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There is a force sufficiently
powerful to move the oceans

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of this world.

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It is a force not of this Earth.

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The Moon is large enough
to generate gravity

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and with sufficient force to pull
on the Earth 230,000 miles away.

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As the Moon orbits the Earth,

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its gravity sweeps across
the face of our planet.

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Its power drags a great bulge
of oceanic water in its wake...

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..the rising tide.

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The River Amazon in Brazil.

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On some special days,
the gravitational forces

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of the Moon and the sun combine,
to extraordinary effect.

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A growing tidal wave from the ocean
is being forced 200 miles inland.

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This is a tidal bore.

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Fortunately, tidal bores are rare,

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but the Moon does create strong tides
out in the world's oceans

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on every day of the year.

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The Bay of Fundy in Nova Scotia.

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The tides here
are the largest in the world,

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and have a profound effect
on marine life,

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creating a rich feeding ground.

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A feast that attracts some
of the largest diners on the planet...

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..humpback whales.

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But they are not the biggest threat
to the herring.

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These are finback whales.

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At 70 tonnes, they are the second
largest animal on Earth,

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but so streamlined they are
the fastest of the great whales.

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This combination of speed
and immense size

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makes the finback a voracious hunter
of schooling fish.

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The Bay of Fundy
can attract so many fish

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that, during the summer,

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as many as 500 of these magnificent
whales hunt here every day.

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The feeding is best
where the tides run strongly.

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So the whales
move further into the bay,

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following tidal rips
and searching for fish.

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Their movements are closely watched
by flocks of Cory shearwaters.

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As the whales dive down towards
the fish, more and more birds gather,

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anxious to pick up scraps.

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The flowing tide

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may provide a feast,
but, before long, it will turn.

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In just six hours,
100 billion tonnes of water

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will flow out of the bay,

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the sea level falling
by as much as 15 metres

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and exposing vast tracts
of mud and sand.

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At first sight, a barren place,
entirely devoid of life.

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In fact, the damp sand
is packed with microscopic life,

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the meiofauna,
feeding in a sandy underworld,

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quite unaffected
by the departure of the sea.

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But life is not all roses
in this miniature world.

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A sand bubbler crab
in Northern Australia.

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It hunts meiofauna.

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Just a centimetre across,

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the sand bubbler
works at breakneck speed,

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filtering out the meiofauna
and kicking aside the waste.

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The crab will clean

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every grain of sand
within a metre of its burrow.

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Endless practice for the best
backheel in the natural world.

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The crabs work fast

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because they can only sieve
when the sand is damp.

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Remarkably, they work
the entire surface of the beach

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within a couple of hours
of the tide retreating.

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Then they simply return to their
burrows and await the next tide.

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Underwater,
the falling tide is the cue

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for some bizarre activity.

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These slow—moving clams
use their muscular feet

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to bury themselves under the sand.

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If they fail to get under cover,

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the tide will leave them exposed
to the air and they will perish.

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But once underground,
they can wait,

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safe beneath the beach,

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And not a moment too soon.

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June in south east Alaska.

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In just four hours, a vast beach
is exposed by the falling tide.

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The bears are hungry.

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At this time of year, the pickings
on land are few and far between.

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But any food here has long since
buried itself deep under the sand.

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To a hungry adult bear,
that is no barrier.

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They smell the clams through
the sand and simply dig them out.

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For such large animals,

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they show
quite extraordinary dexterity

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at opening
the unfortunate shellfish.

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Cubs try their luck, too,
none too successfully.

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But for the adults,
the shellfish feast

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lasts as long
as the tide remains out.

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Table Mountain in South Africa.

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Every day, the retreating waves
leave flotsam on the beach.

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And this creature
is scenting the currents

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for the odour of rotting fish.

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The tide carries the scent
far into the surf zone.

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Responding to the smell,
snails emerge from the sand.

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This is a race against the tide.

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The snails need to find their meal

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before the tide
leaves it beyond reach.

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But snails are slow
and the tides fall rapidly.

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These, however,
are no ordinary snails.

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They can surf!

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They ride the waves up the beach

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but, all too soon, the tide leaves
the fish beyond the surf zone.

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Without the sea, there's a danger
the snails will lose the scent,

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but as long
as the sand remains damp,

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they can still follow
a faint trail to the food.

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Once there,

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they tuck in with macabre relish.

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Good things come to those who wait.

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Soon, the heat of the sun
forces them to retreat into the sand

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to await the return
of the next tide.

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February in Britain.

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The falling tide is eagerly awaited
by these knot.

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As the water retreats,
countless small invertebrates

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seek shelter under the mud.

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And with good reason.

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Waders are specialists
at probing in the mud,

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their variety of beak shapes

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designed for reaching
different invertebrates —

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keys that unlock the safety
of the tidal flats.

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But within a few hours,
the tide will turn again.

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Soon, the waders
are out of their depth.

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The creatures of the mud
are safe once more.

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Underwater, incoming tides
can create a strong current,

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and flounder are experts
at hitching a tidal lift.

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They are shaped
rather like a kite,

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a perfect design
for gliding on the tide.

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In Newfoundland
on the east coast of Canada,

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large numbers of flounder ride
the currents up into the shallows.

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They've come to hunt invertebrates

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that will emerge
now that the water is back.

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The pickings in the shallows
can be very good.

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The activity
has not gone unnoticed.

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But ospreys can't dive deeply.

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As long as the water is more than
a metre deep, the flounder is safe.

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Going too far inshore

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can be a risky business.

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This fish buries itself
completely in the sand

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at any sign of danger.

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But when the tide floods in again,
as long as the coast is clear,

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these sand lancet will re—emerge.

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After a wait of six hours
under the sand,

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they are desperate for food.

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Unlike flounder,
they head out to sea,

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looking for shallow, open water

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where the tidal currents will
concentrate their food — plankton.

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In untold thousands, they stream
towards the best feeding grounds,

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where they simply pick up

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tiny planktonic creatures
from the water.

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But, if they swim too far off—shore
in search of food,

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they risk meeting large predators
that live in deeper water.

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Dogfish — small sharks.

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The sand lancet have strayed
out of their safe depth.

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The effect of the turning tide

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can be totally different
on a rocky shore.

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Here, on the coast
of Vancouver Island in Canada,

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the sun bakes the exposed rock.

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It's almost impossible to dig
underground when the sea retreats,

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so these mussels and barnacles
are fully exposed to the sun's heat,

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literally cooking
in their own shells.

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And the seaweed
simply dry to a crisp.

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It can be a wait of many hours
before the water returns.

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Throughout each month, the size
and strength of the tide changes.

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The biggest tides of all happen

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when the gravities of the sun
and Moon pull in unison.

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That happens immediately
after the new moon...

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..and again after the full moon.

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These are called the spring tides.

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They revealvast tracts of seabed
that would normally be covered.

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For these racoons, it's a chance
to look for a seafood feast.

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A mother ventures forth
with her kits.

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With the spring tide,
they've come further down

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than smaller tides
would normally allow.

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Searching
with their sensitive paws,

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they look for suitable prey.

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With the extreme low tide,
they could find something special.

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And what could be better
than a red rock crab?

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That is, if it weren't
for the risk of a painful pinch.

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With crabs, there's no substitute
for experience.

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The mother
makes an expert's catch.

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But the kits learn fast.

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And for those that don't,
begging is always worth a try.

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All too soon, the returning tide
will cover the racoon's table.

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For the invertebrates,
it's a welcome relief,

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but in rough weather,
they are exposed

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to the worst of the waves.

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Even when there are no waves,

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the incoming tide can create
considerable forces underwater.

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The gaps between these islands
on the east coast of Vancouver Island

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channel the tidal flow.

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As the tide keeps rising,
gradually the water flows faster,

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and soon these 30—metre—long
bull kelp plants

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bend to the current.

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They are sufficiently flexible
to cope without too much damage,

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but there are some spots where
the currents are especially powerful.

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This is the Nakwakto Rapids.

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00:23:29,840 --> 00:23:35,518
At the turn of the tide, water from
almost 700 miles of coastal fjords

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00:23:35,680 --> 00:23:39,754
will have to empty through a gap
half a mile wide.

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00:23:39,920 --> 00:23:44,870
Within a few minutes, the current
is already picking up speed,

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00:23:45,040 --> 00:23:48,716
until water roars by
at over 17 miles an hour.

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00:24:26,560 --> 00:24:28,552
Tidal currents
are not always damaging.

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00:24:31,240 --> 00:24:34,756
Here, in the Poor Knight Islands
of New Zealand,

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weak tides run through rock arches,
making it an ideal resting place

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00:24:39,960 --> 00:24:41,599
for stingrays.

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00:24:49,680 --> 00:24:55,039
These rays congregate here
in huge numbers every March.

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They've come to breed.

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The arches funnel the current,
which the rays can ride

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with the minimum of effort,
so saving energy.

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Nearby, out in open water,

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00:25:21,480 --> 00:25:25,838
a school of two spotted demoiselle
fish are feeding on plankton,

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00:25:26,000 --> 00:25:31,758
and the current is perfect
for sweeping their food past them.

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00:25:42,800 --> 00:25:46,589
Once the current starts to weaken,

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00:25:46,760 --> 00:25:48,752
there is insufficient food

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to warrant the risks
of swimming out in the open.

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00:25:52,200 --> 00:25:55,830
So, the demoiselles head off
to find shelter en masse.

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Safety is in numbers.

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00:26:07,120 --> 00:26:11,558
More and more demoiselles
pour towards the cave entrances

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00:26:11,720 --> 00:26:14,679
that riddle the Poor Knight Islands.

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00:26:43,240 --> 00:26:46,836
Safe at last. Inside the cave,
they are less exposed

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00:26:47,000 --> 00:26:48,912
to attack from predators.

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00:26:52,320 --> 00:26:55,074
Thousands of demoiselles
and blue mao mao

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00:26:55,240 --> 00:26:59,393
wait for the return of the current,
when, once again,

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00:26:59,560 --> 00:27:02,473
they will head out
into the open to feed.

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00:27:07,280 --> 00:27:10,910
The Moon's gravitational pull
is weaker

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nearer to the Earth's equator.

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00:27:14,120 --> 00:27:18,831
So, the more equatorial the location,
the smaller the tides.

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00:27:19,000 --> 00:27:24,200
Out in the Caribbean Sea,
the tidal movements are slight.

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Even so, they are sufficient

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to push free swimming plankton
in their path.

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These are thimble jellyfish.

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00:27:38,320 --> 00:27:40,232
They swim towards sunlight,

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and invisible boundaries
formed by the tidal motion

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help to herd them together,
until they gather in immense swarms.

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00:27:50,040 --> 00:27:52,919
They put the tropical sunshine
to good use.

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00:27:53,080 --> 00:27:55,311
Their brown colour comes from algae

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00:27:55,480 --> 00:27:58,200
that live inside
the jellyfish's body

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00:27:58,360 --> 00:28:01,478
and photosynthesise
energy from the sun.

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00:28:10,880 --> 00:28:13,031
In open water they are fairly safe,

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00:28:13,200 --> 00:28:17,513
but the tide is sweeping the whole
swarm gently towards the Bahamas,

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00:28:17,680 --> 00:28:20,991
where hungry mouths are waiting.

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00:28:27,120 --> 00:28:30,033
Although the sea level
doesn't change much,

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00:28:30,200 --> 00:28:34,956
the tides are still pushing
an enormous volume of ocean water

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00:28:35,120 --> 00:28:39,194
through the small gaps
between the island cays.

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00:28:48,360 --> 00:28:53,355
Underwater, the tidal currents
race past soft corals...

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00:28:58,880 --> 00:29:01,440
..and on over
the sandy banks themselves.

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00:29:07,080 --> 00:29:10,118
It is an immense area of coral sand

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00:29:10,280 --> 00:29:14,035
that is only just submerged
at high tide.

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00:29:14,200 --> 00:29:20,436
This incoming tide is bringing in
a fresh supply of oceanic plankton.

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00:29:20,600 --> 00:29:22,751
Razorfish gather at the best spots

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00:29:22,920 --> 00:29:26,960
to catch the pick
of the microscopic feast.

246
00:29:29,880 --> 00:29:33,794
Although there's plenty here
for these small fish to eat,

247
00:29:33,960 --> 00:29:35,792
gathering in one place

248
00:29:35,960 --> 00:29:39,840
makes it easy
for their predators to find them.

249
00:29:42,440 --> 00:29:45,877
A nurse shark is little threat.

250
00:29:48,240 --> 00:29:51,233
(CHIRPS AND CLICKS)
But this sound...

251
00:29:51,400 --> 00:29:54,234
heralds a quite different danger.

252
00:30:06,200 --> 00:30:08,954
A bottlenose dolphin.

253
00:30:12,520 --> 00:30:18,630
It's using its sonar
to locate razorfish beneath the sand.

254
00:30:26,600 --> 00:30:30,389
Once it finds a suitable target,
it simply digs out its prey.

255
00:31:06,400 --> 00:31:11,395
The buried fish have no defence
against this attack.

256
00:31:11,560 --> 00:31:15,395
They simply have to wait
and hope they aren't found out.

257
00:31:28,840 --> 00:31:33,357
This dolphin appears to have
a razorfish craving.

258
00:31:33,520 --> 00:31:35,512
Well, she is pregnant.

259
00:31:45,440 --> 00:31:47,716
Success at last.

260
00:32:00,240 --> 00:32:03,870
The incoming tide
sweeps on towards America,

261
00:32:04,040 --> 00:32:07,158
flooding across vast flat
plains of seagrass.

262
00:32:07,320 --> 00:32:09,710
They are so shallow
that, at low tide,

263
00:32:09,880 --> 00:32:14,113
all large fish are forced
to retreat into deep water channels,

264
00:32:14,280 --> 00:32:17,034
like these nurse shark...

265
00:32:19,920 --> 00:32:21,877
..and stingrays.

266
00:32:22,040 --> 00:32:25,431
Both predators hunt crustaceans
on the seagrass beds,

267
00:32:25,600 --> 00:32:28,115
but until the tide
brings enough water,

268
00:32:28,280 --> 00:32:30,636
they will have to wait.

269
00:32:38,400 --> 00:32:41,711
So now, for this tulip snail,
it appears safe

270
00:32:41,880 --> 00:32:45,317
to patrol the shallows
in search of a meal.

271
00:32:45,480 --> 00:32:47,597
But is it?

272
00:32:54,760 --> 00:32:56,991
This is a rather bigger snail.

273
00:32:57,160 --> 00:33:02,952
At five kilograms in weight,
the giant horse conch

274
00:33:03,120 --> 00:33:08,912
has little to fear from any shark,
and it has a taste for tulip snail.

275
00:33:14,920 --> 00:33:18,118
Sensing the approaching danger,

276
00:33:18,280 --> 00:33:20,237
the snail flees.

277
00:33:22,760 --> 00:33:24,831
But, in a world of snail paces,

278
00:33:25,000 --> 00:33:27,640
the conch
is something of a Ferrari.

279
00:33:27,800 --> 00:33:30,360
It calls for desperate measures.

280
00:33:34,760 --> 00:33:38,515
Exhausted by the effort
of its last—ditch attempt,

281
00:33:38,680 --> 00:33:41,275
the tulip snail
is slowly gunned down.

282
00:33:47,200 --> 00:33:49,920
The tide has to rise
for another hour

283
00:33:50,080 --> 00:33:53,551
before the big predators can feed.

284
00:33:53,720 --> 00:33:59,000
But out on the flats, the scent of
dying snail wafts away on the tide.

285
00:34:00,920 --> 00:34:06,279
It's a scent these hermit crabs
are particularly partial to.

286
00:34:08,720 --> 00:34:13,476
It's vital that the crabs
have the best possible protection

287
00:34:13,640 --> 00:34:17,031
from the heavy teeth
of the waiting sharks and rays.

288
00:34:17,200 --> 00:34:21,114
For that, they need the shell
with the perfect fit.

289
00:34:21,280 --> 00:34:24,432
Today, there is new real estate
on offer —

290
00:34:24,600 --> 00:34:28,640
and competition
in this housing market is fierce.

291
00:34:53,240 --> 00:34:57,029
The action becomes
even more desperate

292
00:34:57,200 --> 00:35:01,035
when the shell of the devoured
snail is ready for release.

293
00:35:09,840 --> 00:35:13,470
This crab simply can't wait
any longer.

294
00:35:17,360 --> 00:35:20,990
But it's a decidedly risky
acquisition.

295
00:35:24,560 --> 00:35:26,870
The risk paid off handsomely.

296
00:35:27,040 --> 00:35:31,114
The new shell is both lighter
and stronger than the old home.

297
00:35:31,280 --> 00:35:36,594
It's not a moment too soon,
because the tide is flooding the plains.

298
00:35:38,560 --> 00:35:42,634
At last, the predators are free
to start their foraging.

299
00:35:51,920 --> 00:35:55,436
Both stingrays and shark
have an electrical sense

300
00:35:55,600 --> 00:35:59,879
which they use to search
for buried invertebrates.

301
00:36:00,040 --> 00:36:03,477
They can sense minute movements
beneath the sand.

302
00:36:06,520 --> 00:36:11,151
Finding a promising signal,
this ray digs out its meal.

303
00:36:11,320 --> 00:36:15,473
An unprotected hermit crab
would have no chance.

304
00:36:22,560 --> 00:36:26,315
Within a few hours,
the tide ebbs out once more

305
00:36:26,480 --> 00:36:29,996
and all the predators
are forced to leave.

306
00:36:33,760 --> 00:36:38,312
They will have to wait
until the next high tide

307
00:36:38,480 --> 00:36:41,200
before making
another feeding foray.

308
00:36:44,800 --> 00:36:48,271
At certain times of the year,
called the equinox,

309
00:36:48,440 --> 00:36:53,674
spring tides are exceptionally large
and rise higher than normal.

310
00:36:55,600 --> 00:37:00,914
Predators can reach the shallowest
fringes of the seagrass flats.

311
00:37:01,080 --> 00:37:05,871
These two—metre—long tarpon
are going further inshore still.

312
00:37:06,040 --> 00:37:08,714
They are heading for the mangroves.

313
00:37:10,280 --> 00:37:15,514
These flooded forests cover
huge areas of the coastal shallows.

314
00:37:17,280 --> 00:37:22,674
Extraordinarily, the roots of
the mangrove can live in salt water,

315
00:37:22,840 --> 00:37:26,197
and they make a perfect nursery
for small fish.

316
00:37:35,000 --> 00:37:39,552
Silversides and snapper
find sanctuary in the maze of roots.

317
00:37:39,720 --> 00:37:43,350
Big predators
seldom find a way in here.

318
00:37:49,920 --> 00:37:53,470
And now the tide
is falling once more.

319
00:37:56,000 --> 00:37:59,755
The water starts losing
what little oxygen it contained,

320
00:37:59,920 --> 00:38:02,560
and quickly becomes stagnant.

321
00:38:05,400 --> 00:38:08,837
Most predators
have abandoned the mangroves,

322
00:38:09,000 --> 00:38:14,075
but the tarpon are still here,
trapped by the falling tide.

323
00:38:18,520 --> 00:38:21,718
Dissolved oxygen
is fast running out,

324
00:38:21,880 --> 00:38:25,920
but they have a vital survival
technique...

325
00:38:27,080 --> 00:38:29,800
..they can breathe air.

326
00:38:40,680 --> 00:38:42,592
Pumped up with fresh oxygen,

327
00:38:42,760 --> 00:38:46,390
they can easily out—manoeuvre
the dozy silversides.

328
00:39:10,480 --> 00:39:12,676
The tide has turned again.

329
00:39:15,480 --> 00:39:17,597
And this is no ordinary tide.

330
00:39:17,760 --> 00:39:21,071
Since it is the equinox,
the tide is rising fast,

331
00:39:21,240 --> 00:39:23,038
but now, out to sea,

332
00:39:23,200 --> 00:39:27,513
a hurricane is on its way,
forcing the tide yet higher.

333
00:39:57,080 --> 00:40:03,031
The passing storm leaves large
areas of the coast flooded.

334
00:40:05,760 --> 00:40:09,071
Low—lying islands,
like the Bahamas,

335
00:40:09,240 --> 00:40:13,757
are particularly prone
to the storm flooding.

336
00:40:13,920 --> 00:40:17,436
The sun's power here is immense.

337
00:40:18,560 --> 00:40:22,440
As the tide recedes and the
remaining flood water evaporates,

338
00:40:22,600 --> 00:40:26,071
a remarkable transformation
takes place.

339
00:40:36,240 --> 00:40:41,156
The mud is coated
with a magical world of salt.

340
00:40:49,720 --> 00:40:53,760
Any remaining water
is extremely salty.

341
00:40:53,920 --> 00:40:56,799
Very few creatures
can survive here...

342
00:40:56,960 --> 00:40:59,759
except brine shrimp.

343
00:41:05,880 --> 00:41:08,156
And, on the water's edge —

344
00:41:08,320 --> 00:41:10,391
brine flies.

345
00:41:10,560 --> 00:41:17,034
Both are the favourite food
of an extraordinary animal.

346
00:41:18,280 --> 00:41:21,114
The Caribbean flamingo.

347
00:41:24,160 --> 00:41:28,518
Remarkably, they actually seek out
such briny places.

348
00:41:28,680 --> 00:41:32,720
They are the best spots
for them to find their food.

349
00:41:46,120 --> 00:41:48,840
They also provide the protection

350
00:41:49,000 --> 00:41:52,357
the flamingos need
to raise their young.

351
00:41:52,520 --> 00:41:56,514
Nesting sites like this
are surrounded by corrosive brine.

352
00:41:56,680 --> 00:41:59,115
It's a formidable barrier

353
00:41:59,280 --> 00:42:04,116
to any predator
seeking to dine on flamingo chicks.

354
00:42:08,480 --> 00:42:12,872
The flamingos take the precaution
of building raised nests

355
00:42:13,040 --> 00:42:15,680
just in case of further flooding.

356
00:42:22,560 --> 00:42:26,873
Strangely, it's actually
the power of the storm tides

357
00:42:27,040 --> 00:42:32,638
that gives the flamingos food and
a perfect habitat in which to breed.

358
00:42:45,080 --> 00:42:48,278
The breeding of many animals
in the ocean

359
00:42:48,440 --> 00:42:51,831
is closely co—ordinated
with the tidal cycles.

360
00:42:52,000 --> 00:42:57,314
The half moon in November.
It's the time of small tides.

361
00:43:01,960 --> 00:43:04,236
Christmas Island in the Pacific.

362
00:43:06,040 --> 00:43:09,317
Strange happenings are afoot.

363
00:43:15,560 --> 00:43:18,598
It's one of only
a few nights each year

364
00:43:18,760 --> 00:43:21,753
when female Christmas Island crabs

365
00:43:21,920 --> 00:43:25,470
risk heading down towards the sea.

366
00:43:27,480 --> 00:43:30,359
They number in tens of thousands

367
00:43:30,520 --> 00:43:35,720
and all of them are laden
with hundreds of eggs.

368
00:43:37,960 --> 00:43:40,270
They have to shed them
into the ocean

369
00:43:40,440 --> 00:43:43,194
if the eggs are to develop
into baby crabs.

370
00:43:47,560 --> 00:43:49,472
But these are land crabs

371
00:43:49,640 --> 00:43:53,839
and they can neither swim
nor breathe underwater.

372
00:44:03,760 --> 00:44:05,956
There's a great risk of drowning.

373
00:44:06,120 --> 00:44:11,434
That is why they pick the smallest
tides, to minimise the danger.

374
00:44:37,800 --> 00:44:40,520
The eggs will develop far offshore.

375
00:44:40,680 --> 00:44:43,434
And, in exactly one month's time,

376
00:44:43,600 --> 00:44:48,834
a swarm of baby crabs will return,
again choosing the perfect tide.

377
00:44:55,400 --> 00:44:58,757
Whether it's the daily
or monthly cycle,

378
00:44:58,920 --> 00:45:02,880
tides are the rhythm of the ocean —

379
00:45:03,040 --> 00:45:04,633
its pulsing clock.

380
00:45:04,800 --> 00:45:07,520
For every tide brings opportunity

381
00:45:07,680 --> 00:45:10,752
to marine life
somewhere in the world.

382
00:45:14,280 --> 00:45:18,718
Now, a spring tide
is flooding the shallows,

383
00:45:18,880 --> 00:45:21,111
and hunters are on the prowl.

384
00:45:21,280 --> 00:45:24,273
A small group of bottlenose dolphin

385
00:45:24,440 --> 00:45:26,636
are working their way inshore

386
00:45:26,800 --> 00:45:31,192
to start a quite extraordinary
hunting campaign.

387
00:45:56,360 --> 00:46:02,231
After one successful pass,
the dolphin move off to start again.

388
00:46:02,400 --> 00:46:06,394
One animal peels off from the group
and swims in a circle,

389
00:46:06,560 --> 00:46:12,670
stirring up the mud and driving
the mullet towards the other dolphins.

390
00:46:14,160 --> 00:46:19,474
It's a remarkable team effort
and it's extremely effective.

391
00:46:25,480 --> 00:46:28,120
The dolphin will feed like this

392
00:46:28,280 --> 00:46:33,833
for as long as the tide grants them
access to the shallows.

393
00:47:18,960 --> 00:47:20,758
Eventually,

394
00:47:20,920 --> 00:47:25,551
the falling tide will force
the dolphin to leave the flats

395
00:47:25,720 --> 00:47:31,159
and the mullet will be safe
once more, until the next high tide.

396
00:47:32,320 --> 00:47:38,112
Because, in the ocean,
every turn of the tide

397
00:47:38,280 --> 00:47:43,116
spells the difference
between life and death somewhere.