The Hunt (2015) s01e06 Episode Script

The coast Nature's most demanding hunting ground.
So hazardous that few predators stay here all year.
This frontier between sea and land is continuously changing.
Opportunities never last long.
To hunt at the coast, you have to be in the right place at just the right time.
On the east coast of America, in the tidal creeks of South Carolina, a team of hunters is about to leave the safety of their natural habitat.
This group of bottlenose dolphins has perfected a unique hunting strategy.
It relies on teamwork, intelligence and timing.
But beaching themselves like this is also difficult and dangerous.
Hunting is only possible for three hours around low tide, when the mud banks are exposed.
Razor-sharp oysters cover much of the shore.
Beaching here could be lethal.
The hunters need to find a stretch of shoreline with just the right slope.
Too level, and the dolphins risk stranding.
Too steep and they can't force their prey from the water.
Working as a team, the dolphins surround the fish, driving them towards the shore.
Attacking in perfect synchrony, the dolphins create a bow wave.
It carries their prey onto the muddy banks.
Other fish-eaters profit from their daring.
Herons and gulls follow every hunt.
To get to the fish first, the dolphins drive themselves high up the bank.
But if they go too far, they risk stranding.
To prevent fish escaping between them, the dolphins all beach themselves on the same side.
Always the right.
But this has a cost.
Each time they grab a fish, they also take in a mouthful of mud.
The grit gradually wears down their teeth but on one side only.
In time, these teeth get so worn down that older dolphins can no longer hunt like this and must find other ways to catch fish.
Within a few hours, the banks will vanish once again beneath the muddy water.
The ebb and flow of the tide dominates the lives of all who try to hunt on the coast.
Northern Australia has the highest tides in the tropics, which expose vast areas of shoreline.
And here lives a truly extraordinary species of octopus.
Octopuses are marine animals, they live and breathe underwater.
At low tide, most octopuses would be imprisoned in their rocky pools.
But this is no ordinary octopus.
It's the only one specially adapted to walk on land.
It pulls itself along, using the hundreds of tiny suckers that line its arms.
Hunting for crabs, it walks from pool to pool.
Apart from a rather startled fish this one is empty.
So the octopus moves on.
A rock pool may seem like a safe refuge.
But the octopus' suckers enable it to move just as stealthily in water as out of it.
Nowhere is safe when this octopus is around.
Everything living here must march to the rhythm of the coast.
Regiments of soldier crabs, several thousand strong, march and counter-march across these Australian beaches.
They sift out microscopic food.
But they can only feed for a few hours while the sand remains damp.
And it's not just the tide they're racing against.
Hunting birds follow in their wake.
But the army is undeterred.
They swarm in such huge numbers that their predators make little impact upon them.
But safety in numbers isn't the only defense on these flats.
Another crab here has a different strategy.
The sand bubbler crab, no bigger than a pea.
They also sift out tiny food particles and then leave the sand as pellets in their wake.
Sand bubblers are wary and never venture far from their burrows.
The crabs position their sand balls very carefully to ensure there is a clear path back to safety.
As soon as the coast is clear, they're off again, racing to feed before the sand dries out.
The industry of thousands transforms the whole beach until the tide returns once more.
Few hunters make the coast their permanent home.
Most only visit to take advantage of short-lived opportunities.
On the coast of Thailand, a most unlikely visitor waits for the tide to ebb.
Long-tailed macaques feed mostly on fruit and leaves in the forest.
But these have learned to supplement their vegetarian diet with seafood.
As the tide begins to fall, the macaques make their way down to the shore.
A beach-side restaurant is about to open.
There's plenty of food here, if you know how to get at it.
The macaques have learnt to use heavy rocks as tools to break open the sea snails.
It takes a great deal of skill to master this technique, but not everyone has got the hang of it.
You have to be ingenious to make a living at the coast.
As the tide falls still further, it reveals the next course.
To feed on this dish, they need a stone tool with a very particular shape.
They're after rock oysters.
To crack the shells open, they must strike the oyster in just the right place with their chosen tool.
The lowest tide reveals a course that is particularly delicious but also very hard to collect.
Crabs have good eyesight and can move fast.
So catching them requires a special trick.
Before pouncing, the macaques wait for a wave to obscure their attack.
Macaques learn their skills by watching their parents.
But some techniques do take time to perfect.
And time and tide waits for no macaque.
The returning water closes the beach restaurant for another day.
It's not just tides that rule the lives of those that live on the coast.
The shores of Chile are battered by some of the wildest and coldest seas.
This coastline is home to a remarkable little hunter The South American marine otter.
The world's smallest sea mammal.
This rare and elusive otter is half the size of its European cousin.
They live along the Pacific coast of South America, right down to Cape Horn at the very tip of the continent.
Surprisingly, the pounding breakers aren't a problem for the little otters.
But the cold water is.
A continuous frigid current sweeps up from Antarctica.
A small body loses heat faster than a large one, and so these tiny otters can only hunt in the chilly water for 20 minutes at a time.
But their small size enables them to reach the fish and crabs that hide amongst the boulders.
To stay warm, marine otters have to eat a quarter of their body weight in seafood every single day.
And things are particularly hard for this female because her cubs aren't yet old enough to hunt for themselves.
Before each fishing trip she rolls in seaweed, trapping air in her fur, so insulating herself from the chill of the seas.
The cold isn't her only challenge.
Being so small, these otters can only hold their breath for about a minute, making every dive a race against time.
This otter lives on a calorific knife-edge, often only getting enough from one hunting trip to fuel the next.
Success.
A meal for the youngsters.
These otters spend their entire lives at the coast, so they must accept its day-to-day challenges.
But coasts pulse to much more than just the daily rhythms.
On the shores of Alaska, a spectacular annual event is about to take place.
Each July, predators gather for the biggest feast of the year, but it will only last a few weeks.
Brown bears come down from the hills.
Wolves appear out of the woods.
And seals assemble in the ocean.
The coast is the only place where hunters from the sea meet those from land and air.
Bears have a sense of smell 2,000 times better than ours and can even detect prey out at sea.
They know the salmon are coming.
They also know the best fishing spots and are prepared to fight for them.
After years feeding out in the Pacific, the salmon are returning to spawn.
But before they head upriver, they must pause and modify their bodies to function in fresh water.
The young and overeager try to catch the salmon while they're still in the surf.
Those with experience are more patient.
After six months of starvation in a winter den, all this food is just too tempting for the youngster.
Wise old bears wait for the salmon to move into the river, where they know the fishing will be easier.
The incoming tide signals a change.
The experienced bears now take up their prized fishing spots at the mouth of the river.
The salmon are finally here.
As the fish are funnelled into shallower water, a seal gets its chance.
The wolves will have to wait.
Bears dominate the river-mouth.
These bears rely on the salmon run for nearly 90 percent of their year's food.
Most of the salmon make it upstream past the bears, but now they must run the gauntlet of wolves.
The salmon will sustain the wolves through the rest of the summer.
The sheer abundance of this seasonal bounty has made these bears the largest in North America.
Estuaries are the meeting place of rivers and sea, and they're vital staging points for migrating birds.
In Europe, each autumn, they're visited by millions of waders.
The birds are returning from their breeding grounds in the Arctic to overwinter in Africa, and are stopping off to refuel.
Knot can only feed when the mudflats are exposed.
At high tide, they're forced onshore where they must wait for the tide to turn and reopen the larder.
A peregrine falcon.
Young peregrines come to these estuaries in autumn to hunt waders.
Peregrines are the world's fastest aerial hunters, but this is a very challenging environment for a young falcon.
It's one predator faced with thousands of prey.
Flashing black and white, the swirling mass of wings dazzles the falcon's sensitive eyesight.
An individual target may be a better option.
A peregrine's plumage is not properly waterproof, so he can't afford to get his feathers wet.
He must flush his prey into the air.
But as soon as he gets close, the waders ditch into the sea where he can't follow.
Success depends on keeping his prey away from the water.
Now it's a dogfight at close quarters.
Peregrines only stay around estuaries for the few months the waders are there.
As soon as their prey leaves, they will head back inland.
Some animals come to the coast, not to feed but to have their young.
Patagonian sea lions.
These are just a few months old.
Sea lions can't give birth at sea, they must come to land to have their pups.
Each summer, thousands cluster in colonies along Argentina's Valdes Peninsula.
The mothers regularly return to sea to hunt.
But their young stay on the beach for they have not yet learnt to swim.
Orca.
Killer whales.
They come at exactly the same time each year to hunt the pups.
It's a narrow window of opportunity and the odds are stacked against the hunters.
Just like the dolphins, orca take great risks in leaving their natural habitat.
With every attack, there's a real danger of being stranded.
Orca can only hunt for a few hours each day, because at low tide a rocky reef blocks their access to the beach.
So until the tide is high, the pups are safe.
Early in the season the orca have one big advantage the pups are naive and don't yet recognize the whales as a threat.
But the young sea lions will learn quickly.
Silently, the killer whales move into position.
Less than half the attacks are successful and with each attempt, the pups grow wiser.
The orca's advantage is slipping away.
For the next few weeks, hunter and hunted are locked in a desperate race.
The orca to seize pups, and the sea lions to learn how to evade their attacks.
These young sea lions have triumphed.
They've learned to recognize the danger and evade the killers.
For the orca, the window of opportunity has closed for another season.
Newfoundland, Canada.
A unique seasonal event is about to transform this place.
It's the greatest coastal breeding spectacle on the planet, but it will only last a week or two.
Capelin.
Billions of them.
In early summer, these tiny fish mass just offshore.
The great shoals inevitably attract predators.
Humpback whales.
They've traveled over 5,000 kilometers from their breeding grounds in the Caribbean.
Nowhere else in the world do humpback whales gather to feed in greater numbers.
But no sooner have the whales arrived than the capelin do something apparently suicidal.
They deliberately cast themselves ashore, and, once out of water, they lay their eggs.
They're one of only two species of fish that leave the ocean to spawn like this.
A fish out of water is an easy meal.
But capelin go to these extreme lengths to give their offspring the best chance of survival.
For many, it's the ultimate sacrifice.
Cod.
Great numbers of them move in from deeper water to plunder this brief bounty.
Their impact on the vast shoals is small but as they hunt, the cod drive capelin off the seabed and up into the range of the waiting humpbacks.
The whales herd the fish against the cliffs.
Then they unleash a secret weapon.
These bizarre calls panic the capelin, driving the fish ever closer together, making them a more concentrated target.
This bonanza will disperse within days, so the humpbacks have to make the most of it while they can.
Hunters at the coast are always in a race against time.