)

But there's a catch.

Someone else has discovered it, too.

A large male...

...and two females...

...enjoying the feast of a lifetime.

The male tolerate females sharing the carcass with him...

...as they aren't a threat to his place in the hierarchy.

There's a high chance they'll allow him

to mate with them, too.

(HUFFING)

If Brown Bear wants a place at this table,

he must fight for it.

Ears forward and mouth open...

(GROWLS)

...he makes his intentions clear.

This time, he's ready for an all-out brawl.

(GROWLING)

The females sense they won't be able to eat in peace

and move off.

But the big male, stands firm.

(HUFFING)

(GROWLS)

(TENSE MUSIC)

(ROARING)

Each bear weighs over 450 kilos.

(ROARING CONTINUES)

Their front legs are the strongest of any predator.

And their jaws are capable of killing bison and wolves.

But taking on one of their own kind is a different story.

Brown Bear, in the left corner, senses they're an even match.

(HUFFING, GROWLING)

To assert his dominance,

he must convince the opponent that he's tougher.

The opponent rises on his hind legs,

to over two-and-a-half metres tall.

But he can't keep a footing amongst the boulders.

Brown Bear swipes at his legs,

trying to knock him off balance. (ROARING)

The challenger is wrongfooted.

And Brown Bear pushes him back into the water.

(ROARING CONTINUES)

Dominance fights like this are won by wearing down the opposition.

It's a drawn-out wrestling match,

with each bear trying to tire the other into submission.

Brown Bear's relentless biting and pawing

is overwhelming his competition...

...slowly exhausting him.

His rival is outbattled and drained of energy.

While the defeated male nurses his wounds...

...Brown Bear tucks into his 20-ton prize of whale meat.

The blubber alone, contains some 8,000 calories per kilo.

He'll gain close to three kilos with each sitting...

...ensuring he'll be sufficiently fat to survive the next winter.

(BEAR GROWLS) (WOLF SNARLS)

The wolves will have to make do with the scraps.

Brown Bear's successful display of dominance

hasn't gone unnoticed.

A female has returned to show her interest.

And with the competition now long gone,

these two can be left in peace.

(EAGLE CALLING)

All across the tidelands...

...the good weather has delivered on its promise.

Under the golden sun

daring strategies have allowed the boldest,

and the bravest, to reap great rewards.

Once more, calm has returned to the tidal flats.

And new chapters are being written.

These animals have won their battles,

and their prize?

To live another day...

(TRIUMPHANT MUSIC)

...and survive another winter...

...in America's wild tidelands.

(BROODING THEME MUSIC)