Oceans (Full Episode) | Hostile Planet

three days of digging

and this olive ridley turtle

is free

but not safe

until she gets to the sea

where early life evolved

and where nearly 80 percent of animals

still

live of all the hatchlings born this

year on the costa rican coast

only 10

will make it

now she's in her element

but her journey has just begun

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in 10 years time she will return to

these shores to lay eggs of her own

if she survives

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the ocean is a fluid and unpredictable

world

and all those that live here

are at its mercy

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our planet's oceans cover 70 of its

surface

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and provide an incredible 99

of his habitable space

this may be an alien world to us

but it's home to an extraordinary range

of animals

from the biggest

to the strangest creatures in our world

even for the most marine adapted

life isn't easy

survival at sea

is a completely different game

to survival on land

especially

when the rules keep changing

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where the atlantic and indian oceans

meet

new conflicts between old foes are

brewing

rising sea temperatures are pushing fish

eastward to cooler waters

those that feed on them have followed

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fur seals

their new home is treacherous

and it's not just the waves

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it's what lies beneath

not the best place

to learn to swim

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but the perfect hunting ground for a

great white shark

this pump has strayed too close to the

edge

now it's out of its depth

a puck can outmaneuver a shark

but only for so long

half of all such encounters end badly

for seals

the adults must deal with this

persistent menace

but how

it takes one brave seal to lead the way

so

others join

soon they are a mob

harassing the intruder

it's a risky strategy

sharks can turn on a dime

together they've overcome a giant

the pups are safe

at least for now

shallow continental seas are the most

productive waters in our oceans

they're also some of the most

competitive

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during winter

these freezing fields are the stage for

one of the biggest wildlife spectacles

on the planet

this orca pod comes here every

year they're led by a matriarch

she could be 70 years old

for a pot that specializes in hunting

fish

this is an unmissable event

herring

billions of them

more fish here than people on the planet

but the bigger the show

the harder it is to single out a target

the orca need to come at the problem

from another angle

coordinating their attack

they divide and conquer

herders work to split the shoal

then in come the big hitters

their tails creating a shock wave

stunning up to 30 fish with each blow

they must work quickly

they're not the only hunters here

humpbacks

six times the weight of an orca

they can devour more than 200 pounds of

herring in one gulp

the orca simply can't compete

but they can switch tactic

as long as they're prepared to face down

the most dangerous predator in the ocean

in the ocean where there is food

there's usually a fight

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off the fields of norway

these orca are about to take on the most

aggressive ocean hunters of all

us

fishing boats like this can scoop up 800

tons of herring a day

out fishing orca and humpbacks combined

desperation has forced these orca

to turn this new obstacle into

opportunity

off the fish that slipped through their

competitors

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recently imposed quotas ensure there are

enough herring for humans and whales

but the global picture isn't so bright

we are consuming more fish than ever

before

reducing many stocks to little more than

scales

unbalanced oceans are open to invasion

by strange life forms

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they start life as pinhead sized polyps

but what they lack in size

they make up for in numbers

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gorging on tiny plankton

they grow

mutate

and multiply

into an army of clones

now each polyp becomes a production line

with one purpose

creating new jellyfish

bodies that are 95 water can easily grow

and grow

until they are monsters

no bones

no blood or even brains

but perfectly suited to today's

transforming seas

resistant to increasing temperature

decreasing oxygen

changing salinity

rising acidity

even plastic pollution

when a jellyfish swarm takes over

some ecosystems never fully recover

our impact also extends to the biggest

marine habitat of all

the open ocean

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it covers more than half the globe

the food here is increasingly scarce

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yet one animal perseveres

despite needing one and a half million

calories every day

the blue whale

the largest animal ever to have lived

she's as long as an 18-wheeler

with a heart as big as a car

and a ton that weighs as much as an

elephant

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just this year she swum far enough

to have circumnavigated the globe

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all in search

of this

krill

one of the most important species in the

marine food chain

with each monumental gulp

she takes in enough water and krill

to fill the school bus

her tongue forces the water back out

through the bristly plates on her jaw

trapping up to two million krill

blue whales were hunted to the brink of

extinction although they're still in

danger

since a ban on whaling in the 1960s

their numbers have increased worldwide

and here

off the coast of california

they've almost completely recovered

the vast open ocean

can be a lonely place

this green turtle has spent 30 years out

here on her own

somehow she's found enough food to

survive and grow

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now she's ready to return home

but it will be a dangerous journey

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it's the breeding season

and hundreds of turtles are gathering to

try and win a partner

males mate about four times as often as

females

so she attracts a lot of interest

this male is quick to latch on

[Applause]

but the others won't give up without a

fight

off the coast of malaysia

it's green turtle breeding season

this female has found a mate

but other males are intent on splitting

the pair

targeting the male soft flesh

they tried to force him to let go

but the female has the most to lose

the fiercer the pursuit

the more oxygen she burns

the stressed turtle can drown in minutes

she's desperate to reach a surface and

breathe

but one challenger just won't give up

the female is running on empty

finally the intruder backs off just long

enough

she's safe

but in just a few weeks she will face

the final hurdle in her epic struggle to

continue her line

where the tropical sun meets the shallow

seas

you find the busiest ocean habitat of

all

coral reefs

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they account for less than a thousandth

of the sea floor

but a home to a quarter of all marine

species

in this crowded and dangerous place

finding shelter is essential

some hide in the coral maze

others seek sanctuary in the shop

but neither tactic guarantees safety

lionfish are one of the most efficient

killers on the reef

yet there is a far greater threat facing

all those who live here

our seas have been steadily warming for

the past 75 years

now it's happening faster than ever

before

it's having a profound impact on life

throughout our oceans

coral reefs are particularly vulnerable

just a three degree temperature rise

it's too much for coral

it forces them to expel the algae that

feed them

and give them their colour

this bleaching is a first step towards

an almost irreversible demise

unless temperatures drop

the reef becomes a wasteland

in three decades we've lost over a

quarter of the world's corals

home to around 4 000 species of fish

if warming continues

we could lose the rest

even those that live far below aren't

safe from rising ocean temperatures

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opalescent squid

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in the past few years warming seas

disrupted their mating habits

and the numbers have fallen dramatically

but this year an influx of cold water

has revived their breeding ritual

a trip to the shallows to mate

by moonlight

males grab the females and fertilize

their eggs

which are then deposited on the sea

floor

it's a brief and brutal affair

within days of mating they will all die

but their legacy lives on

each capsule contains up to 300 new

lives

one successful breeding season can go a

long way towards reversing their recent

bad fortunes

those still alive retreat back to a

place beyond the reach of the sun

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where crushing pressures have morphed

bodies

into the stuff of nightmares

[Applause]

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to reach one of the most hostile

environments on earth

you must descend thousands of feet

beyond the sun's reach

down into the ocean's depths

the pressure here would crush you like a

soda can

there is life

just not as we know it

75 of animals make their own

light eyes are supersized

to catch what tiny luminescence there is

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and soft bodies dominate

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in this vast abyssal wilderness

one of the toughest trials

is finding a mate

anglerfish have a grizzly solution

this giant female's tiny hangar on is a

male anglerfish

many males never find a mate

those that do

never let go

his mouth fuses with her very tissue

his only nourishment her blood

bonded

for life

this alien environment is full of

surprises

it even snows down here

of organic matter fall for weeks towards

the sea floor

along the way they fuel an ecosystem of

microscopic animals

and graceful giants

the stygio medusa jellyfish

its ribbon-like arms extend up to 30

feet to absorb tiny plaque tonic

creatures

also we believe

even today the lives of these deep sea

monsters remain shrouded in mystery

but the biggest surprise of all

this marine underworld is one of the

most stable habitats on the planet

out of touch with what's happening far

above

the sun has fueled a monster

it heats surface waters until they

evaporate

and build into oceanic storms that

render humans powerless

and when conditions are just right they

grow into one of the most formidable

forces on the planet

hurricanes

they form over tropical seas then their

devastation spreads

they release so much energy that just

one could power our entire planet for a

week

and as global temperatures rise

hurricanes are growing stronger

this is the calm before the storm

most people were already taking shelter

but just offshore

others are on the move

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mullet

in their millions

few have heard of it but this is one of

the largest gatherings of any animal in

the united states

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the mullets need to reach their spawning

grounds further south before

temperatures drop too low

such a massive fish in the sea

doesn't go unnoticed

expert hunters attacked the shoal from

every angle

below are the tarpon and blacktip sharks

above

pelicans

and osprey

as the waves are whipped up by the

approaching storm

the pendulum swings in the mullet's

favor

in the turbulent shallow water

they're harder to target

finally the swells grow too powerful

as the storm makes landfall

along the coast

ocean storms create some of nature's

most awe-inspiring wonders

nazarene in portugal sees some of the

biggest waves in the world

towering as high as 10 stories

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but the stormier our seas become

the more those living on the coast to

suffer

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an island on the edge of existence

home to rockhopper payments

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a dense layer of fat gives them some

protection

still

they take a battering

this mother can't back out now

a chick needs food

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and it's dad's turn to hold the fort

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life in the colony is tough

declining fish stocks and rougher seas

have made food harder to combine

and what was already a rough sea

is about to get a whole lot rougher

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the most powerful storm in almost 30

years is closing in

worse than anything these penguins have

faced before

on the far south of the globe

a brutal storm is finally subsiding

but for these rock hopper penguins the

waves are still deadly

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the latest shift of hunters returns

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but this chick's mom

is nowhere to be seen

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then

she appears

amongst the last stragglers

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home and dry

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so

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in just 12 hours

she'll return to

once more

right from the very beginning the ocean

has been a cradle of life on our planet

the many creatures that still live here

are really a legacy of that

irrepressible will

to succeed in a turbulent world

no matter what the ocean has thrown at

them

somehow

they've managed to endure

against near impossible odds

this mum-to-be has found her way back

to the beach where she was born

it's the first time she's been on land

since hatching over a decade ago

and she's not alone

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hundreds of thousands of female olive

ridley turtles

are returning to the costa rican

coastline to lay their eggs

a cycle of life sustained by the sea for

30 million years

never has the journey been harder

yet so far

these turtles are still holding on

in these fast changing times

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