Original subtitles

This is the Pantanal,

the Earth's largest tropical wetland.

It's home to a wealth of animals.

A wonderland sprinkled with jewel-like springs

and dense swamps.

It looks like a paradise, but there's a catch.

The fortunes of the animals that live here

are repeatedly reversed,

as every year, the whole region disappears underwater

and then dries out.

In the Pantanal, survival, even for the mightiest,

can never be taken for granted.

The Pantanal lies at the heart

of the South American continent.

It's a gently sloping basin

to the southwest of Brazil's highlands.

Rivers flow from the surrounding mountains,

creating a maze of woodlands,

meadows, rivers, and lakes.

At the end of the rainy season,

the Pantanal is full to overflowing.

This is an amphibious world,

and the creatures that live here

have to cope with the ever-changing landscape.

The largest rodents and otters in the world

depend on the wealth of these tropical waters.

The local crocodile, a jacare,

and the otters feed on the vast numbers of fish

that live within the rivers and lakes.

The giant otters fear nothing,

not even the top predator,

the jaguar.

It's South America's largest cat.

Powerful legs make it a strong swimmer.

And it's as much at home in water as on land.

The Pantanal is home to a surprising number of jaguars,

and they patrol the labyrinth of rivers

in search of prey.

But this cat is not hunting,

or at least, not in the normal sense.

It's a big male,

and he's entering the territory of a female.

Jaguars are solitary for most of their lives.

Males approach females with trepidation

for jaguars have the most powerful bite

in the whole cat family.

The meeting is an anxious affair.

The urge to mate

is in direct conflict with the instinct to fight.

Jaguar courtship is a rough affair.

Mating in these top killers is no simple matter.

The female both invites and rebuffs the male.

On this occasion,

the violent wooing doesn't work out.

The Pantanal is huge,

10 times the size of the Everglades.

As the weeks go by without rain,

the fierce tropical sun evaporates the water

and the rivers slowly drain the wetlands.

The water level falls, exposing the riverbanks.

The giant river otters take the opportunity

to advertise their territory

by scent marking the newly-exposed mud and sand.

The otters are a family and they work together

to spread their urine over the fresh mud.

It takes a mix of cha-cha-cha and disco

to ensure the bank is truly impregnated.

The family's particular smell

will leave no doubt as to who owns

this part of the Pantanal.

The majority of the rivers

that enter the wetland are large and murky.

As they meander, they deposit tons of silt and mud.

But there is another kind of river

that feeds the Pantanal,

a river with a very different character.

The water is crystal clear.

That's because it comes

from the surrounding limestone mountains,

bubbling up from underground

directly into the rivers.

Piraputanga patrol these polluted waters.

They spend a great deal of time

looking up at the trees that line the river.

They are the favorite haunt of capuchin monkeys.

The monkey's boisterous behavior dislodges insects,

which become mini Jonahs to the piraputanga whales.

The relationship between monkeys and fish goes further.

The fish keep an eye on the monkeys.

When the monkeys move off, the fish follow.

It's not just the falling insects

that the fish are after.

The monkeys are keen on fruit, including figs,

but they're not the tidiest eaters.

The scraps fall to the river,

where they're gobbled up by the piraputanga.

The fish are opportunists.

In fact, the piraputanga

are important to the trees.

Along with the monkeys, they spread the seeds.

The fish follow the monkeys for an easy meal.

But they're not totally dependent on the capuchins.

When the monkeys leave,

the fish have to fend for themselves,

feasting on the low-hanging fruit.

The piraputanga diet

is divided between fruit and meat.

And the fish even adjust their digestive enzymes

to suit the food they eat.

With such a wealth of fish,

it's no surprise there are predators.

The anaconda is South America's largest snake.

It can grow to over eight meters.

The snake is as much at home in water as on land.

And this one is looking for a meal.

The huge snake's eyes are cloudy.

It's functionally blind

as it's about to shed its skin.

But the anaconda uses its tongue even underwater

as it searches the puddles

in the limestone for catfish.

No luck, this time.

The limestone rivers, with their constant flow,

are the exception.

Elsewhere, our rivers are falling,

and the Pantanal is drying out.

Grass grows where once there were sheets of water.

The lakes are shrinking.

They are the sight of a strange performance.

Jacare males display their strength

by raising their heads and tails clear of the water.

The vibrations produce infrasound.

This carries through the opaque waters

to the nearby females.

Jaw snaps and head slaps

produce higher frequency sounds

that are easier to pinpoint

and allow the females

to find the male of their choice.

After all the bravado,

the actual mating is a gentle affair,

with a female approaching

and rubbing up against her chosen mate.

The capybaras watch the performance

from a safe distance.

They are the largest rodents in the world.

Males can weigh over 50 kilos,

and these adult capybaras dwarf the young jacare.

The dry season is the hardest time for capybaras.

They grub around in the mud for old water weeds.

Their urge to eat

is greater than the need to avoid the jacares.

Both jacare and capybara

must keep an eye out for their greatest enemy,

jaguars.

The male still bears the scars

of his last amorous encounter.

Now that the land is emerging from the floods,

the old jaguar can roam far and wide

in search of another mate and to hunt.

The waters have fallen over a meter

and are still dropping.

The lakes are draining down to pools,

and the pools are emptying into the rivers.

It's now that the hyacinth macaws breed.

The Pantanal is a stronghold for this rare bird.

At a meter long,

it's the largest flying parrot in the world.

The macaws pair for life,

and the couple take time to groom each other.

This is thought to increase the bond

between the two birds.

Hyacinth macaws feed on the nuts

of the Mucuja and Acuri palms.

The parrots have to be big,

because to open an ultra-hard nut,

they require a huge beak

and large, powerful jaw muscles.

The macaws have their nest in a taruma tree.

It's a true survivor.

And at 40 years old,

it has witnessed many a drought and flood.

These huge parrots

need a tree of this size for their nest,

but big trees are rare,

just like the hyacinth macaws.

The chicks grow quickly

on a diet of protein-rich palm seeds.

Even so, it takes around a hundred days

for the babies to reach a size

when they can leave the nest.

For all that time,

the parents must bring them palm seeds.

By the time the chicks are able to fly,

the dry season will be at its height.

The rivers are at their lowest,

and steep banks are exposed

by the falling water level.

The giant river otters are excited.

The family is composed of the parents

and their offspring of different ages.

The parents bring out the new babies

for their first taste of water.

Curiously, for such aquatic creatures,

the babies have to learn to swim.

They have many keen coaches

in their older brothers and sisters.

After a hesitant start,

this baby seems to be getting the hang of it,

though buoyancy is still an issue.

The older otters keep a watchful eye

on the beginners.

The babies still appear unconfident and anxious.

It'll take a while yet

before they're truly water babies.

Reassurance is needed.

The jaguars are not a problem for the adult otters,

but they could kill a baby.

But they're engrossed in a slow

and very careful courtship.

The male takes no farther part in parenthood,

and the female will give birth alone

in three months' time.

As the water continues to drain away,

the fishing gets easier for the otter family.

They hunt as a pack.

The fish are concentrated in the rivers.

Adult giant river otters

eat around three kilos of fish a day.

Catfish are high on the otter menu,

as they are slow swimmers

and tend to stay in once place,

and so are easier to catch.

Easy to catch,

but not so easy to eat.

The catfish erects and locks its spines,

making it too much of mouthful for the anhinga.

The otters quickly fill their stomachs

and the family set out to patrol

their patch of the Pantanal.

They have strength in numbers,

and they seem frightened of nothing.

Even a jaguar holds no fear

There are few, if any, records of a jaguar

killing an adult giant otter.

And the jaguar is no match

as long as the otters stay in the water.

The heat of the dry season is beginning to tell.

The black vultures are just irritating pests.

The heat is getting to all the animals.

The otter family hides from the midday sun.

When the heat gets too much,

they take to the relative cool of the water.

The young ones have grown, but they're still pups,

and they want to play.

In most of South America, jaguars are nocturnal,

but in the Pantanal,

the big cats roam in the full glare of the sun.

They'll even hunt in the heat of the day.

The otters are not their target.

Jaguars search out their victims by moving slowly

and using their near perfect camouflage.

But most times, the prey gets away.

The jaguar attacks from cover,

sneaking up behind its target.

It's quite capable of ambushing animals

larger than itself.

The jaguar has the most powerful bite of any cat.

It crushes the skull of its victim

and paralyzes it.

The jacare will feed the jaguar for several days.

In the unrelenting heat,

the water continues to evaporate,

leaving dry land and muddy pools.

The jacares are concentrated

in ever-smaller pockets of water.

They have eaten all the fish here.

They must leave soon

or become casualties of the dry season.

The situation is unbearable.

Only in the cool of the evening

can the jacares make their escape.

These reptiles are not designed

for long distance travel.

Their sprawling gait is inefficient,

but they have to search out new ponds.

This jacare must find a new waterhole soon

or die of exhaustion.

The jacares only have the hours of darkness

to discover a new, less crowded home.

By the morning, some are still searching,

but most have found new homes.

For the moment, some of the pools still hold fish.

The respite for the reptiles is temporary,

for the Pantanal continues to dry out,

and the pools become more and more scarce.

Parts of the Pantanal look more like a desert

than a swamp.

The water is evaporating evermore quickly

in the intense heat.

What were lakes are now mere puddles.

The fish are trapped,

struggling to breathe in liquid mud.

They're hunted down by jabiru and wood storks.

The birds use their feet

to feel for the fish in the opaque waters.

The jabiru stab where they sense the fish.

The wood storks have a different technique.

They sweep their bills though the water,

waiting for the touch of a fin or scale.

What is a calamity for the fish

is a bonanza for the birds.

This is how the topsy-turvy world

of the Pantanal works.

Many of the fish are eaten or entombed in mud,

but some fish survive in the rivers

and the few lakes that remain.

And things are about to change.

After months of drought, the Pantanal transforms.

Rain is already falling in the surrounding mountains,

and now it arrives in the Pantanal itself.

The water spreads out over the vast plain.

This is one of the wonders of the natural world,

the periodo de cheias, the flood.

It turns an area the size of Britain

into a myriad world.

The water will rise more than two meters

and it will stay like this for months.

The jaguars are as much at home

in this new water world

as they were in the dry season.

The rising waters have dislodged a casualty

of the dry season.

Not all the jacares made it to safe havens.

Full of gas, one becomes a floating restaurant

for the black vultures.

The waters push into the meadows.

This is the time of the fish.

The survivors move into the flooded grasslands

and feed on the many drowned insects.

The fish are spread out over thousands of hectares.

They're hard to find.

For the birds, fortune has swung from feast to famine.

Many leave the Pantanal altogether.

The fish quickly put on weight.

In this time of plenty, females produce eggs

and males begin to fight and court.

A male pike cichlid excavates his nest burrow.

The female will lay her eggs in the nest,

and the male fends off other fish,

for one fish's eggs can be another's food.

Peacock bass have laid their eggs amongst the grass

and nervously patrol the area.

Like the pike cichlids, they are highly aggressive,

and they need to be,

for the eggs are a tempting target.

A piranha has made its nest

in a hollow in the flooded grasses.

It stands guard against the circling predators.

But it is soon overwhelmed by numbers.

Even a piranha's fearsome teeth

are not enough to frighten off the egg thieves.

The good times for the fish last a few months,

and then rivers begin to fall

and the water starts to drain away

from the floodplains.

This is a dangerous period for the fishes,

for they can easy become trapped

on the floodplains.

The fishes and the jacares

hurry back to the channels that lead to the rivers.

Those animals that do not make it back to the river

face an uncertain future in the lakes

that will form in the dry season.

The Pantanal is ever-changing,

and the fortunes of its animals

shift with the rise and fall of the waters.

The fish flourish in the wet season,

but suffer with the drought.

For the jacares and fish-eating birds,

the opposite is true.

The fate of the animals of the Pantanal

is inextricably linked to the seasons.

Most capybara babies

are born as the waters fall away.

They are excellent swimmers from an early age.

The young capybaras are born into a social group,

where all the adults protect them.

Capybaras are ever-watchful,

for they have many enemies.

While the adults keep watch, the young feed.

They can suckle from any of the mothers in the group

and do so indiscriminately.

They will drink milk

for the first 16 weeks of their lives.

The young ones are the most vulnerable,

and they need to stay close to the adults,

but curiosity leads them to explore.

The adults keep a constant lookout.

The jaguar is one of their greatest enemies.

The big cat can attack from land and water.

The threat is spotted.

The capybaras head for the supposed safety of the water.

In the confusion, the young are scattered.

The capybaras regroup,

but one baby

is missing.

The Pantanal is a land of feast and famine.

Here, every creature's fate depends on the season,

and one animal's loss is another's gain.