Original subtitles

Narrator: They're the stuff of nightmares.

Giant snakes of immense strength.

With a strike faster than the blink of an eye.

[hissing]

African rock python's...

A battery of finely tuned tracking sensors...

The better to find you with.

Rows of razor sharp teeth...

The better to grip you with.

Gigantic... Ancient... Aggressive.

[chicken squawking]

This is squeeze, an eight-year-old rock python

Propelled by the same primordial needs that drove her ancestors

In the days when dinosaurs walked the earth.

She can hunt in any terrain... At any time of day...

For virtually any prey.

But, squeeze is a mother, so others depend on her too.

... And bringing her young into the world safely

Is no walk in the park.

♪

There will come a time when she has to choose

Between her survival and theirs.

13 feet long... 70 pounds of muscle...

Squeeze is covered in the yellow, chestnut

And brown splotches that help her blend in

With the environment.

She hasn't eaten in two weeks. For good reason.

She's carrying a clutch of just-developing eggs.

She can't eat a big meal - not while they're gestating inside.

But she's hungry; a snack would be just the thing.

Something that in her sluggish state might not require

A lot of work.

She waits for nightfall.

Like most snakes, the rock python has poor vision,

But that doesn't mean it can't find you.

Squeeze can sense body heat - with incredible accuracy.

The scales on her lips have “pit organs”

Which are full of heat-sensitive receptors.

Nerves carry signals from the receptors

To the brain where they're converted into images...

Like goldilocks, squeeze is looking for something

Just the right size.

Not too small... A frog is hardly worth the effort.

Not too big... It would be hard even for a rock python

To swallow a cow.

But here's something just right.

This rabbit has come to dine on some tasty cabbages.

Unfortunately for the rabbit, the cabbages...

Are perfect cover for squeeze.

The rabbit's acute hearing is legendary.

But it seems oblivious to the approach of this stealth hunter.

[rabbit breathing]

♪

Rabbits are fast. Squeeze is faster.

[rabbit screaming]

Slowly, she squeezes.

Every time the rabbit exhales, the coils tighten

The python can move both sides of its lower jaw

To create a larger entryway, and in goes the rabbit, headfirst.

[snake breathing]

Strong muscles push the food down towards her stomach.

♪

When it's all in, time for a siesta.

In a safe place.

It takes a lot of energy to digest a whole rabbit -

She'll be very sluggish for a few days.

A sluggish snake is a vulnerable snake.

Pythons have lived in africa for millions of years,

Long before humans arrived on the scene.

Species come and go,

But the python has a talent for survival.

The snake we see today has changed little

From its prehistoric forebears...

Its among the world's most primitive snakes.

♪

The small thorn-like projections on their lower body,

Known as pelvic spurs, are thought to be vestiges

Of a time when these animals had hind legs.

A pair of hind legs might actually come in handy

Right now, as she's weighed down by the eggs inside her.

They've grown to the point where it's hard to make much progress.

Each egg weighs about as much as a billiard ball.

That's around 50 billiard balls

She's been hauling around for weeks.

[water flows]

[birds chirping]

She's ready to lighten her load,

But she can't just dump them anywhere.

[leaves crunching]

She's been searching for the right spot for weeks.

This hollow at the base of an old silver oak tree

Could provide shelter from the elements,

Hide her eggs from predators,

And keep them at a constant temperature.

♪

For an animal capable of such massive displays of power,

She can be surprisingly maternal.

She arranges her eggs in a pile and coils around them tightly.

Of all the snakes in the world, the african rock python

Is one of only a few that actually cares for its young.

All the others simply lay or give birth and leave.

Without her protection,

Squeeze's eggs would be easy pickings for monitor lizards

And mongooses.

She'll stand guard for the next 90 days,

Leaving the hollow only to bask in the sun

And return to warm her eggs with her re-heated body.

Every day she grows a little weaker...

And a little less able to defend herself...

... And her young.

Narrator: Several months have passed,

During which squeeze's only job has been guarding

And incubating her young.

She's weak from lack of food,

But her maternal instinct beckons...

Finally, inside the burrow, there is a stirring.

♪

[squishing]

A young rock python takes its first breath.

[squishing]

And then another python.

And another.

One by one, they say hello to the world outside their shells.

♪

They taste the chemical cues in the air -

Danger... Food... Mother.

They're not yawning because they're sleepy.

These yawns are a kind of snake calisthenics:

They align the jaw in preparation

For swallowing large prey.

For three months, the egg yolk provided them

With everything they needed to grow

Supplied by their umbilical cord.

This life line will be gone in a matter of hours,

And they will soon be hungry.

At only 20 inches long,

It's hard to imagine them as the mighty constrictors

Some will become.

But they don't have the luxury of waiting until they're bigger.

They have just a few weeks, to leave the nest,

Shed their first skin, and make their first kill.

Of the 35 eggs squeeze laid, 31 have hatched.

As the roiling mass of newborn snakes struggles

Toward the exit, the weakest are crushed

And never make it out into the world.

Out there the odds of survival will be even worse.

Some will die of starvation...

And others will survive just long enough

To become someone else's dinner.

Only a lucky few will make it to their first birthday.

For now, though, hope springs eternal.

The young pythons survey the burrow, searching for a way out.

Finally, one of them makes a break for it.

Squeeze keeps her hatchlings close for up to two weeks.

It might not seem very long to us,

But to these young snakes, it's a godsend.

Few predators will move on a hatchling when its watchful,

13 foot mother is coiled nearby.

It's a kind of parental care we don't associate with snakes,

But the rock python seems to be

An intriguing exception to the rule.

♪

But even squeeze has her limits:

If she doesn't feed soon, she could starve.

And when she slithers off for good,

Her offspring will be on their own - ready or not.

And the forest is full of watchful eyes.

Narrator: An adult african rock python is an apex predator;

It has little to fear from other animals in the wild.

But the same cannot be said of hatchling pythons.

They have many enemies, including venomous snakes -

Like the forest cobra -

And birds of prey - like the african goshawk.

♪

Their mother can't protect them forever.

Her maternal instinct has over-ridden hunger.

She's eaten nothing for months.

Now it's time to say goodbye.

It's time to hunt.

Not so long ago, squeeze broke out of her eggshell

And emerged from a nest

With many other hatchling rock pythons, just as her young did.

Most of the others in her clutch - maybe all - are long dead.

They starved to death before they could learn

To hunt successfully...

Or they were picked off by hungry carnivores...

Or they were killed by humans,

Either out of fear or for profit.

Every year there are fewer of her kind.

But squeeze crossed the finish line into adulthood

And is now a formidable and experienced hunter.

She knows where the food is, and she knows how to get there.

She laid her eggs deep in the valley.

Now she's going to have to climb this steep cliff face.

Not easy for an exhausted giant constrictor.

But here's how you do it.

♪

First anchor your mid-section to the rocky surface

Using the scales on your underbelly.

Then pull your tail all the way up to the anchor point,

Release the anchor, and use your tail, to push your way up.

Anchor, pull; anchor, push.

Repeat as needed.

[rocks falling]

It's grueling work, but hunger is a powerful motivator.

♪

She's not called a rock python for nothing.

Unfortunately, this is where things get a bit trickier.

Squeeze is an all-terrain predator.

She stalks the savannah, forest and cliffs.

Climbing trees? No problem. Fording rivers? Piece of cake.

She's bigger, stronger and faster

Than just about any other animal here,

So there's no place she can't hunt with impunity.

No place... Except here.

Here she's encroaching on the territory

Of another formidable killer.

Some farmers appreciate the animal

For keeping rats under control.

But many others fear it.

Farmers won't hesitate to kill one

If they see it as a threat to their livestock.

[rooster clucks]

Squeeze has to be very careful here.

She knows there are humans around.

But she also knows that where there are humans,

There's usually food.

[chickens clucking]

Visiting this chicken coop is like shooting fish in a barrel.

The hens know something's a little off,

But it's not like there's anywhere for them to go.

It's a calculated risk: Can squeeze swallow a chicken

And make her escape before the farmer finds her.

Every minute she's here

Is another chance for her be discovered.

And if the farmer discovers her,

The same cage that makes the chickens sitting ducks

Will make her one as well.

Despite the danger, she moves in slowly.

Methodically. Silently.

♪

[chickens screaming]

The entire strike takes less time than the blink of an eye.

About 50 milliseconds.

She accelerates toward her victim

With an impact 30-times the force of gravity -

If we did that, we'd pass out.

Her curved, razor-sharp teeth cut through muscle easily

And hold the chicken steady as she coils around it.

The rest is a foregone conclusion.

[chickens clucking]

She can feel her prey's heartbeat, and when it stops,

She knows it's over.

But she doesn't eat her kill just yet.

After not eating for months, one chicken just isn't enough.

[chickens screaming]

[chickens screaming]

She listens to make sure the coast is clear.

Once she starts eating,

She won't be able to make a quick escape.

[squishing]

[heavy breathing]

You'd think that stuffing her mouth with a chicken

Would make it impossible for her to breathe,

But snakes are able to extend their windpipes

Outside their mouths so they can breathe

And eat at the same time.

She'll absorb almost every part of the chicken, even the bones.

The feathers will pass through her system

And come out in her feces.

Not much nutrition in feathers.

[birds chirping]

Squeeze has had a good few months.

She's laid her eggs and guarded her offspring

Until they hatched.

She's managed to slip into a busy farm,

Eat two chickens, and slip out unnoticed.

Not so easy for a predator her size.

Now she's looking for a safe place to digest her meal.

But in this valley, safe is a relative term.

♪

Squeeze's young are now a month old.

Over the last few weeks

Many of them have gotten picked off by predators.

These are the survivors.

Now, it's make or break.

[birds chirping]

They have a few years to go

Before they are big and strong like their mother.

Until then, they're on everyone's menu...

And some of their bigger cousins aren't above cannibalism.

Narrator: As the young pythons' senses sharpen,

They're learning how to use them...

Not just for hunting... But for survival.

This is the forest cobra.

The largest and one of the most deadly cobra's in africa.

It may be a distant relative, but it's got to eat too.

The question is: Does this young python know the danger it's in?

Apparently so.

The cobra won't be easily fooled - this isn't its first rodeo.

One whiff of baby python and the jig is up.

Looks like the young python dodged a bullet.

Now back to the hunt.

Success will depend on doing a few things right.

First find prey of an appropriate size.

[sniffing]

Then, approach patiently and in complete silence.

[sniffing]

♪

[squeeling]

The strike was perfectly timed and right on target.

Just one small problem. A dental problem.

[squeeling]

The young snake's teeth,

Designed to hook onto prey and prevent it from escaping...

Are still too puny to get the job done.

[squeeling]

[breathing]

Better luck next time.

Meanwhile, not far away, one of his brothers is trying his luck.

[sniffing]

He tastes the air for the mouse's location.

♪

♪

[squeeling]

[rustling]

The mouse is held fast.

Let the coiling begin.

It's a big step for this young rock python.

All it means, though, is that he'll survive a little longer.

He'll need many more meals like this,

Before he grows to be a giant like his mother.

Squeeze is recovering from her long fast.

Rock pythons can go for long periods without eating,

Which is one reason why they've been around for so long.

But they also know they need to make hay while the sun shines.

It's autumn.

And as far as squeeze is concerned, the sun is shining.

Many of the valley's animals have given birth -

Including the impala.

The grassland has become a nursery.

These young calves weigh about 45 pounds,

And they don't know enough to be afraid.

Which they should be.

For squeeze an impala calf would be a perfect meal -

Heftier than the chickens and rabbits she's been subsisting on

- And without the risks of the farm.

If she bags one, she won't need to hunt again for months.

But adult impala are skittish

And have extremely sensitive hearing.

One wrong slither and the herd could easily bolt.

Narrator: The silent hunter...

And a species perfectly adapted to the art of escape.

The impala combines incredible agility and leaping power

With a sense of hearing attuned to the slightest sound.

Squeeze can smell to some extent through her nostrils,

But her most powerful sensory tool is her forked tongue.

The tongue is split in two,

Each side called a tine is connected to its own organ

In the roof of her mouth.

When it flicks out, the tines separate as much as possible,

So that each one sends slightly different information

To its respective organ.

Her brain then interprets these signals

As a “stereo” image of what's out there,

Which lets her track the distance

And direction of her prey.

♪

Stealth, not speed, will get her close enough to strike.

It's the only way to avoid tripping the alarm.

[rustling]

♪

[grunting]

The struggle lasts only a few minutes,

[squeezing]

Our eyes may sometimes be bigger than our stomachs,

But that's really not a problem for an african rock python.

Her lower jaw splits in two,

Allowing her to stretch around the impala.

Squeeze's skin is so elastic it can stretch

To more than five times her normal girth.

As amazing as this is,

Swallowing prey this size is a huge risk.

It will take her 45 minutes to do it —

45 minutes in which she couldn't move if her life depended on it.

[squeezing]

To speed things up, her metabolism climbs

To 44 times its normal rate and her heart gets 40% larger -

So it can pump blood faster to her digestive system.

[birds chirping]

[breathing]

At last.

45 pounds of pure protein, in one sitting.

It's a miracle she can move at all.

Now squeeze's body can spring back into shape.

She clicks her jaw back into position.

This meal will take her up to two weeks to fully digest.

But once she does, squeeze won't need to hunt again for months.

It will bump up her chances of survival for the year to come,

And ensure she's in peak condition

For the rapidly approaching breeding season.

When it all begins again.

♪