The Hardest Challenge The Hunt

The duels between hunters and hunted

are as dramatic as any event in the natural world.

The stakes could not be higher.

For both, it's a matter of life and death.

Yet, surprisingly, it's the hunters that usually fail.

To have any chance of survival,

predators must be perfectly tuned to their own hunting arenas.

Every habitat brings a different challenge.

This series will reveal, as never before,

the extraordinary range of strategies predators use to catch their prey.

But even for the most skilful...

..success is never guaranteed.

SCREECHING

SNIFFS

BARKS

BARKS

BARKS

BARKS

A female leopard on the prowl.

Few predators instil more fear.

SNIFFS

Yet, out in the open,

she has little chance of catching anything.

To succeed, she must get within a few metres of her prey...

undetected.

Her strategy is to use cover,

wearing it like a cloak of invisibility.

She's an expert in stealth.

Impala are her favourite prey.

This one is just out of her range.

SNIFFS

She needs to get closer, within four metres.

She only has a short burst of speed.

She must stay hidden until she's in the strike zone.

TWIG SNAPS

But out of sight doesn't mean out of mind.

Impala have acute hearing and a superb sense of smell.

SNIFFS

Now the only prey she can see is right out in the open.

But leopards are the most versatile of all the big cats,

adept at finding cover in the most unpromising places.

The steep walls of the gully are now her cover for an ambush.

The male puku is close enough, but he's too big to tackle.

She needs to slip past him without being seen.

If he spots her, he'll blow her cover.

SNIFFS

Slowly does it...

To succeed here,

she needs to find prey grazing close to the edge.

Or better still,

in the gully itself.

Frustration.

Success would have staved off hunger for a week.

But while there's prey around, there's hope.

Peeking over the top is a risk,

but it's the quickest way to find a new target.

SNIFFS

A burst of speed of 40mph

and it's all over in less than six seconds.

Except...it isn't.

Dazed and disorientated,

the impala makes a miraculous escape.

It's been the perfect stealth hunt

and she's nothing to show for it.

But then, six out of seven leopard hunts end in failure.

A leopard's hunting strategy depends on finding cover.

But how do you catch your prey

in a place where there's literally nowhere to hide?

That's the challenge facing Zambia's wild dogs.

This close-knit pack is made up of one adult female

and her 12 offspring from last year.

Unlike the solitary leopard,

wild dogs depend for their survival on teamwork.

Dogs that play together...

work together.

Each morning, the pack heads out across the open plain,

prospecting for prey.

Mother decides which direction they go.

The rest stay close.

They'll keep going for miles until they find the right kind of prey.

Adult zebra are too big a challenge.

And the same goes for tsessebe.

An oribi is an easier target.

But is it worth the effort,

especially on an oribi that's as fit and bouncy as this one?

Better to save their energy for something bigger.

A wildebeest.

It's what they've been looking for.

The dogs need to make the wildebeest run.

Their success will depend on wearing him down in a long chase.

While the prey's running, the dogs have the advantage.

But when the wildebeest stand their ground, the tables are turned.

Faced with a wall of horns,

the pack is powerless.

But not all the wildebeest have had the courage to stop.

Now the real contest begins.

The wildebeest are big and strong.

But the dogs have stamina.

Right now, hunters and hunted are clocking 40mph.

The pack can keep this pace up for miles.

The wildebeest can't.

One wildebeest peels off.

Then another two.

The split confuses the inexperienced pack,

sending them in different directions.

The mother and one youngster continue on.

The rest of the pack stop, believing they have an easier target.

It's a mistake.

Like a beast with two heads, each bull protects the other's rear.

And the dogs can do nothing.

Ahead, the chase continues.

Another wildebeest peels off.

Now the mother has just one in her sights.

But it will mean nothing without the help of the rest of the pack.

The situation here has reached stalemate.

The young dogs have lost valuable time.

They must try and catch up with their mother.

Back at the front, the mother is beginning to tire.

And the wildebeest knows it,

bouncing to show he's still strong and not worth chasing.

But fresh, young legs are catching up fast.

When one dog tires,

there's always another member of the team to take up the lead.

The dogs now have the numbers to bring the wildebeest down.

Each bite risks a broken jaw,

but going for the legs is the only way to stop it.

And they must do so before it reaches the safety of the herd,

a few hundred metres ahead.

After a 20-minute chase, the bull's energy is near spent.

This time there will be no sanctuary within the herd.

The dogs' stamina has been rewarded.

All they must do now is to bring their quarry to the ground.

Working as a pack

allows wild dogs to take on prey ten times heavier

than any one of them.

But many mouths need a lot of food.

The price they pay for these numbers

is knowing they'll have to attempt the same thing again tomorrow...

and every day.

Teamwork and stamina on Africa's open plains

have proved to be a winning combination.

But in the dense and complex world of the jungle,

hunting is a never-ending game of hide and seek.

Here, it pays to sit still...

..and blend in...

..because you just never know who's watching.

The Parson's chameleon is an expert

in the see-and-not-be-seen game.

It lets its eyes do all the work...

..while the rest of its body moves in slow motion,

so as not to scare possible targets.

The problem is that it can only see prey if it moves.

So is this a stick insect...

..or a stick?

Ah-hah...

Time to unleash its secret weapon...

..a tongue longer than its body.

The Parson's close cousin, the nasutum chameleon,

has the same weapon, but in miniature.

As small as a matchstick, he needs to get much closer to its prey.

But even with eyes as big as its stomach,

this isn't the meal deal he was hoping for.

In the jungle, it's hard finding the right-sized prey

when you're a tiny predator.

Promising opportunities

can quickly turn to disappointment.

Spotting any kind of prey in this dense, green world

is hard.

If you do find something, you want to make sure it doesn't escape.

The praying mantis has arms

that can strike ten times faster than a blink of the eye.

And it's the only insect known to see in 3D.

Perfect for judging strike distances.

But like the chameleon,

her problem is seeing prey when it freezes.

She needs some movement to be sure it's food.

Just the tiniest sign of life.

Yep, that's done it.

The lightning strike has given her the edge over her insect prey,

but it doesn't pay to be complacent.

In the jungle arms race,

only too often there's someone else with a more powerful weapon.

And there's one predator that has, perhaps,

the most ingenious answer of all to the jungle's challenge.

It lives along rivers in the rainforests of Madagascar.

The insects it hunts fly down the same jungle corridors.

But there's a problem.

It's a web-building spider.

So how does it get over the river to hunt?

It's called Darwin's bark spider

and the female has a remarkable strategy.

Like a real-life Spider-Woman,

she sprays strands of silk in one long, continuous flow.

The threads fan out like a sail

and drift on air currents blowing across the water.

Every few seconds, she crimps the strands together

to stop them spreading too widely.

The breeze will do the rest,

blowing the threads into a single line and a 25-metre bridge.

Now she must reinforce her bridge, because her web will hang from it.

But there's something bouncing the line at the other end.

Another Darwin's spider is trying to take advantage of her hard work.

She must deal with the intruder head on.

The cut line is an inconvenience,

but no more than that.

With hooks on the tips of each leg, she gathers in the thread.

It won't go to waste, as she'll eat it later.

When it's all reeled in, she sprays again.

Out streams another 25-metre bridging line.

How a spider, no bigger than a thumbnail,

can produce so much silk so quickly

has baffled scientists.

And it's no ordinary silk.

It's the toughest natural fibre on the planet,

tougher than steel.

And it needs to be tough to span the wide river.

With the bridge taut

and the ground anchor in place,

it's time to construct her trap.

These spiders can build the world's largest orb webs,

up to two metres wide.

A few hours from the first spray of bridging line,

the job is done.

Now her strategy is simple...

..sit and wait.

And there's one final bout of silk production...

..shrink-wrapping her food for later.

Not all rivers provide their predators

with a steady supply of prey.

On the Grumeti River in Tanzania

lives the planet's most patient predator.

A Nile crocodile.

Five metres long,

700 kilos

and very hungry.

His last square meal was nearly a year ago.

The river's other residents aren't food...

..just a distraction.

He is waiting for something bigger

from over the horizon.

But beyond the big croc's isolated river,

there's still no sign of the migratory herds

he depends on for survival.

Other, smaller crocs are waiting, too...

..but their meal ticket depends on the hunting skills of the big guy.

The herds could be here in a week, or a month.

In rare years, not at all.

Until then, the crocs must conserve their energy.

GRUNTING AND MOOING

Finally, the sound they've all been waiting for.

The herds have arrived.

It's time for the crocs to get into position.

All eyes will be on the big guy.

Only he has the power to tackle a full-grown wildebeest.

The year-long wait is almost over.

After months on the march, the wildebeest are desperate to drink.

But experience has taught the adults to be cautious.

The water is just too inviting for a calf,

unaware of the dangers within.

But every wildebeest must take its chances...

..and hope that its reflexes are faster

than what many know lurks in the murky waters.

Just a harmless hippo.

That was no hippo.

It's put the wildebeest more on edge.

But here, fear always gives way to thirst.

Catching the wildebeest is all about timing.

The big croc's technique is rusty.

It's been a whole year since his last hunt

and he's out of practice.

But this isn't the end of the drama, just an intermission.

For the next two weeks,

waves of wildebeest will pass through the Grumeti.

Time for the big croc to try a different tactic.

The floating log.

He's hoping the wildebeest won't notice him until it's too late.

Now the smaller crocs move in.

The big croc will need their help to tear off chunks.

Crocs can't chew, so they have to spin together

to tear pieces off the carcass.

Everyone gets their share...

..and it's all thanks to the big guy.

He won't feed again until the wildebeest return next year.

Across the globe, millions of animals are continuously on the move

in search of seasonal food.

But it's not just prey animals that must migrate.

Some predators have to journey, too.

Amur falcons are one of the world's greatest long-distance travellers.

As their prey dries up in their breeding grounds in Siberia,

they embark on an epic migration to Southern Africa,

crossing 14 countries, two continents and one ocean.

Only here, in this remote valley in northeast India,

do they join forces.

A million falcons

and the greatest gathering of birds of prey on the planet.

This valley is a vital pit stop on the falcons' migration.

The tiny raptors can go no further

until they build up their fat reserves...

..and they've timed their arrival here perfectly.

For just a few weeks each year, winged termites, alates,

leave the safety of their mounds in millions.

High in calories, these alates are exactly what the falcons need

to fuel their oceanic crossing,

the longest made by any bird of prey.

To have any chance of surviving their journey,

they must nearly double their weight in just two weeks.

Those that make it to South Africa

will have to do the whole trip back again in four months' time.

For Amur falcons,

survival means flying 14,000 miles every year of their lives.

For some predators, it's not the distance they have to travel

that's their greatest challenge,

but the size of their prey.

And few challenges come bigger than the one in this ocean.

Each year, female humpback whales

journey from their feeding grounds in Antarctica to Australia

to have their calves.

These calm, warm waters are a perfect nursery.

Perfect, but for one thing.

Orcas, killer whales.

They appear just as the migration begins.

And they're on the hunt for calves.

Highly intelligent, orca are the ocean's most successful predator.

When hunting, they can travel at 30mph...

..twice as fast as a mother and calf.

The hunters close in silently.

It's only now that the mother realises they've been followed.

The orca have the advantage of numbers,

but they need to be cautious.

The mother's rear is protected by a five-metre-wide tail

that could slice through them.

Her flanks are defended by a pair of long, barnacle-covered flippers.

And in the middle is the calf,

riding high on its mother's back and out of reach.

To separate mother from calf,

the orca must use all their intelligence.

They take it in turns

to try and wave wash the baby away from its mother.

In a month, the calf would be strong enough to withstand the onslaught.

Not now.

But then the tables are turned.

A male humpback arrives, driving the orca away with its flippers.

And the situation worsens when a second male appears.

Now the pod face the power of three 40-tonne whales,

and the escorts make their weight count.

The bubbles are like a smokescreen,

blocking the orcas' vision and sonar.

There's a real danger of being injured

by an unseen fluke or flipper.

With the escorts defending both sides of the mother,

the killer whales have been outmanoeuvred.

As the orca retreat, the escorts drive home their advantage,

pushing the hunters further away.

It's an error of judgment.

With mother and calf unprotected,

the orca double back before the humpbacks can react.

The killer whales separate the calf from its mother.

They push the calf underwater

and drown it.

The intelligent hunters have turned defeat into victory.

The orcas' prize is so large that sharks are quick to take advantage.

Through intelligence, stamina and teamwork,

the orca have mastered the ocean's greatest challenge.

Yet even they fail as often as they succeed.

Most predators fail most of the time.

It's what makes them the hardest-working animals

on the planet.

The pressure is even greater when they have other mouths to feed.

At eight months old,

these cubs are still totally dependent on their mother.

To support them she must kill something large, like a gazelle,

nearly every day.

But these youngsters are proof

that she has overcome the challenge of their habitat.

Few cheetah mothers get this far with four cubs.

If the cubs are to survive without her,

they must watch their mother carefully

and learn the strategies for hunting on the open plains.

There's a lot to take in.

They'll need to learn

that their top speed can only be sustained for a few seconds.

They'll have to master how to match the twisting turns of the prey,

so they get close enough to trip it.

And they will soon learn the margin for error is tiny.

The odds are against them.

90% of cheetah cubs

never make it to their second birthday.

Even with this experienced mother,

the future for this family is far from certain.

All any predator can do is to keep on trying.

For The Hunt team,

filming a Nile crocodile capturing a wildebeest

would require the same skill, patience and reactions

as the five-metre reptile.

The timing of the shoot would also be critical,

since this behaviour only happens

when the crocs' river is at its lowest point.

But things get off to the worst possible start -

the river in flood in the middle of the dry season.

What we hoped for was that the Grumeti River

would be just a series of pools

full of crocodiles.

They're probably scattered over 30 or 40 miles of river.

So we've got to wait for two things -

the crocs to bunch up and the wildebeest to come.

As well as Mark, this small crew includes son Jacca

and camerawoman and wife Vicky.

Are you keeping watch?

I am. I'm watching my son and my husband

in a very deep, muddy river with lots of crocodiles!

You could lose a large part of your family here if you're not careful.

Yeah. Basically, half of us could be wiped out.

These crocs hunt by stealth

and they can sneak up in this dark, murky water

right to the edge of the bank.

So the golden rule of filming here

is to be one metre from the water.

Not to be outdone by the floodwater,

the team sets up the first hide.

But any idea of filming is soon swept away.

Literally, within half an hour, an hour,

I felt water around my ankles.

If I was still in that hide, then he definitely wouldn't be on the bank.

We're not going to go in and get it.

The water the colour it is

and knowing that he's got friends around,

who could be literally just at the base there.

With a flooded river and no wildebeest,

the wait was going to be longer than expected.

Crocs are used to being patient.

But now we've got to show equal patience.

Leaving the raging river,

the team go in search of the migrating wildebeest,

to see just how far they are from the Grumeti.

I think we should go over the other side

and then we'll get a sense of the number.

-Should be up here. Do you want to take the controls?

-I'll take the controls.

It's some time before they find the wildebeest

on the Serengeti's vast plains.

-Loads there.

-Loads?

-Yeah, spread all the way across...

-Oh, OK!

Fantastic. How far away are we?

70 miles away.

Still a long way from the Grumeti,

but at least the wildebeest were heading in the right direction.

MARK TALKS INDISTINCTLY

The wildebeest are still a long way away

but, in the meantime, we can hopefully pick up

these intimate moments with these really huge crocs.

Finding the biggest and most dominant croc

would be key to the team's success.

Only the top croc would be powerful enough to grab a wildebeest.

To find their star,

Mark and Vicky would need to look out for territorial behaviour.

Today it's sunny and it's early in the morning.

I'm full of hope.

But at the end of the day, all Mark sees is one static croc.

He lay on the sandbank all day, I guess, seven hours.

Urgh! Patience.

And Vicky wasn't having much luck, either.

When we first found it, there were crocs all over the bank over there

and now I've been in here several hours and there's not one.

After a week,

Mark and Vicky are no closer to finding their dominant croc.

But at least the news on the wildebeest was more positive.

34 miles. Getting closer.

Back on the river, it was like Groundhog Day.

Crocs are all-or-nothing creatures.

And I'm afraid it's been another day of nothing.

With no sign of any action, the hours of watching motionless crocs

were beginning to take their toll.

It's like watching paint dry.

Well, that was useless.

Utterly useless.

The crocs just didn't come.

The team needed something to change

and the falling water seemed a good omen.

This is what the floodwaters left us - the lower jaw of a croc.

And look at that. I mean, it's...it's heavy.

This has come from a croc who must be at least five metres.

And they're down there.

Don't step too close to the water, sweetheart.

I got too excited by the jaw!

And with the water dropping,

excitement was finally rising amongst the crocs.

Well, that felt so different this morning.

It really felt like there was an energy there...

..that hasn't been there for weeks.

And it isn't long before the team find their dominant croc.

The big territorial male, who we hope will do most of the hunting,

has been very active this morning.

He's been displaying, really patrolling this stretch.

With a big croc to focus on,

all they needed now were the wildebeest.

Mark and Vicky take to the skies to check on their progress.

Look, right as far as you can see...

-The crocs might actually get a meal.

-That's great, Vick.

The wildebeest were, at last, less than a day away from the Grumeti.

Mark and Vicky take up positions on either side of the river.

-WHISPERS:

-We can see wildebeest

just trying to come down,

but they're just so nervous.

After such a long wait, it's a tense time.

Success for crew and croc

will depend on split-second reactions.

For the big croc, the first session ends in failure.

It's very easy to have empathy for the animals that are being hunted,

but I have to say that, in this instance...

..my sympathies are all with the crocs.

We've just seen how, over the past month,

they've had nothing to eat at all

and that's been what they've experienced for the last year.

And it's a few days before the wildebeest return.

It's 12 o'clock.

Very hot, but I can hear the wildebeest again.

There's a baby going in a bit further.

Come on...

Something's got to happen.

Yeah, now he's right out there.

Croc's right there next to him.

Oh, God, you can see the croc underneath the surface.

You can just see the swirl and just the dark shape.

And there he goes! Oh!

Urgh!

And he missed him again.

Yeah, at this time of the year, it's absolutely crucial for them.

If they don't feed now, then they're in dire straits.

Oh, here they come.

Thirsty innocence.

Come on, guys. That's better.

Come on, you can do it.

Got two there now, coming down on their knees next to them.

Come on, you can do it.

Just one footstep further out.

That's all that croc needs.

Oh, yeah, yeah.

Go on...

There he goes!

Well, that was amazing. I mean, just...

It suddenly happened.

Trying to work out where the crocs were underwater was a nightmare!

That was so intense.

One minute, there was nothing.

And the next minute, the bank was covered in wildebeest and then...

one was taken.

But I got it!

Next time, the hunt is on in the frozen north,

the High Arctic.

One of the toughest places on Earth in which to make a living.

To succeed here, a predator must exploit the few good times...

..to endure the bad.