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The coast — the frontier
between land and sea.

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00:00:47,760 --> 00:00:51,754
This is the most dynamic
of all the ocean habitats.

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00:00:51,920 --> 00:00:54,640
The challenge here
is to survive change,

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00:00:54,800 --> 00:00:56,712
extreme change.

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00:01:23,680 --> 00:01:27,640
Cape Douglas, on the most
westerly Galapagos Island,

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totally unprotected from
the massive rollers of the Pacific,

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00:01:32,600 --> 00:01:36,389
and one of the roughest coastlines
in the world.

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The marine iguanas of the Galapagos

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are the world's only
sea—going lizards.

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Seaweed is all they eat, but doing so
is a dangerous business.

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The local crabs have become
specially flattened,

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minimising the effect
of the pounding waves.

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And the iguanas have huge claws
to grip the rocks.

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This seaweed really is fast food.

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There are only a few seconds
in which to grab a few mouthfuls

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before the next breaker
comes pounding in.

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Females feed
only on the exposed rocks,

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but the larger males dive beneath
the surface to reach the weed.

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They go as deep as ten metres,

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for there,
below the destructive waves,

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they find the best fronds.

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Cold—blooded, they have to return
to land after about ten minutes

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to warm up again in the sun.

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Finding food is not the only
challenge for coastal residents.

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These rocky shores are hardly
a safe place to lay their eggs.

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Each year, the marine iguanas

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have to journey inland
to find a more suitable one.

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The females lay their eggs
in burrows

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and leave them there to hatch.

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To do that,
they need nice soft sand.

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Down at the water's edge,
it was easy to escape danger

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in rocky crevices.

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Up here, the females
are dangerously exposed.

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A Galapagos hawk.

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The lizards don't give up
without a struggle.

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These hawks stay on the coast
all year, but they are exceptional.

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Most of the birds
that frequent this frontier

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spend most of their time
in or above the open ocean.

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However, all seabirds have to come
to land in order to lay their eggs.

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And, after many lonely months
spent searching the ocean for food,

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they have to re—establish
social relationships.

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Frigate birds display

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and exchange nest material.

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Waved albatross dance.

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The need to lay eggs on firm ground
ties the albatross to the coast,

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but parental responsibilities
are shared.

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While one looks after the egg,
the other can go off to feed.

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00:06:54,080 --> 00:06:57,437
The need to breed
brings many different animals

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to the coast each year
for a few weeks.

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00:07:00,360 --> 00:07:03,478
Male sea turtles
spend all their lives at sea,

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00:07:03,640 --> 00:07:09,477
but the females, like birds,
must come to land to lay their eggs.

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00:07:14,920 --> 00:07:19,995
To do that, green turtles that live
and feed off the coast of Brazil

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swim 1,500 miles to the tiny island
of Ascension,

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that lies bang in the middle
of the Atlantic Ocean.

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How they manage to navigate
with such accuracy

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and find this tiny lump of rock
just seven miles wide is a mystery.

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But, each year, up to 5,000 turtles
manage to do so,

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and then, close to
the coast of Ascension, they mate.

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Travelling to and from Ascension
and nesting can take six months.

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Throughout the entire time,
none of them feed at all.

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After mating,

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a female has to leave her natural
element and haul herself onto land.

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She does so at night, laying three
or four times at 15—day intervals.

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After that, she swims back
to the seas off Brazil.

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She returns to this very same
island throughout her life.

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Remarkably, all the world's sea
turtles return, year after year,

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to a few traditional
breeding sites.

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Crab Island in Australia
is one of them.

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This tiny two—mile long
crescent of sand,

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lying a few miles off
Queensland's northerly tip,

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provides nesting sites

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for half the population
of one of the rarest sea turtles.

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Flat—backed turtles
are over a metre long,

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but they have to be careful—

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there are other giant reptiles
here, too.

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Salt—water crocodiles.

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Every night throughout the year,
there are flat—backs

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burying their eggs
all along this stretch of sand.

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Nine weeks later,

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and things are about to happen.

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These eyes shining in the darkness
belong to night herons.

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As if from nowhere, hundreds
of birds appear on the sand dunes.

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Pelicans wait patiently.

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Jabiru storks pace up and down.

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Before long, they see
what they've been waiting for.

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Because these turtles
lay their eggs throughout the year,

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the hatchlings emerge nightly in
a steady trickle of beak—sized meals.

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The pelicans' broad beaks allow them
to dig out the hatchlings

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before the herons
can spear them on the surface.

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The surf may be
hundreds of metres away

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and at least a third
do not survive the journey.

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It's not just the birds
that take them.

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Crocodiles, sharks and hungry fish
are all waiting in the shallows.

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In fact, only one in 100 hatchlings
will survive to adulthood.

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Another beach, another continent
and a very special night.

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In Costa Rica, a turtle has found
a way of reducing these dangers.

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When Ridley's turtles arrive
to lay their eggs,

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they don't come in tens
or hundreds, but in thousands.

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In the next six days, around 400,000
females willvisit this beach.

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At the peak time, 5,000 are
coming and going each hour.

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The beach gets so crowded,
they have to clamber over one another

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to find bare sand
where they can dig a nest hole.

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40 million eggs
are laid in these few days.

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These turtles ensure
that six weeks later,

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when their hatchlings emerge,
it's not just a trickle.

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It's a flood!

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On some nights,
over two million hatchlings

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race down to the sea together.

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With so many
appearing simultaneously,

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the predators are overwhelmed.

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Most of the turtles
reach the sea safely.

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Leaving the sea and emerging
onto land is hard enough for turtles.

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It's even harder for fish.

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Each year, for hundreds of miles
along the Newfoundland coast,

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capelin throw themselves
onto the beaches.

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At least a million tonnes of fish
floundering out of the water —

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a real gift for scavenging
eagles and gulls.

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Odd though it may seem
for the fish,

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the capelin, like the turtles, have
also come out of the sea to breed.

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The males are trying
to fertilise the eggs

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that the females deposit in the sand.

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Like the Ridley's turtles, they've
synchronised their mass laying with the tide.

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In a few days, it will be over.

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Most of the capelin die,

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but only after they've left
their eggs in the sand.

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Other capelin populations
lay their eggs in the ocean,

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so why do the Newfoundland fish
spawn on land?

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It seems that eggs deposited
on the beach are safer from predators

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and develop faster
than in colder waters out to sea.

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But, wherever they do so,
the huge spawning shoals

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provide the concentration of food
that seabirds need

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when THEY assemble to breed.

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95% of the world's seabirds
nest together,

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mostly in large
spectacular colonies.

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This is Funk Island, 40 miles
off the coast of Newfoundland —

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an isolated rock
crammed with breeding seabirds.

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This was the last breeding ground
for the flightless great auk,

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sadly now extinct.

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Today, it's still the world's
largest guillemot colony.

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Over a million of them share
this island with 250,000 gannets.

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It's not the lack of suitable sites

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that causes seabirds
to breed in such densities.

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Here, in the North Atlantic,

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there's a wide choice of empty
coastline the birds could use.

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The key factor limiting
seabird colonies

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seems to be availability of food
in the surrounding ocean.

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There are lots
of hungry mouths to feed

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and a constant demand for fish.

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Throughout the long summer days,
at colonies like Funk,

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there's a continual stream of birds
heading out to find food

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and returning with full crops
to feed their young.

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Gannets will travel up to 200 miles
from the colony

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on a single foraging trip.

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They are not fussy eaters

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and will take everything
from tiny sand eels to herring.

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Puffins, on the other hand,
are particular about what they eat.

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Because they can only fly
short distances,

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they only nest where there is
a good supply of food close by.

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One such place is the Sea
of Okhotsk in far eastern Russia.

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This is the island of Talan.

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Throughout the long Arctic winter
it is encircled by ice.

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But as spring approaches,
that begins to break up,

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and seabirds that have wintered
far to the south

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begin to return.

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Its isolated position
and steep cliffs

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make Talan a perfect nesting site.

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The tufted puffins arrive first.

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These are the Pacific cousins

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of our less spectacular
Atlantic species.

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Horned puffins soon follow.

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00:19:24,400 --> 00:19:28,997
In all, 14 different species
return to Talan each spring.

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In a few weeks, the silent cliffs

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come alive to the calls
of four million breeding seabirds.

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This is a multi—storey avian city.

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Assembling in these colonies,

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after having spent
a largely solitary life at sea,

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provides the birds
with the social stimulation

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that is the key
to co—ordinating their breeding.

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By nesting and laying together,

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they ensure that most chicks will
leave the nest at the same time.

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Like the turtles, this is the way
they spread the impact of predators.

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The world's largest eagle —
Steller sea eagle —

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a third as big again
as a golden eagle.

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00:20:30,600 --> 00:20:35,755
Throughout the summer, the eagles
hunt in Talan's crowded colonies.

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00:20:46,600 --> 00:20:49,877
Riding on the updrafts,
they patrol the cliff tops,

186
00:20:50,040 --> 00:20:53,431
looking out for any kittiwake

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that ventures too far
from the rock face.

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The huge eagle swoops with
the aerial agility of a falcon.

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00:21:13,800 --> 00:21:19,353
Co—ordinated panic among the
kittiwakes confuses their attacker.

190
00:21:32,120 --> 00:21:35,158
But the eagle doesn't give up.

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00:21:47,680 --> 00:21:50,195
And it has got one.

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00:22:03,240 --> 00:22:05,709
Another kind of seabird on Talan

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00:22:05,880 --> 00:22:11,000
has a particularly effective way
of defending itself against predators,

194
00:22:11,160 --> 00:22:15,200
but it doesn't appear
until an hour before sunset.

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As if from nowhere, dense swarms
of seabirds suddenly arrive offshore.

196
00:22:28,000 --> 00:22:30,799
They've spent the day
feeding far away

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00:22:30,960 --> 00:22:33,873
where the sea ice
has already broken up.

198
00:22:34,040 --> 00:22:38,478
They are crested auklets,
hardly bigger than starlings.

199
00:22:38,640 --> 00:22:41,439
A million of them
return to Talan each year

200
00:22:41,600 --> 00:22:43,910
to nest in its fields of boulders.

201
00:22:49,840 --> 00:22:51,638
For the hour before sunset,

202
00:22:51,800 --> 00:22:56,795
the hillsides come alive
with huge flocks of circling auklets.

203
00:22:56,960 --> 00:23:01,352
They're nervous.
No one wants to be the first to land.

204
00:23:05,880 --> 00:23:10,113
Auklets are very social
when they're together at the coast.

205
00:23:10,280 --> 00:23:13,159
One advantage of nesting
in such densities

206
00:23:13,320 --> 00:23:17,109
may be the chance to share
information on feeding sites.

207
00:23:17,280 --> 00:23:21,513
It also gives them
the opportunity to court.

208
00:23:26,920 --> 00:23:30,960
But, most importantly,
there is safety in numbers.

209
00:23:35,280 --> 00:23:36,999
Ravens and peregrines

210
00:23:37,160 --> 00:23:40,676
circle above the scree slope
every evening.

211
00:23:55,040 --> 00:24:00,354
By taking off together, the auklets
hope to confuse the predators.

212
00:24:30,400 --> 00:24:34,076
Eventually,
their persistence pays off.

213
00:24:44,200 --> 00:24:47,159
The birds that face
the greatest challenge

214
00:24:47,320 --> 00:24:51,109
in coming to the coast to nest
are surely the penguins.

215
00:25:02,440 --> 00:25:06,593
Unable to fly,
they have no alternative

216
00:25:06,760 --> 00:25:08,877
but to brave the immense waves.

217
00:25:18,400 --> 00:25:21,359
Most penguins live
in the southern ocean,

218
00:25:21,520 --> 00:25:25,400
and they have to accept
being hurled about by the surf.

219
00:25:43,320 --> 00:25:44,913
Whatever the weather,

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00:25:45,080 --> 00:25:48,835
the penguin parents have
to come back to feed their chicks.

221
00:25:58,320 --> 00:26:00,789
A southern sea—lion bull.

222
00:26:00,960 --> 00:26:06,115
He knows the penguins always use
the same traditional landing beach.

223
00:26:09,640 --> 00:26:11,950
Having braved the thundering surf,

224
00:26:12,120 --> 00:26:16,319
the penguins have to make a mad dash
across open rock to their nests.

225
00:26:37,800 --> 00:26:42,113
Despite his massive size
and a body adapted for swimming,

226
00:26:42,280 --> 00:26:47,480
the bull chases the penguins
for 40 or 50 metres across the rocks.

227
00:27:39,280 --> 00:27:44,480
Having caught his penguin, the
sea—lion carries it into deeper water,

228
00:27:44,640 --> 00:27:49,556
where, by violently thrashing
the little body, he skins his meal.

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00:27:57,200 --> 00:28:02,070
The seas around the Falklands are
some of the roughest in the world.

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00:28:03,760 --> 00:28:06,673
In spite of that,
the southern ocean is home

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00:28:06,840 --> 00:28:11,596
to millions of tiny seabirds hardly
bigger than swallows — petrels.

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00:28:11,760 --> 00:28:15,549
Being so small, they're very
vulnerable to the bad weather.

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00:28:15,720 --> 00:28:18,394
A storm can blow them
miles off course

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00:28:18,560 --> 00:28:22,031
and keep them
away from their nests for days.

235
00:28:22,200 --> 00:28:28,037
But these birds have developed
an effective solution to the problem.

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00:28:28,200 --> 00:28:31,477
They lay a rather special egg.

237
00:28:31,640 --> 00:28:35,554
Most birds' eggs, left exposed
for even a few hours,

238
00:28:35,720 --> 00:28:37,871
will chill and never hatch.

239
00:28:38,040 --> 00:28:40,157
But these eggs are different.

240
00:28:40,320 --> 00:28:44,712
They can be left undamaged
for several days without incubation

241
00:28:44,880 --> 00:28:48,590
while the parents struggle home
through the storm.

242
00:28:49,960 --> 00:28:55,592
Prions have also come up with
a good way to avoid most predators.

243
00:28:55,760 --> 00:28:59,197
They never come back to the coast
until after dark.

244
00:29:02,000 --> 00:29:04,595
These are thin—billed prions.

245
00:29:04,760 --> 00:29:07,958
Their burrows honeycomb
this Falklands hillside.

246
00:29:08,120 --> 00:29:09,918
It's deserted in daylight,

247
00:29:10,080 --> 00:29:11,673
but as soon as it's dark

248
00:29:11,840 --> 00:29:15,311
and difficult
for airborne predators to hunt,

249
00:29:15,480 --> 00:29:17,472
the prions return.

250
00:29:25,120 --> 00:29:27,555
As soon as they land, they call.

251
00:29:27,720 --> 00:29:29,313
(CHIRPING)

252
00:29:32,280 --> 00:29:37,196
The problem, of course, is finding
your burrow among all the others.

253
00:29:37,360 --> 00:29:41,274
He's listening out
for his mate's call.

254
00:29:43,280 --> 00:29:45,078
And down he goes.

255
00:29:52,360 --> 00:29:54,511
The Alaskan coast.

256
00:29:54,680 --> 00:29:59,630
It's spring, and the last
of the winter storms is subsiding.

257
00:29:59,800 --> 00:30:03,794
The plankton in this sea
is in bloom again.

258
00:30:04,800 --> 00:30:08,476
Just off shore, humpback whales
have returned to feed.

259
00:30:14,320 --> 00:30:15,913
For these huge animals,

260
00:30:16,080 --> 00:30:19,790
there's a real risk
in coming into such shallow water,

261
00:30:19,960 --> 00:30:23,510
and each year, a good number
of them pay the price.

262
00:30:27,240 --> 00:30:30,472
It's an ignominious ending
for an ageing whale,

263
00:30:30,640 --> 00:30:34,634
but so much flesh
will not go to waste.

264
00:30:36,400 --> 00:30:39,711
A black bear
emerges cautiously from the woods.

265
00:30:48,680 --> 00:30:52,833
Visitors to the coast
that don't come to breed,

266
00:30:53,000 --> 00:30:55,834
usually come to scavenge.

267
00:30:56,000 --> 00:31:00,836
A whole range of animals exploit
the enormous quantity of food

268
00:31:01,000 --> 00:31:04,994
that washes up every day
on coastlines around the world.

269
00:31:05,160 --> 00:31:08,039
But, like so much of the coast,

270
00:31:08,200 --> 00:31:12,911
the quantity of flotsam and jetsam
is unpredictable.

271
00:31:13,080 --> 00:31:15,436
Nobody can rely on it alone.

272
00:31:18,040 --> 00:31:21,716
This carcass even attracted
a shy pack of wolves,

273
00:31:21,880 --> 00:31:26,716
only too happy to anoint themselves
with the scent of rotting whale.

274
00:31:31,600 --> 00:31:37,198
It was months before the scavengers
finally cleaned up all the meat

275
00:31:37,360 --> 00:31:41,149
on this huge and unpredictable
gift from the sea.

276
00:31:44,600 --> 00:31:47,638
Whales give birth
to their young at sea,

277
00:31:47,800 --> 00:31:50,713
so can spend
their entire lives there.

278
00:31:50,880 --> 00:31:52,519
Other marine mammals —

279
00:31:52,680 --> 00:31:56,276
ones that are, in fact,
distant cousins of bears —

280
00:31:56,440 --> 00:32:00,992
have to return each year
to their ancestral home on land.

281
00:32:04,000 --> 00:32:05,798
The high Arctic.

282
00:32:05,960 --> 00:32:09,192
Here lives one of them —
the walrus.

283
00:32:18,200 --> 00:32:21,671
Walruses spend
nearly all their lives at sea.

284
00:32:21,840 --> 00:32:24,196
But each year, for a few weeks,

285
00:32:24,360 --> 00:32:26,511
they have to return to the coast.

286
00:32:28,560 --> 00:32:33,077
They seek out isolated beaches like
Round Island in the northern Pacific.

287
00:32:33,240 --> 00:32:39,032
Suitable sites like this,
free from bears, are so scarce

288
00:32:39,200 --> 00:32:42,318
that at times
as many as 14,000 animals

289
00:32:42,480 --> 00:32:45,951
will cram themselves
onto this one beach.

290
00:32:54,240 --> 00:32:58,280
When they first emerge from the sea,
the walrus are white.

291
00:32:58,440 --> 00:33:01,956
As warm—blooded animals
living in a very cold ocean,

292
00:33:02,120 --> 00:33:03,713
they conserve heat

293
00:33:03,880 --> 00:33:08,318
by keeping their blood concentrated
in the core of their bodies.

294
00:33:08,480 --> 00:33:10,631
On land, it's warm enough

295
00:33:10,800 --> 00:33:14,271
for them to allow
their outer blood vessels to dilate.

296
00:33:14,440 --> 00:33:17,956
That turns their skin
from white to pink.

297
00:33:24,600 --> 00:33:28,116
Now they can moult
the outer layers of their skin,

298
00:33:28,280 --> 00:33:31,557
rubbing themselves
up against the rocks.

299
00:33:33,480 --> 00:33:39,158
But more than anything else,
coming to land brings the walrus relief

300
00:33:39,320 --> 00:33:41,357
from having to spend energy

301
00:33:41,520 --> 00:33:45,400
maintaining body temperature
in an icy—cold ocean.

302
00:33:47,560 --> 00:33:52,191
Heat conservation, in fact,
may be the primary reason

303
00:33:52,360 --> 00:33:57,230
so many sea mammals are forced
to return to the land each year.

304
00:34:01,080 --> 00:34:03,072
The world's coldest seas

305
00:34:03,240 --> 00:34:05,391
are in Antarctica.

306
00:34:05,560 --> 00:34:09,349
Each spring, half the world's
southern elephant seals

307
00:34:09,520 --> 00:34:12,240
return to the island
of South Georgia.

308
00:34:12,400 --> 00:34:17,350
Elephant seals have a particularly
thick insulation of blubber

309
00:34:17,520 --> 00:34:19,239
that keeps them warm.

310
00:34:19,400 --> 00:34:23,155
For them, breeding is the only
reason to leave the sea.

311
00:34:27,880 --> 00:34:30,395
With temperatures down to minus 20,

312
00:34:30,560 --> 00:34:32,552
and 100—mile—an—hour winds,

313
00:34:32,720 --> 00:34:35,189
It can't be comfortable
on the beach.

314
00:34:35,360 --> 00:34:39,149
But heat dissipates more rapidly
through water than air.

315
00:34:39,320 --> 00:34:41,391
So even in these conditions,

316
00:34:41,520 --> 00:34:44,513
their young, which at first
don't have a thick coat of blubber,

317
00:34:44,680 --> 00:34:46,876
will be far warmer on the land.

318
00:34:47,040 --> 00:34:52,399
Once the males are established on
the beach, the females soon follow.

319
00:34:56,520 --> 00:34:58,512
Within just ten days,

320
00:34:58,680 --> 00:35:03,755
the empty beach fills up
with 6,000 elephant seals.

321
00:35:05,000 --> 00:35:07,959
Almost immediately,
the females give birth

322
00:35:08,120 --> 00:35:10,351
to pups sired the previous year.

323
00:35:19,640 --> 00:35:24,999
Their milk is very rich and the
pups grow astonishingly quickly.

324
00:35:32,720 --> 00:35:36,634
In just three weeks,
they turn from thin bags of skin,

325
00:35:36,800 --> 00:35:39,110
to fat balls of blubber.

326
00:35:40,600 --> 00:35:45,152
As soon as they've given birth, the
females become sexually receptive.

327
00:35:45,320 --> 00:35:50,793
Now the advantages of breeding
in dense colonies become clear.

328
00:35:50,960 --> 00:35:53,919
Females can choose from many males,

329
00:35:54,080 --> 00:35:58,996
while successful males can have
access to lots of females.

330
00:36:03,440 --> 00:36:08,276
But to gain that access
and control a harem of females,

331
00:36:08,440 --> 00:36:11,114
the bull must be prepared to fight.

332
00:36:16,560 --> 00:36:18,552
(ROARS)

333
00:36:30,320 --> 00:36:36,271
The larger the male, the louder
the roar, the more likely he is to win.

334
00:36:46,040 --> 00:36:48,509
When males are well matched,

335
00:36:48,680 --> 00:36:53,118
these bloody battles
will last 20 minutes or more.

336
00:37:09,960 --> 00:37:12,680
Eventually, the loser retreats

337
00:37:12,840 --> 00:37:16,754
into a stream already pink
with his own blood.

338
00:37:27,400 --> 00:37:32,555
These battles certainly help
females select the strongest bulls,

339
00:37:32,720 --> 00:37:35,360
but they bring great dangers
to the pups.

340
00:37:44,800 --> 00:37:48,077
Each year, in the denser parts
of the colony,

341
00:37:48,240 --> 00:37:51,392
a fifth of the pups
are crushed to death.

342
00:37:51,560 --> 00:37:53,870
This is why
it may be better to mate

343
00:37:54,040 --> 00:37:56,874
at the edge of the beach
close to the sea.

344
00:38:02,120 --> 00:38:05,557
Less dominant males
hide in the surf.

345
00:38:05,720 --> 00:38:09,270
They are waiting to try and steal
an illicit mating

346
00:38:09,440 --> 00:38:11,796
with females as they come and go.

347
00:38:13,840 --> 00:38:18,517
This male knows he has been spotted
by the big bull

348
00:38:18,680 --> 00:38:22,390
who claims all the females
on this part of the beach.

349
00:39:24,000 --> 00:39:27,516
Breeding in groups
can bring advantages to pups

350
00:39:27,680 --> 00:39:29,478
as well as to adults.

351
00:39:35,720 --> 00:39:37,837
Along the coast of Patagonia,

352
00:39:38,000 --> 00:39:43,075
southern sea—lions breed together
in groups several hundred strong.

353
00:39:43,240 --> 00:39:48,918
For the growing pup, these colonies
act rather like a school.

354
00:39:49,080 --> 00:39:54,758
The bonds developed here may be
vital for the rest of their lives.

355
00:39:54,920 --> 00:39:56,832
Sea—lions are social animals.

356
00:39:57,000 --> 00:39:59,469
As adults and young
forage together,

357
00:39:59,640 --> 00:40:05,034
they probably share information
about good feeding sites.

358
00:40:06,080 --> 00:40:10,313
Conditions could hardly be better
for the growing youngsters.

359
00:40:10,480 --> 00:40:15,919
As the tide goes out, it leaves
a selection of sheltered pools.

360
00:40:16,080 --> 00:40:19,676
Perfect places
for learning to swim.

361
00:40:53,920 --> 00:40:56,754
At high tide,
it's easy for the pups

362
00:40:56,920 --> 00:41:01,039
to take their first
experimental dips in the surf.

363
00:41:34,160 --> 00:41:36,152
A killer whale.

364
00:41:38,480 --> 00:41:43,350
These young pups have never seen
anything like it before.

365
00:41:54,280 --> 00:41:57,398
The whales,
though, are very experienced.

366
00:41:57,560 --> 00:42:01,600
Each year, this same group
turns up along the coast

367
00:42:01,760 --> 00:42:06,039
at precisely the same time
as the pups start to swim.

368
00:42:14,360 --> 00:42:16,875
The whales
need to surprise the pups,

369
00:42:17,040 --> 00:42:21,080
so they have stopped calling
to each other, and keep silent.

370
00:42:29,480 --> 00:42:31,278
Speed is everything.

371
00:42:34,280 --> 00:42:39,116
The whales do not take pups
that are out of the water,

372
00:42:39,280 --> 00:42:42,398
but their momentum
can drive them up the beach

373
00:42:42,560 --> 00:42:45,837
and then there's real danger
of getting stuck.

374
00:44:17,680 --> 00:44:22,357
The whale has to thrash in this
frenzied way to get off the beach.

375
00:44:22,520 --> 00:44:27,037
Most of the pups are taken
into deep water while still alive.

376
00:44:27,200 --> 00:44:32,070
And there the whales,
apparently, play with them.

377
00:44:54,000 --> 00:44:59,234
Often, an adult whale
is joined in the game by a youngster.

378
00:44:59,400 --> 00:45:02,438
It may be learning
how to grab a seal pup

379
00:45:02,600 --> 00:45:05,479
before it risks
a drive up the beach.

380
00:45:12,680 --> 00:45:16,674
Whatever the reason,
the seal pup — still alive —

381
00:45:16,840 --> 00:45:21,278
is tossed back and forth
for over half an hour.

382
00:45:52,400 --> 00:45:54,198
Even when the pup is dead,

383
00:45:54,360 --> 00:45:57,398
the whales' sport
is not completely over.

384
00:46:27,080 --> 00:46:28,673
We can only speculate

385
00:46:28,840 --> 00:46:33,312
at the real reasons behind
this extraordinary behaviour.

386
00:46:45,960 --> 00:46:50,079
But, for the whales,
the hunting season is a short one.

387
00:46:50,240 --> 00:46:54,712
Before long, the pups learn
to stay clear of the water,

388
00:46:54,880 --> 00:46:57,600
and the whales
become less successful.

389
00:46:57,760 --> 00:47:00,480
After two weeks, they move on.

390
00:47:00,640 --> 00:47:03,951
The killing season is over.

391
00:47:13,040 --> 00:47:16,033
That's how it often happens
along the coast.

392
00:47:16,200 --> 00:47:18,237
Things are always changing.

393
00:47:18,400 --> 00:47:20,676
They're never the same for long

394
00:47:20,840 --> 00:47:25,676
in this, the most dynamic
of all the ocean's habitats.