PLANET EARTH - 'Great Salmon Run'
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PLANET EARTH - ‘Great Salmon Run’
Screen Visual Description Narration
The power of the sun drives the
Clouds moving seasons, transforming our planet.
And in a few special places these
seasonal changes create some of the
greatest wildlife spectacles on Earth.
Here on the western coast of North
Satellite view of America, in the spring of each year,
Western N.A. one of the Earth's greatest travelers
followed by shots of comes home.
salmon and bears
Over half a billion salmon leave the
Pacific ocean on a 5000 kilometre
journey, returning to spawn in the
rivers where they were born.
Traveling deep into the continent, these
fish will not only provide food for
millions of animals...
...They will also bring life to one of the
richest habitats on Earth.
The coast of British Colombia and
Alaska is rimmed by spectacular
mountains
Panning of
mountains
TITLE – THE GREAT Although it will be months before the
SALMON RUN salmon enter the rivers below these
frozen peaks, one species that has
spent the winter sleeping up here is
already anticipating their return.
Snug in their dens the females have
given birth, and now the family is
beginning to stir. Grizzly bears.
Shots of three
Whether the cubs will live or die
grizzly bears
depends largely on one key event...the
climbing on the
salmon run.
snow
To find food mothers must lead their
cubs down to the coast, where the
snow will already be melting.
Ultimately, the fate of these bear
Salmon swimming families depends on the salmon.
And right now, those salmon are more
than 3000 kilometres away.
After four years at sea half a billion
Pacific salmon are going home, to lay
their eggs in the rivers where they
themselves were hatched.
Grizzly bears in In May grizzly bears come down to the
grass fields and coast to find something to eat while
walking through a they await the arrival of the salmon.
river
The cubs, still feeding on nothing but
their mother's milk have grown
considerably.
After two months of travelling across
the open ocean the salmon reach the
Salmon swimming coast.
As they detect the waters of home,
they converge into the narrow fiords
which act as underwater corridors.
But other creatures also know these
corridors.
Separate shots of Killer whales...they eat a lot of salmon.
killer whales, sea
lions, a salmon And so do Stellar sea lions.
shark and bald
eagles Salmon sharks are here too.
But there is one predator that they can
never see coming....the bald headed
eagle.
No sooner do they start then they're
View of a waterfall faced with another challenge.
followed by close up
shots of salmon But six million years of evolution have
jumping up prepared the salmon well.
waterfalls
Their bodies are solid muscle and
perfectly streamlined.
Clearing these falls for a salmon is like
a human being jumping over a four
storey building.
In many of these falls however, the
Grizzly bears trying
salmon face more than just water.
to catch salmon
jumping up the river
The bears know that this is where they
can get the first proper meal of the
season.
There is an art to catching a leaping
salmon.
And this young bear hasn't yet acquired
it.
They're driven to get up these rivers to
their spawning grounds.
Their parents made it up here and
nothing short of death will stop them
from repeating that journey.
They're trying to get to the exact
stretch of gravel where they hatched.
Some are faced with a truly daunting
journey.
Shots of mountain
scenes The farthest that salmon have been
known to swim upriver is three
thousand kilometres.
But that doesn't mean there will be no
further problem in reaching the
spawning grounds.
This is going to be the end of the road
for a lot of salmon.
Many grizzly bears
in a stream.
These bears are really hungry. They
Followed by grizzly
haven't tasted salmon for ten months
bears fighting and
and males battle for the best fishing
then trying to catch
spots.
salmon.
The salmon make short, exploratory
leaps to see where the bears are.
But they don't always get it right.
This mother bear has been waiting
months for this moment.
Eventually, they [shot of salmon] have
to go for it, regardless of the danger.
But numbers are on their side. For
every salmon that gets caught,
hundreds make it past the bears.
By early September the salmon have
Shot of a river almost reached their spawning
grounds, that one particular patch of
gravel where they hatched four years
ago.
The sockeye salmon's brilliant colour
signals that they're ready to breed.
Salmon spawning
The female digs out a shallow scoop as
a nest.
When she's ready she lowers herself
over the nest.
She begins to turn out her eggs and
the male releases a cloud of sperm into
the water.
These salmon are the lottery
winners...the lucky ones that have
succeeded in returning here to spawn.
All their trials and tribulations have
ensured that the baby salmon, when
they emerge from these beautiful
orange globes, will have everything
they need to begin this incredible
journey all over again.
Their bodies have been deteriorating
Salmon withering for weeks, and with this last act of
away reproduction they are finally spent.
The mother and her cubs will continue
to fatten themselves on the carcasses
until they're ready to head back up the
mountain to den in November.
There are more than 200 species in the
Salmon being eaten great forest alone...plants and insects,
by crows, eagles birds and mammals that depend on the
and wolves salmon.
It's possible that Pacific salmon,
between their time out at sea and their
time inland, feed more life than any
other animal species on the planet.
And no animal relies on them more
than the grizzly bear.
Thanks in large part to the abundance
of the salmon run; these cubs have
survived their first and most difficult
Grizzly bear and her year.
two cubs
The bears will sleep easy each winter,
as long as the Pacific salmon are able
to continue their epic run...one of
nature`s great events.
END
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