Enjoy a full 50-minute documentary about Brazil's Amazon Rainforest 🇧🇷 📺 "Brazil – A natural History" Part 5: Flooded Forest
The Amazon Rainforest is the largest rainforest in the world, covering an astonishing 3.5 million square kilometers and home to one in ten of all known species. Dive into the Amazon Jungle and uncover its incredible secrets, from breathtaking Amazon species to astonishing survival strategies.
Meet the majestic harpy eagle, the world’s most powerful bird of prey, with talons larger than any other eagle and a talent for maneuvering through dense canopies. Witness the dazzling Cock-of-the-Rock as males compete with dramatic displays to attract females in a daily jungle spectacle. Explore the ingenious world of leaf-cutter ants, tiny farmers cultivating underground fungus by neutralizing toxic leaves. Dive into the flooded forest to encounter the pirarucu, a colossal fish, and the mysterious mata-mata turtle, both thriving in this submerged jungle.
From howler monkeys’ battles with bitter leaves to the sloth's slow-motion survival, the Amazon’s species reveal mind-blowing adaptations to life in this biodiverse paradise. Even the trees hold secrets, forming a delicate balance between life and survival. Get ready to explore the Amazon Rainforest secrets that make this jungle one of the most extraordinary places on Earth.
The Amazon, the greatest rainforest on earth. It is home for one in ten of all species.
It may look like a vast tropical paradise, but nothing could be further from the truth.
This is a landscape that is as much water as wood, and each year the two worlds collide
when the forest fills with water.
The Amazon is inconceivably vast. It covers an area of almost three and a half million
square kilometres. It is not a uniform landscape, but many, from lowland flood forest to upland
forests on dry ground. Within this green space, a huge number of animals strive to make a living.
Each morning, howler monkeys greet the day. They're advertising their ownership of a patch
of forest, but their calls alert a keen-eyed killer. The harpy eagle is the most powerful
bird of prey in the world, quite capable of carrying off a howler monkey. The harpy's wings
are broad and rounded, which allow it to manoeuvre through the canopy with deadly precision.
The harpy's legs are as thick as a man's wrist, and it has the largest talons of any eagle.
It can carry off prey the same weight as itself. But this time, the giant eagle's objective
was only a branch. The leaves are for the nest, which is in one of the tallest trees
in the rainforest. The fresh twigs may not be there to build up or decorate the nest.
The leaves of many plants in this forest contain chemicals, poisons, to stop animals eating them.
And these leaves may act as an insect repellent. The eagles could be deploying chemical weapons.
The uniform green of the Amazon hides many differences. There are terra firme forests
on high ground, and flood forests alongside the myriad rivers and lakes.
Many of the trees are engaged in a hidden war where they use chemicals for protection,
something the woolly monkeys might wish for, especially from insects. When not scratching,
the monkeys provide a service to the trees. Figs offer nutritious soft fruits full of small seeds.
As they feed, the woolly monkeys pass the seeds and so spread fig trees through the forest.
In the unseen war, the trees fight to keep their leaves. Many use poisons to stop animals eating
them, but at the same time encouraging creatures to eat their fruits. Most fruit is highly
nutritious, and this has helped shape the sex lives of one resident, the cock of the rock.
Each morning, after quickly filling up on fruit, the fabulously coloured males gather at a communal
display area, a lek. Each male owns a low-level perch, and below it a small patch of ground.
It is because they are fuelled by fruit that the males can spend most of the day displaying.
The males compete amongst themselves, trying to drive other males from their perches.
The arrival of a plain-coloured female, and the males descend to their individual areas.
Curiously, the males now stop calling and hardly move. They wait with all their feathers pumped up,
hoping the female will visit their patch. Males try to disrupt each other's displays, barging
into the scene mid-action. The female watches and assesses the quality of the males on offer.
The males use patches of sunlight to heighten their splendour. She has chosen a male on the
far edge of the lek, where mating discreetly takes place. The trees offer edible fruit as a
reward to animals that spread their seeds, but many put up a chemical shield to defend their
leaves from being eaten. There's an unseen war between the trees and leaf-eaters, and the most
important consumer of leaves in the Amazon is this small insect, the leaf-cutter ant. Its jaws
vibrate a thousand times a second as it slices through leaves. The cut leaves are not eaten by
the worker ants, for they may be toxic. Instead, the ants carry them back to the nest. As they
travel, the ants lay down a scent trail to mark the way. The chemical of pheromone is so powerful
that each ant produces only one billionth of a gram. The cut leaf can weigh 20 times the ant's
own weight, the equivalent of us carrying a one-ton load. More remarkable still, these mini-Hercules
range more than a hundred metres from their nest, the human equivalent of a 25-kilometre hike.
As if the load were not enough, smaller ants ride on the leaf, shotgun style, to protect the carrier
from parasitic flies. And flies are not the only danger. There is a fungus that enters an ant's
body, eats it, then grows its own mushroom from the dead ant to spread its spores to yet more ants.
The underground nest is huge, and may house as many as eight million individuals.
The leaves are taken to special chambers, where a different class of ant
cuts them into smaller pieces. The purpose of all this industry is to feed a fungus.
The ants are farmers, and the smallest kind of worker tends the fungus gardens.
This is the food for the colony. The ants and the fungus depend totally on each other.
If the ants bring leaves that contain chemicals that upset the fungus,
somehow it tells the ants, and they then gather different leaves.
The queen is a colossus in this Lilliputian world, and weighs 1,500 times more than the
small gardener ants. Only she produces the eggs that will turn into the many kinds of workers.
The colony is always busy, digging new chambers to grow more fungus.
The spoil is brought out and dumped.
The ants have found one method of dealing with toxic leaves.
Other animals have found different ways to overcome this challenge.
The mother sloth has her own way of finding edible leaves.
Very slowly. The reason for the sloth's famous lethargy is that leaves have little nutritional
value. So the sloth saves energy by a very low, slow metabolism. The sloth uses her fine sense
of smell to find leaves with little or no poisons. And the baby learns from its mother.
Movement is a real giveaway to a predator. But this is no problem for the sloth,
which rests and sleeps for much of the day. There is excitement at the nest. The eagle
chick has hatched. The mother will do most of the nest duties, shading the baby from the fierce
tropical sun. The chick will spend five months in the nest as it grows to the size of its giant
parents. In all that time they will bring in branches as insect repellent. The mother sees
something move. It's not the sloth, but a howler monkey. The monkey will be one of many that the
parents bring to their single chick over the coming months. Only the largest trees in the
can support the eagle's huge nest. And one of the bird's favorites is the Brazil nut tree.
It is a forest giant, and its fruits too are huge. The fruit weighs over two kilos,
and as the tree can grow to 50 meters, it has a long way to fall. There's even a record of a fruit
hitting and killing someone. The fruit is immensely hard, and for a long time it was a mystery as to
what animal could open it. But we know now that this rodent, the agouti, both eats the Brazil nuts
and helps produce new trees. The agouti's sharp incisors and powerful jaws chip away at the case,
but it takes a lot of patience and stamina before the rodent reaches the nuts inside.
The agouti eats some and buries the rest for later. Luckily for the tree, the agouti doesn't
remember where all its buried treasure lies. And so in the agouti, the Brazil nut tree has a
well-paid gardener that even plants its seeds. The large seeds can lie dormant for over a year
before they germinate. And the story doesn't end there, for there is another animal that
relies on the Brazil nut fruit. This is a kind of poison dart frog. The frog gets its toxins
from the ants and mites it eats, which in turn get the poisons from the leaves.
The frog concentrates the poison and advertises the fact with its bright colors.
The female frog lays her eggs on the damp forest floor.
The male guards them and keeps them clean. When they hatch, he gives them a lift.
The tadpoles stick to the mucus on the frog's back.
The frog carries the tadpoles one by one to empty Brazil nut cases.
He checks the miniature pond to see that it has enough food for the tadpole to eat.
In a couple of months, young poison dart frogs will emerge from the safe nurseries of the Brazil
nut cases. The Amazon forest is a tough place to live. No paradise. It is full of hidden poisons
and unpalatable plants that its inhabitants have to cope with. The howler monkeys must rest and
sleep for hours whilst they digest barely edible leaves. The night brings new challenges and a
creatures that tuck away out of sight during the day. And there are different fruits to be found
and consumed. The four-eyed opossum prepares for the night. It's an omnivore, a generalist.
It uses its sense of smell to find food in its dark world. But it has to compete with bats.
A large fruit is an irresistible attraction. The four-eyed opossum needs to move quickly if it's
to fend off the hungry bats. They are absorbed with feeding, but they must be wary of the opossum.
The allure of so much fallen fruit is too much. And once the opossum has left, the bats return.
They are in the grip of a feeding frenzy and fail to notice the opossum's return.
The Amazon is a world where much is hidden, where the trees offer fruits whilst defending
their leaves. A world of poisons where plants and animals fight an unseen war.
But for both plants and animals, there is one huge challenge. The Amazon is a rain forest.
As much as two and a half meters of rain falls a year. And most is concentrated in the wet season.
The trees and their leaves play a crucial role in the weather, for half the rain that falls
comes from the forest itself. The leaves naturally release water vapor, which then forms clouds
and returns as rain. The downpours are dangerous for the harpy eagle chick.
If the baby is drenched, it will chill and die. These are perilous times for the most powerful
eagle on earth. The rains transform the Amazon forest and its many rivers.
The water swells the rivers and as they rise, they begin to enter the forest.
The rainstorms are so intense that the forest becomes an amphibious world, halfway between air
and water. The leafcutter ants are in trouble. Their pheromone trails are washing away.
The ants are disoriented. Their highly organized world is disintegrating under the onslaught of
rain. And things are about to get even worse. It's not just the torrents of water from above.
The rivers keep rising, overwhelming the ants' trails.
The ants, the greatest harvesters of leaves in the forest, are swamped by the rainy season.
As the water rises, it spreads into the forest and creates some of the most unique
habitats in the world. The Varzias and Igapos, or seasonally flooded forests.
Almost a quarter of a million square kilometers of forest, an area three times the size of Austria,
is submerged. The transformation is total. Where once birds perched and agoutis fed,
there are now new opportunities. At its peak, the flood can reach over 20 kilometers into the
forest. The water is green with microscopic plankton, which feeds shoals of small fish as
they move into the flooded forest. The fish set up home amongst the leaves of the forest floor,
where ants once carried their heavy loads. This male rivulus is attracted by a female.
She is larger and sends out strong come hither signals, but all is not as it seems.
The male is enticed, but he is courting with death. The female was nothing of the sort,
but another species, Erythrinus, a fishy femme fatale, but mimics a female and so lures the male
to its death. As the water rises further into the forest, larger predators move in with it.
The mata mata lives on the front line as the flood pushes into the trees.
It has its own method for catching fish. Its technique is to blend into the background.
It looks like an old weed-covered log. Its disguise is so complete that fish nibble its shell.
This formidable predator's only limitation is that it must breathe air. This restricts the
mata mata to the shallow edges of the encroaching flood. The turtle settles down again and waits,
and then explodes into action. For most fish, the end is as unexpected as it is sudden.
The Brazilian name mata mata may refer to the turtle's ability to kill.
If so, it is highly appropriate. As the water fills the forest, it causes problems for some
of its slower inhabitants. The sloth faces the new challenge of moving from tree to tree
as it searches for the least poisonous leaves. The sloth is a surprisingly good swimmer.
Which is just as well. Mother and baby can swim, very slowly, the short distances between trees,
as long as their fur doesn't become too waterlogged. Curiously, the sloth's wet fur
may be a blessing in disguise, for it encourages green algae to grow, which provides a kind of
camouflage. As the water continues rising up the branches of the trees, a male splashing
charisin moves in and sets up territory, and it soon attracts a female. The male guards an
anonymous patch of water below a twig. The splashing charisins are unique among all fish
in laying their eggs on leaves above the water. The act of mating requires extraordinary
coordination and perfect timing. The reason for all this precision is that the fish's eggs are
safer on a leaf out of the water, away from hungry mouths. Once all the eggs are laid,
the male not only guards them, he also keeps them moist. The eggs develop quickly, and after two
days, the babies are ready to hatch. They drop safely into the waters of the flooded forest.
The water continues to rise. In the Amazon, it rains over 200 days a year.
All the animals of the forest have to live with the wet. The leafcutter ants are severely
handicapped by the rains, but their vast underground colony is in the terra firme forest,
safe from flooding. Even when the rains stop the ants gathering leaves, they have their
fungus gardens to feed them. Rain or no rain, there is always work to do. The smallest type of ant,
the minim, looks after the eggs and feeds the larvae. The underground city is vast.
There may be as many as 1,000 chambers, all tended by gardener ants and producing fungus for the
colony. The ants, with their intricate relationship with a fungus, have found a way past the chemical
defences of the trees. The agouti stays on higher ground, close to the Brazil nut trees and its
buried food supplies. The cock-of-the-rock too live on the higher ground. The males display all
year round, even in the rainy season. The males take exception to the agouti wandering through
their display ground. Like the cock-of-the-rock, the woolly monkeys prefer to eat fruit,
but it's not always available. In tough times, the monkeys select the youngest leaves,
for they're likely to be the least poisonous. Yet some trees fruit at this time, when they're
surrounded by hectares of water. The rubber tree seeds seem to be wasted, falling into the floods.
But nothing could be further from the truth. This fish, the tumbakui, swims below the rubber tree.
It has evolved as a specialised fruit and seed eater, with powerful jaws and teeth that can
crush the hardest seeds. The strange relationship between fish and tree is mutually beneficial,
for the tumbakui doesn't crush all the seeds. Those that pass through its gut are spread
throughout the flooded forest. At the height of the flood, the Varzia is not a safe place,
for the pirarucu, the largest fish in the Amazon, prowls its deep waters.
This monster can grow up to three metres long. The pirarucu is a strange giant,
for the fish rises to the surface every 10 to 15 minutes as it hunts, for it must breathe air.
The pirarucu is a member of a primitive family of fishes that has been stalking and terrifying
other fish since the age of the dinosaurs. And the pirarucu has a relative, another
dinosaur fish, that haunts the leafy, sub-aquatic world of the flooded forest.
It has a very different target, the small creatures that are stranded on the trunks and
branches of the flooded trees. At one metre long, the arowana is smaller than the pirarucu,
but no less frightening. The flood brings it closer to the treetops and its prey.
The floods are a time of plenty for the arowanas, for months they have access to the trees.
But all good things must come to an end. The waters begin to recede.
This is a dangerous time for the fishes of the forest. It is all too easy to be trapped in pools
and puddles, stranded as day after day, night after night, the forest dries out.
Many fish suffer this fate, but in the Amazon, one animal's misfortune is another's opportunity.
The four-eyed opossum takes the chance to add yet another item to its varied diet.
But not all the fish are helpless. As the pools empty, Erythrinus, the killer mimic,
simply swims over the ground. Gravity carries it downhill to the river. In this remarkable way,
it escapes certain death. Rivulus, too, has an escape strategy. It uses its powerful tail muscles
to launch itself into the air. In this strenuous way, it flips over the forest floor, eventually
arriving at permanent water. The temporary inhabitants of the flooded forests are forced
back towards the streams, rivers, and lakes. The pirarucu father guards his babies.
They hatched as the waters rose and have grown rapidly in the flooded forest.
Now the monster fish shows his gentle side, watching over hundreds of his babies.
They've already taken up the habit of breathing air, and that ability is crucial for babies and
adults alike, for the warm waters have very low oxygen. The babies will stay with their father
for three months. The male secretes a pheromone from his head, which keeps the young fish close.
They will grow to one meter long mini monsters by the time they are one year old.
Few of these babies will reach adulthood, but those that do will become the largest
freshwater fishes in South America, and terrors of the flooded forest.
The ebb and flow of the floods brings both feast and famine to fishes.
And the rainy and dry seasons affect all the creatures of the Amazon.
It's in the dry season, in the terra firme forest, that another giant of the Amazon
reaches a key moment in its parental duties. The harpy eagle brings a last meal to the nest.
It's five months old and almost fully grown. Over the long period in the nest,
its parents have brought monkeys and sloths, placed leaves to fend off insects,
and protected it from the rains. Now it's time to take to the air.
But first the chick must strengthen its wing muscles. The realm of the harpy eagle is one of
the most complex in the world. The trees hold the key to many of its secrets. They guard their
precious leaves with poisons, and those same leaves release the water vapor that in turn
produces the clouds that feed the most remarkable floods on earth.