(tranquil music)
When winter descends upon Europe,
many animals have no choice but to leave.
The migrations of many discrete creatures
have been a mystery until now.
And yet they cross oceans and deserts,
brave intense weather,
and travel thousands of kilometers unabated.
Thanks to recent scientific progress,
we are finally able to follow their journey,
and discover the secrets behind their incredible migrations.
(tranquil music)
Eleonora's falcon is one of the most iconic birds of prey
in the Mediterranean region.
(dramatic music)
Shortly after the birth of its young,
it undertakes an extraordinary journey
towards its winter home in Madagascar.
Deserts,
rough seas,
storms, nothing seems able to stop it.
This remarkable 10,000 kilometer journey
takes it from the Mediterranean to the Indian Ocean.
(dramatic music)
Makares Island in the middle of the Aegean Sea in Greece
is home to a large colony of Eleonora's falcons.
(engine buzzing)
At the end of August, Greek ornithologist, Nikos Tsiopelas,
visits the island daily to track the colony's evolution.
He's been studying their migration for 10 years.
While most migratory birds head towards Africa in September,
Eleonora's falcon only begins its journey a month later.
As summer comes to a close, insect populations,
which are at the heart of the falcon's diet,
begin to dwindle,
and yet this is exactly when the falcon chooses
to raise its young.
I can see at least two falcons flying over the cliff.
They look like their hanging.
(tranquil music)
Towards the end of summer,
a new source of protein becomes available
for falcons to hunt and feed to their young, sparrows.
Coming from the countries in Northern Europe,
these delicate birds make a pit stop in the Greek islands,
before continuing to Africa,
where they will spend the winter.
Unfortunately for them,
Eleonora's falcons await them as they make their migration.
(birds calling)
The Eleonora's falcon is mainly an insectivorous species.
It eats insects almost nine out of 12 months of the year.
But it shifts its diet
in order to provide its chicks with protein.
It's far more nourishing than the insects,
and that happens in late summer and during the autumn,
when the migration is at its peak.
(birds calling)
So, every morning the falcons are getting high up in the sky
and create a huge network of birds
in the northern side of the island where they breed,
so it's a net that is waiting for the migrant passerines
to come towards the island.
(birds calling)
Although they normally hunt alone,
the migration period prompts the falcons
to adopt a group strategy.
(dramatic music)
They form a line to collectively stake out
any migratory birds.
Once their prey is in sight,
all they need to do is dive down to catch them.
This invisible net makes it impossible to escape.
The passing sparrows can't avoid the trap
that has been laid.
It's an easy hunt.
Eleonora's falcon
is the only bird species in the Mediterranean
that has shifted its breeding season from spring to autumn
in order to get advantage
of the current of migrant passerines.
(birds calling)
Within an Eleonora's falcon family
the father usually takes care of hunting.
After having his fill,
the male passes his prey onto the female.
(chicks squawking)
The eggs take about one month, 27 days to hatch,
and then it's another month, more or less,
for the chicks to fly, and leave the nest.
(birds calling)
A couple usually gives birth to two fledglings.
In order for both to develop properly,
each needs to eat at least two sparrows a day.
Without this minimum supply of protein,
the chicks would not have enough reserves
to complete their own migrations.
(chicks squawking)
The Eleonora's falcons are breeding colonially.
The colony may be really dense
in places where the nesting sites are less,
so they have to pack up in smaller areas,
but they can be loose colonies,
in the island where you can find many, many good nests.
This provides the falcons with the ability
to fight off enemies and rivals
that are much bigger than them,
because they act socially, in groups.
(tense music)
Makares island also attracts
other birds of prey, like the booted eagle.
These birds compete with the falcon colonies for airspace,
and the amount of prey available.
(dramatic music)
The falcons work together as a group
to hassle the eagles and chase them away.
The booted eagle has no choice but to hunt elsewhere.
(tense music)
This defense system is what guarantee's the falcon colony
enough sparrows to feed all of their young.
(falcon calling)
For now these chicks still depend on their parents for food.
(chicks squawking)
But their first feathers are already visible,
and in less than three weeks they'll leave the nest,
and learn to fly on their own.
The Columbretes Islands in Spain
are another gathering ground
for a colony of Eleonora's falcons.
(tranquil music)
(falcons calling)
A few weeks have gone by.
The frail fledglings have grown into juvenile birds,
as evidenced by the bright-colored plumage on their torsos.
Soon they'll take off on their own without their parents
for their very first migration.
(tranquil music)
Ugo Mellone is an ornithologist and a wildlife photographer.
He's working on a project that tracks Eleonora's falcons
in an attempt to discover the secrets
behind their migration.
(falcons calling)
We are here to catch a juvenile
in order to apply a satellite transmitter,
so we have to find a suitable individual that is old enough,
enough big and old, to place the transmitter.
Yes, indeed, I just can see an adult
going inside the nest with the prey,
so probably that is a nest down there.
For the last 10 years or so
the scientists have placed tracking devices on the falcons
to follow their migrations.
Last year they installed a transmitter
on a five-year-old adult named Rossi.
(exciting music)
Rossi first crossed two ecological barriers,
the Mediterranean Sea, followed by the Sahara Desert.
He then flew over the African continent,
all the way to Madagascar,
an impressive 9,000 kilometer journey,
wrapped in just four weeks.
Rossi's trajectory matches the itinerary
followed by most adult falcons.
They already know the way,
because they've undertaken the trip several times before.
The juvenile falcons, however,
will be making the journey on their own
for the very first time.
Scientists want to know more about their itinerary.
We want to place a satellite transmitter
on a juvenile Eleonora's falcons,
because it will be very interesting to see
how an unexperienced juvenile bird
can accomplish such a long trip.
Oh, yeah.
Yeah, the adults fly from the nest,
so it's a good time to go and check the nest.
(dramatic music)
Ugo Mellone needs to act quickly.
He needs to capture the young bird
and place the transmitter before the parents return.
Placing a transmitter on a falcon is a delicate task,
so Ugo has asked a colleague to help him.
Vicente Urios, a professor at the University of Alicante,
has mastered the technique.
I got one!
We'll be able to place it.
Male or female?
Female.
Look how beautiful she is.
(falcon chirping)
The scientists cover the young falcon's eyes
to reduce her stress level during the procedure.
(speaking in foreign language)
She's huge!
Be careful she doesn't bite you with her beak.
I'll hold her.
Vicente Urios places the transmitter
like a small backpack.
He carefully stitches the straps together,
avoiding the falcon's feathers.
There, that should hold.
The procedure is painless,
and the transmitter is attached in a way
that won't limit the falcon's movements.
That's good, yeah?
(falcon chirping)
Keep it straight.
That's perfect.
Okay, I think we can put her back now.
Yeah, let's go
(tranquil music)
The transmitter is in place.
This small device will allow the scientist
to monitor the young falcon's every movement via satellite.
Ugo Mellone will hence be able to track its position
from an ordinary computer.
That's good, right?
Yes, that's good.
All right, good to go.
Ugo named the young falcon Ana.
(speaking in foreign language)
She'll soon be two months old.
In a few weeks Ana will be ready for her flight to Africa.
I can see that the transmitter is working properly.
Yes, indeed I can see here that Ana is still on the island,
and is moving just there close to its nest.
She probably will leave the island in a couple of weeks.
She need now to learn how to fly properly,
and to prepare for the long travel to Madagascar.
(waves crashing)
The time to take flight has not come yet.
(tranquil music)
Many young falcons like Ana
are still discovering their own bodies.
Others are ready to undertake their first flight.
They take wing,
while their parents oversee the learning process.
(falcons calling)
Eleonora's falcons migrate mainly by flapping flight,
even if some soaring flight is also involved,
if the conditions allow it.
They make use of wind,
especially when crossing ecological barriers.
The allow to be drifted by the wind
in order to accomplish the crossing as soon as possible.
(tense music)
An Eleonora's falcon reaches adult size
when it hits adolescence.
Small and light, they are only 40 centimeters long,
and weigh 400 grams on average,
yet their wings can reach up to one meter across.
In comparison to the birds' bodies, that wingspan is huge.
The force of their flapping wings
is far superior to that of other soaring birds of prey,
allowing the falcons to reach speeds
up to 80 kilometers an hour.
Weeks have gone by.
September is coming to a close.
(tranquil music)
All adult falcons have already left.
The juveniles are now fully independent.
They know how to fly and hunt,
but they remain on the island to build up their reserves.
(tense music)
Ugo decides to wait for Ana to leave.
For the moment
his young protege is still perfecting her flying technique.
(computer beeping)
But in a few days she'll be ready.
And as soon as wind conditions are optimal,
she'll take flight.
A few days after her parents leave,
Ana is finally ready for her long journey.
(tranquil music)
Like all Eleonora's falcons,
she'll undertake her extraordinary migration
of thousands of kilometers completely alone.
Now it's Ugo's turn to leave.
He's decided to follow Ana to Africa,
a journey he'll also be taking for the first time.
(lively music)
Thanks to the Argos transmitter,
he hopes to follow the path taken by the young female.
The data provided by Rossi
shows that he mostly traveled south.
Ana seems to be taking the same path.
Like all juveniles,
Ana instinctively heads south,
even though she's never made this journey before.
How did these birds of prey,
no matter their age or experience,
know how to orient themselves?
(doors rattling)
It's not so light. (laughs)
Nikos meets with Andre Murard,
a seasoned air pilot.
On the grass. -: He's trying to understand
how Andre determines his location while in flight.
The ornithologist is hoping he can compare
the pilot's techniques to those used by the falcon.
(engine buzzing)
(tranquil music)
Do you see the bird, no? (laughs)
No.
What about navigate, about always, where are you, roughly?
When I see the sky,
the east is there, west is left, north, and south.
Okay, so more or less you know where you are.
I follow the landscape.
This little town is Yenne.
I see, this mountain
is La Dobichale.
With this type of plane we're obliged to fly
only when we can see the ground.
For the bird, they are more or less the same.
They get to know the topography.
They have landmarks, they know mountains,
they can follow rivers, the know coastlines.
With an eye, they have the ability,
determine their position from the air, (speaks unclearly).
Another very, very important, I think it's the sun.
They can navigate
with the angle of the sun in relation to the bird,
so they don't use one each time,
they use the combination of all those things,
in different proportion.
(engine buzzing)
What if there's no visibility?
What if it's night, or if you have heavy cloud?
(Andre speaks unclearly)
We have the compass, and we can see we are north.
We can find many similarities with airplanes,
like the compass.
Proven that birds can feel the magnetic field of the Earth,
and moreover, not only feel the magnet itself,
but they have probably some
special cells in their eyes
that can create lines along the magnetic field,
and they can see lines around all over the Earth.
(falcon calling)
(dramatic music)
When Eleonora's falcons begin their migration,
they use the Earth's natural magnetic field
to orient themselves.
The Earth behaves like a large magnet,
with two opposing magnetic poles.
The vertical lines that connect the north to the south
represent the magnetic field
generated by the Earth's liquid metal core deep underground.
This magnetic field provides
a precise north-south orientation,
that coincides with the rotation axis of our planet.
In order to migrate in the right direction,
Eleonora's falcons use a combination of tools,
visual memory, a solar and celestial compass,
and the Earth's magnetic field.
These tools ensure the birds migrate in the right direction.
(dramatic music)
Ugo has arrived in Mali,
on the border between the desert and the Sahel.
He discovers an ecosystem which seems ideal
for falcon rest and recuperation.
Accompanied by his guide, Usmain Samaseko,
Ugo settles in for a few days,
in the hopes of seeing Ana.
(tea splashing)
The bird we are talking about
is very difficult to see here, because they fly here,
but they fly on a very broad front.
I suspect that in this, in the whole Mali,
at least 3,000, 4,000 Eleonora's falcons
pass every migration in one month,
but to see one is very difficult.
(glasses clinking)
You like? -: Best thing after a day
like this one.
Thank you. (laughs)
(tranquil music)
Ugo nervously pulls up the latest saved data
from Ana's Argos transmitter.
He sees that the young falcon managed
to cross the Mediterranean without a single stop.
Eight hours after leaving the island,
she reached Africa near the Algerian coast.
But now she has to tackle the Sahara Desert.
The desert is an ecological barrier.
That means an area where they cannot forage,
and where any weather change
can be very hazardous for their survival.
Therefore they try to overcome it as soon as possible,
flying sometimes also during the night.
For Ana quickly crossing the Sahara Desert
is a matter of survival.
She'll have to overcome its sheer immensity,
in addition to the infernal temperatures.
(dramatic music)
Strong headwinds, sandstorms, exhaustion,
none of these are in Ana's favor,
and yet her instinct to migrate at all cost,
an innate part in every Eleonora's falcon,
drives her onward.
Four days have passed,
and Ugo was still waiting to find out
if Ana survived her Sahara crossing.
(tranquil music)
(computer beeping)
Okay, very good news.
Ana completed successfully
the crossing of the Sahara Desert,
and now is enjoying this new habitat, the Sahel,
which is very productive,
because we are just a few weeks
after end of the rain season,
and there are a lot of insects
with which Ana can replenish its energy stores,
and continue the migration towards the Madagascar.
(exciting music)
Like Rossi before her,
Ana successfully crossed the Sahara Desert,
without stopping, and in just four days.
It's an incredible achievement,
considering the immensity of this sand barrier,
over 2,500 kilometers wide.
But Rossi chose to fly much farther east than Ana.
His migration experience must've taught him
to take a more direct route to Madagascar.
The young female has once again become an insectivore
in the Sahel.
After a few weeks of rest in Mali,
she has replenished her reserves,
and resumes her migration.
Since the beginning Ana has been heading south,
but suddenly she radically changes direction.
Her transmitter indicates she's now going directly east.
What caused this sudden change in course?
Ana went south when she left the Columbretes Islands,
guided by the Earth's magnetic field,
her solar compass, and celestial navigation.
But that's not all.
Ornithologists have shown
that the direction and length of the flight
are programmed in these birds' genetic code.
Scientists call this vector navigation.
This is what allows falcons to know
in which direction to fly, and for how long.
This explains how Ana, after flying south for six days,
knew she needed to change course and head east.
This extraordinary tool is useful for all falcons,
but vital for juveniles
making the very first migration of their lives.
It enables them to instinctively know the way,
without having traveled it before.
The transmitter continues to track Ana's movements,
revealing more differences
between a young falcon and an adult.
It only took Rossi three weeks
to reach Madagascar from Nigeria.
In the same amount of time Ana has only made it to Sudan.
Adults already have experience on navigation, on hunting,
and therefore they got enough fuel,
enough fat stores before the migration,
in order to accomplish it with very few stopovers.
On the other hand, juveniles are less able to feed,
and therefore they will move
according to the distribution of local resources,
sometimes for very few tens of kilometers for each day.
(tranquil music)
(lively vocal music)
Ana continues her migration,
and begins to fly at a faster pace.
Ugo explores the ecosystems
that she crosses along her journey.
Ugo stops to pull up Ana's latest position.
Once again the data reveals some surprising information.
(computer beeping)
After arriving in Kenya,
Ana once again sharply altered course towards the south.
(dramatic music)
On the regions near the equator,
the Earth's magnetic field is weak.
According to Ugo, even though falcons can use
the sun and the stars to orient themselves,
this weakness in the magnetic field
forces Ana to use other directional guides
to make precise course corrections.
(falcon calling)
For adults, we believe that the geomagnetic information
is less useful when crossing the equator,
and therefore we can speculate
that Eleonora's falcons use also other cues,
for example also the landscape's characteristics,
the positions of some big mountains,
such as for example the Kilimanjaro.
(elephants rumbling)
However, the juvenile Eleonora's falcons
are traveling across an unknown landscape,
because it's the first time, the first migration for them.
Maybe they can use even infrasounds.
(tranquil music)
Infrasound is defined
as any low-frequency sound that falls
outside the limit of human hearing.
Infrasounds can be created by things like storms,
or the wind simply blowing on a mountain.
These sound waves can travel thousands of kilometers.
Eleonora's falcons are believed
to have the ability to detect them.
According to certain scientists it's these infrasounds,
combined with solar and celestial navigation,
that convince juvenile birds to change course.
This would explain why Ana suddenly branched south.
(elephant grunting)
So, probably infrasounds create a landscape,
a vibration landscape, that can be sensed by some species.
In this kind of landscape, big landmasses,
prominent topographical feature, can trigger huge changes
that can be detected by these birds.
So definitely, infrasounds could be among the answers
to resolve this mystery of the orientation
of juvenile Eleonora's falcons.
(tranquil music)
The invisible network
created by these mysterious infrasounds
could explore how young Eleonora's falcons
orient themselves confidently in unfamiliar territory,
especially if magnetic information is sparse.
(children yelling)
Since leaving Mali,
Ana crossed Africa from west to east in four weeks.
After passing Cameroon,
the Democratic Republic of the Congo, and Sudan,
she flew over Lake Victoria.
Ana is now over the great Serengeti plains of Tanzania.
(tense music)
(falcon calling)
Only 46 days after leaving the nest,
Ana arrives in Mozambique, where insects abound.
But the area also attract many other raptors,
reducing the amount of prey available to the falcons.
Ana will have to quickly be on her way again
towards her final destination, the island of Madagascar.
(engines whirring)
Ugo decides to wait for Ana
on the northeast side of the island,
where Rossi finished his migration the previous year.
Eleonora's falcons can be found
all over the island of Madagascar,
but according to observations by local ornithologists,
this is the part of the island
where Ugo has the best chances of seeing them.
Birds of prey tend to settle within primary forests,
which are difficult to access.
Ugo meets with Armand Marozafy, an experienced local guide.
(speaking in foreign language)
He spotted falcons a few days ago
in a distant part of the forest.
Hello. -: Hello.
I'm Ugo. -: Yeah, yeah, I'm Armand.
Welcome to you. Nice to meet you.
Here is Leon. -: Ugo.
Here is Gino. -: Nice to meet you.
Okay.
(computer beeping)
So, like I told you, I am studying Eleonora's falcons.
As you know, the best area in Madagascar
for wintering Eleonora's falcon
is just here in the northeast, in this area.
So, I don't know if it's possible to reach just this area,
or to go at least in the nearbies to check this area.
I think there are possibility to see the falcons.
Yeah, yeah.
Since you wrote me email,
when I took other people here, I check,
and there in valleys, I have seen one couple,
and then in the other place,
also I have seen the other couple.
Sometimes between, not only to that place,
but in some area also, they flying when they hunt.
Hunt something, like a dragonfly, or like cicadas.
Ah, cicadas, ah, yeah, yeah, yeah, that's great.
So okay, so we can start today already.
Yeah, yeah, yeah.
(dramatic music)
From here we have to take a boat.
We have to bring our own food, we have to bring our tent.
There is a lot of water?
Yeah, and her, some something, but we need her,
and we, we'd camp for her,
in the place where we could find when is here.
(tranquil music)
The boat is faster than traveling by foot,
and it saves the team an extra day of travel.
But it will still take many hours to reach the area
where Armand spotted the falcons.
(tense music)
Ugo has never observed Eleonora's falcons
anywhere outside the Mediterranean.
In such a sea of vegetation,
the odds of him spotting a falcon are low.
(animals calling)
Ah, that one is, um...
Ah, wait, wait, wait, wait, wait.
Ah, you see, there, the red ruffed lemur.
Ah, there it is.
They live in groups,
of, for example, between three, until eight, one group.
Most of the time the female are the leader,
the leader of the group.
(animals calling)
Yeah, he's moving very quick.
Okay, let's go.
(tense music)
To increase their chances
of spotting an Eleonora's falcon,
Ugo and Armand must find a clearing.
In such a dense forest, these open spaces
are ideal hunting grounds for birds of prey.
Finally we are arriving.
This is the place where we are going to camp.
They must set up camp quickly.
Here the seasonal rains fall daily, and in abundance.
They have to stay alert,
as a falcon can appear at any moment.
(bird calling)
Ugo won't have a lot of time to study it.
(animals calling)
(fire crackling)
(men speaking in foreign language)
Thank you. -: Yeah, yeah.
You can share it.
So tomorrow, is it okay for you if we meet at,
I would say, half past five?
Half past five, it's okay,
because bird, we have to go wake up very early morning.
It's difficult to see them,
because they occupy a big region,
I mean, on the northeast of Madagascar, so even if the,
almost, the whole world population comes to this region,
they move across a big range
in order to search for their preys.
Can you guess how many Eleonor falcon in Madagascar,
during the winter? Well,
it seems there are,
I mean, the world population is around 14,000 birds,
so I mean, also considering the juveniles,
maybe 40,000 and 50,000 birds coming every year.
Every year in Madagascar? -: But I mean,
these are just estimations, we cannot be sure.
(dramatic music)
Look, look!
Yeah, yeah, yeah, yeah, yeah, it's him, it's him!
It's him? -: Yeah, yeah, yeah, yeah.
Wow!
It's a girl, or another bird?
Yeah, it's a dark mouth, it's an adult.
Can you see? Yeah, yeah, yeah, yeah.
I see the beak.
Even without binocular, I can see the beak, little bit.
Yeah, okay.
(falcon calling)
Oh, she's gone.
(dramatic music)
Now it's going there to the right.
Now, now, yeah, yeah, yeah.
I think-- Yeah, yeah.
Yeah, yeah, yeah, it's here.
It's gone behind the ridge.
Oh, yeah, yeah, yeah.
But I think we can remain here,
because this falcon was here.
It means maybe it's a suitable area,
so maybe we can see more.
It's interesting, because here is an open area.
I mean, it's a second-growth forest,
and it's very close to the primary forest.
Probably the primary forest
is somehow a source of food for Eleonora's falcon.
(wings flapping)
So, they take advantage of a so-called spillover effect
of preys escaping the forest,
and they hunt in these open areas.
In this open area.
How do you think about the threat?
'Cause here, you talk about open area in the forest.
For example, in Madagascar we have deforestation,
and so on. Ah, yeah, yeah.
On the short term, it may seems contradictory,
but deforestation may even advantage Eleonora's falcons,
because it's creating these open areas,
but I think that in the long term,
this is completely deleterious.
(tense music)
In Madagascar,
rampant deforestation is threatening the very existence
of part of the island's primary forests.
The population soared from 15 to 26 million inhabitants
in just 20 years.
For sustenance, the Malagasy are transforming the forests
into rice paddies at an alarming rate.
If something happens here in Madagascar,
it will have a effect
on the whole population of Eleonora's falcons,
so we can do whatever action to save the species
in the breeding areas in the small islands,
but if something is happening here,
all our efforts will be useless.
(birds twittering)
(tranquil music)
For now, Eleonora's falcons
that successfully complete the journey to Madagascar,
can enjoy the mild local climate.
It's still too early to evaluate the effects
deforestation will have on the falcon population.
Back at camp, Ugo pulls up the latest Argos data.
Ana just left Mozambique, and is on her way to Madagascar.
I am a bit concerned, because there is an hurricane
moving across the western part of the Indian Ocean,
so I hope that Ana will not have to cross the area
interested by the hurricane,
because it could be very dangerous
for a bird like an Eleonora's falcon.
(falcon shrieking)
(thunder rumbling)
(rain splashing)
(computer beeping)
Okay, very good news,
because Ana crossed the Mozambique Channel
without major problems.
And I am very happy for this because we can say that
she overcame the most difficult stage of his entire life.
Usually among migrating birds,
the first migration is the moment in their life
when the mortality risk is highest.
(tranquil music)
While up to 50% of the juveniles
don't survive their first migration,
Ana's efforts were victorious.
After 47 days of intense traveling, over 13,000 kilometers,
she has finally made it to her destination.
(tense music)
Ana took three weeks longer than Rossi
to get to Madagascar.
She stopped to feed a lot more often,
and struggled to orient herself,
but overall, her first migration was still a success.
(waves splashing)
Yet, in spite of all the new transmitter data
collected by scientists, certain questions remain.
So, among the many mysteries
that still we have to solve as a scientist,
concerning the movements of Eleonora's falcon,
I would, I liked maybe,
the one concerning the orientation system
used by juvenile birds, because really, as far as I know,
there are no other birds
performing alone their first migration,
and reaching such a restricted wintering area,
moreover, located on an island.
(tranquil music)
Six months have passed.
In the Columbretes Islands,
Eleonora's falcons are back in force.
(dramatic music)
The start of summer kicks off mating season,
and although they traveled alone,
the falcon couples are reunited to reproduce.
Some females are preparing to lay their eggs,
while other nests contain eggs that are ready to hatch.
They'll soon release young falcons,
that will in turn fly to Madagascar.
They'll be the ones undertaking this incredible journey,
carrying on the age-old Eleonora's falcon tradition.
(falcon chirping)
(dramatic music)