Think of African elephants and most of us will picture open savannah
where the largest land mammal mingles with lions, giraffes and gazelles.
In fact, a third of Africa's elephants live here...
in dense, dark rainforests.
Forest elephants stand just two metres at the shoulder, are more
slightly built and have pinker tusks than those on the savannah.
Little else was known about them until one remarkable woman began eavesdropping on their lives.
Andrea Turkalo is no ordinary scientist.
By living alone in remote jungle, she's learnt more about these hidden giants than anyone else on earth.
This has placed a huge burden on her shoulders.
Forest elephants are now under greater threat than their savannah cousins.
But Andrea could be in a unique position to help them.
She's learnt their language and understands what they're thinking.
She can even hear when they're in trouble.
Incredibly, she believes that, if we listen carefully enough, they might tell us what they need to survive.
The only thing most scientists see of forest elephants is what they leave behind.
Counting dung piles has been the crude way of guessing how many there are.
Their real secrets are hidden away in the vast rainforest that stretches over the Congo Basin.
But, in a small corner of the Central African Republic, there is a window into their lives.
This is Dzanga Bai.
A vast natural clearing...
and a Mecca for forest elephants.
The forest provides all the food they need,
so what is it that draws them out of the shadows?
The clearing contains a vital ingredient that's lacking in their diet.
Volcanic rocks lie close to the surface, and the salts they contain
neutralise toxins ingested with rainforest leaves and bark.
Generations of elephants have come here to prospect for these minerals and settle their stomachs.
Blowing down, they churn up the mud, then take a mouthful of the mineral-enriched waters.
As soon as they've mastered their trunks, they're hooked.
It may be that these mineral salts are also vital for the elephants' growth and fertility,
which is why as many as three thousand elephants visit Dzanga each year.
They'll try any tactic to control the best areas of the Bai.
Dzanga Bai is not the only clearing where they can get these salts,
but it's certainly one of the biggest and most frequented.
When Andrea Turkalo first came here, she had an instinct that this place
could help her unlock the secret lives of forest elephants.
I knew immediately that this was an extraordinary place, because to
see wildlife in the open in the forest is literally impossible.
I went there first in 1987 just to see the place and actually slept there.
And all night there were these extraordinary elephant sounds
because elephants don't sleep like we do.
There was just this symphony of elephants.
And in the morning they were still there and it was obvious that this
was probably one of the most special places for them in the Congo Basin.
Andrea now understands what the symphony means.
She can even hear an individual elephant's voice.
But back then, she was faced with a huge problem.
Each elephant visits for just a few hours - at best, a few days - so Andrea only had snapshots to go on.
She might not see them again for months or years.
From this constantly changing cast of characters, how could Andrea work out the big picture?
There was another challenge.
Andrea wasn't a trained scientist,
but she had been a teacher in the Bronx, one of New York's toughest neighbourhoods,
and she was single-minded enough to commit herself long term.
She left her family and friends and set herself up in the middle of nowhere.
At the beginning, I can honestly say there were a lot of things I was afraid of.
I wasn't really comfortable in the dark.
You're always in contact with insects and that was something I didn't like, but if you're
going to stay here, you have to get used to that and deal with it.
Andrea's had to turn her hand to everything, building a camp
from scratch and surviving on minimal creature comforts.
She's also had to place her trust in the local BaAka pygmies.
They come from an ancient tribe who have always lived in this forest.
They have helped her to adapt.
All my employees come from the local BaAka tribe.
They have great forest skills, they keep me out of harm's way
and they see things long before I am aware of them.
Every day, Andrea sets off with her loyal helpers on the 45-minute walk to the Bai.
It's a routine she's stuck to for 20 years.
Today, like any other day, she has no idea who, or what, she might see.
ANDREA: Oh my God, it's Gookie.
I can't believe she's come back.
I haven't seen her in about six months and she's still able to keep up with her group.
And she's still walking.
It's not uncommon for calves to be born with disabilities.
What's unusual is that Gookie has survived for so long.
Unlike on the savannah, there are no large predators here, which might explain why.
But life in the forest for a disabled calf is by no means easy.
What really amazes me about this individual is, if you think about walking in the forest,
the mother must come to obstacles like fallen trees,
so she's evidently accommodating the female with the handicap
because she's keeping up with the group.
Otherwise she would just get lost in the forest, left.
This place never ceases to amaze me... the things you see.
Even though Andrea sees individuals only rarely, she's been able to piece together their life stories.
She couldn't have reached this extraordinary position
without first learning how to pick out faces from the crowd.
By mid-afternoon, the crowd can be 140 strong.
To keep track of so many individuals, Andrea drew pictures of their ears,
which get ripped and torn in distinctive ways as they move through the jungle.
She had over 4,000 identity cards
before she realised her phenomenal memory was taking over.
I think the big breakthrough was when you realised you knew the elephants, you felt empowered.
You could just go out there and look and you knew them,
like you would see someone on the street in your hometown and recognise them.
Now, her encyclopaedic mind holds details of countless unfolding family sagas.
During the hours she spends at the Bai, she notes all the arrivals, and crucially, who greets whom.
It's late afternoon, and Andrea has noticed
two related elephants who've arrived from different parts of the forest.
ANDREA: This is Mimi One, who's the matriarch of this group.
Mimi One knows that Mimi Two is there.
Yeah, they're heading right towards each other.
Here we go, there's a nice greeting going on right now.
Some very low frequency, yeah, now they're trunking each other.
Yeah, yep, that's a mother and daughter.
So some of these greetings are very subtle and if you know the
individuals then you can predict them.
By understanding these relationships, Andrea's made an important discovery.
In the forest beyond the Bai, it's rare to see more than one elephant at a time.
People assumed they lead solitary, independent lives.
Andrea believes that, even though relatives might not stay together in
the forest, they do appear to know each other's whereabouts.
I think there was a general misconception about forest elephants only having small family groups.
But they do have extensive networks and they should because,
we know that about savannah elephants,
why shouldn't forest elephants still maintain these social groups?
Dzanga Bai, as well as offering medicinal salts,
appears to be an important venue for elephant family reunions.
Andrea is beginning to understand why the BaAka call this place 'The Village of Elephants'.
But even the BaAka don't understand how the elephants appear to second guess each other's movements...
how they know when other family members will be at the Bai.
To get to the bottom of this,
Andrea has had to start thinking like an elephant...
..tuning in to this forest world as they do.
A heavy storm prevents Andrea being at the Bai,
but even from her office, she can hear the elephants calling.
For two decades, she's spent more time with elephants than with her friends and family.
But even so, she's only witnessed a fraction of what they do.
Forest elephants spend only 5% of their lives at the Bai -
mostly at night when Andrea's not there.
THUNDER
It's at night, when they're visible only by starlight,
that the elephants are at their most sociable...
and most vocal.
It's also when Andrea is most worried for them.
Huge reunions out in the open place forest elephants in grave danger.
Every year, one in ten of Dzanga's elephants is taken by poachers.
Andrea's no longer here just to study them...
she feels a growing duty to protect them.
She believes their conversations are rich in meaning,
and that one way to help is to listen to what they're saying.
Today, she's adding to her vocabulary.
And to get a better view of the clearing, she's working from a viewing platform.
We're up pretty high, I think we're up about maybe seven metres
and you can see one end of the Bai from the other.
And you see all the entrances to the Bai, so I'm able to keep track of all the individuals that come in.
From up here, she can compile a kind of elephant phrase book
which links particular behaviour to the calls they make.
What I'm doing is I'm trying to capture vocal sequences between elephants in the clearing
in order to build up an elephant lexicon,
what these vocalisations mean.
Because I know the individuals, I can also anticipate these vocal events.
Someone's lost.
It's probably a juvenile lost its family.
An elephant's hearing is phenomenal.
They can hear much deeper sounds than we can.
Technology is helping Andrea to record these very low frequency calls
that are normally inaudible to humans.
Yeah, Milo's checking out this female.
She's doing a very nice rumble.
Elephants often do that while the female's being checked out by a male, they do this real low rumble.
Andrea can now identify ten different types of call.
She's even discovered that each family has a distinctive voice.
BABY ELEPHANT CRIES
Oh, separated from its mother.
Oh, the mother is coming, here comes the mother -
the mother hears the baby crying.
Here she is, she's vocalising.
There's a lot of low frequency going on now, reassuring the calf.
And probably the calf is learning the family's
specific calls.
Back in camp, Andrea can analyse the recordings and start to see the pattern of each elephant call.
This is a clip that I've pulled off.
It's to illustrate the distress call in a young calf.
And it's crying,
and it makes this sort of very low, mournful sound and what you'll see
next in the tape is the response of two young sub-adult females.
They approach the calf and then they discover each other and this
looks like a small greeting, but then they go back and follow
the calf, who's probably heard from its mother in the meantime and is approaching its mother.
Each sound recording gets turned into a spectrogram, giving Andrea a detailed picture of the call.
This is the calf's call and then you have these very low
frequency calls here.
I mean, you definitely see the calf calling, you see the mouth open,
but to know who's making those low frequency calls is difficult.
But, because the calf turned around and went in the other direction, I would assume it's the mother
and it recognised its mother's voice and now it's approaching its mother.
If you collected enough of these distress calls of calves of a certain age,
you could compare them to see if this is your typical distress call.
Andrea has developed an amazing skill.
By learning their language, she can interpret what they're doing.
This is a greeting between three members of the same family.
They're all vocalising.
They've all recognised each other and they've all grouped together and you see their ears are flapping
and they're trunking each other and they're very excited to be together again.
So I assume that they were separated for a bit of time because of
the energy involved in their vocalisations.
Their rumbles can travel over a mile through dense vegetation.
Even though family members are spread out, they can hear an invitation to meet up.
Part of the call is inaudible to our ears, it's infrasonic,
but a lot of it is audible and that's what we're hearing.
But these low frequencies are the ones that travel the farthest through the forest.
If they're having this greeting and there are individuals related to
them in the nearby forest, they're going to hear it.
And a lot of times you see other members of their family show up.
If their social networking is this powerful, they might even be able to warn each other of danger.
The following morning, the Bai is eerily quiet.
THEY CONVERSE IN LOCAL DIALECT
He's saying that
he's found blood on the trail and there's a lot of elephant tracks.
Days like this remind Andrea how vulnerable these elephants are.
I can see blood right here.
He ran here but we can see tracks all around here... there's more here...
more here...
So you can actually see where the elephant has trampled the earth.
He's probably panicking.
And he looks pretty big... SPEAKS LOCAL DIALECT
You can see a track right here.
Pretty big male, that's the track of the front leg.
Most forest elephants have tusks.
The biggest adults carry the most ivory.
OK, This is a big patch of coagulated blood, it's pretty fresh so it's from this night.
And there's also a track... Now they're saying it might be a female.
Where we are now is only about probably 30 metres from the Bai.
But we suspect the elephant was probably shot on the other side and ran because we didn't hear any
gunshot in the night and, generally, somebody will hear a gun if it goes off.
Dzanga Bai is within a National Park, so all Andrea can do is report the incident to forest guards.
It's a hard place to police, but Andrea's very presence in the
area does make events like this less frequent than they'd otherwise be.
Andrea wants local people to understand the value of elephants,
not just as intelligent, interesting animals,
but because, in their secret wanderings,
elephants influence the shape and richness of the forest itself.
The richer they make the forest, the more food there is for everyone.
The most obvious way they do this is by engineering pathways through the tangle of vegetation.
Over time, elephant feet have created wide trails, highways that run for
hundreds of miles through the forest, and which link key resources.
We're walking along a pretty well-worn elephant track and occasionally
the areas open up like this because of the existence of this tree.
This is a particularly favoured tree of elephants, it's Duboskia.
And generally the forest opens up here because elephants come here and they eat the fruits.
It's a very fibrous fruit and we find it
in about 90% of the elephant dung throughout the year.
So there's always a Duboskia tree fruiting
but they also tend to scrape the bark off and eat that.
Their trails are used by many other animals.
Western Lowland gorillas eat the same kinds of fruit as elephants,
so elephant paths are like signposts to food.
But there's one type of fruit that only the elephants can get to.
Omphalocarpum fruits are encased in a tough shell, making them virtually impossible to crack.
Elephants have the perfect tool for the job.
They may devour everything, but the seeds of all the fruits they eat pass unharmed through the gut.
As they travel, the elephants replant the seeds, creating avenues of their favourite fruit trees.
Where there's a lot of elephant activity, areas open up and sedges and grasses can take hold.
They are fundamental to the gorillas' diet.
These great apes would find life much harder without the elephants.
But the relationship isn't an amicable one.
Elephants don't like other animals sharing the clearings they created.
As they dig for minerals, they actually maintain and expand these Bais.
Over centuries, elephants have made hundreds of small
clearings in the forest, but none compares to the importance of Dzanga.
It's now the dry season, one of the busiest.
And for Andrea one of the most fascinating times at the Bai.
It's when most of the big bulls show up.
This is Triple Bite.
Over the years, Andrea has watched him grow from an adolescent
into one of the most dominant bulls in the clearing.
But he hasn't been here for nearly a year.
He has travelled hundreds of miles to reach Dzanga, where he knows he can find females.
It's not just the females that sense the tension rippling across the Bai when the big males arrive.
That's Gonya Five chasing Sitatunga.
For the younger bulls especially, this can be a very exciting time.
The young elephants they come and they're very feisty
and they'll just run around in the Bai for the entire afternoon.
He's like a young male in puberty so he's learning how to be a man.
Unlike on the savannah, elephants rarely see each other in the forest.
This clearing offers rare moments of contact, time for the bulls to get to know each other
and learn each other's strengths.
And everything they do is copied by the youngsters.
A lot of learning going on here,
sort of like a schoolyard.
Elephants are so much like humans.
We learn to be human, we end up being socialised, and elephants undergo the same process.
Andrea calls this "Bull School",
a time and place to learn their position in elephant society.
When I started this study I had no idea about how conscious they were
and yes, they do have good memories and they have personalities.
And watching an elephant grow from childhood to adulthood has been astonishing to see the changes
and how much they really have to learn to become an elephant.
Andrea has revealed something even more significant about Dzanga Bai.
This clearing is the place where elephant culture is passed on.
Understanding the central importance of Dzanga Bai places an even bigger burden on Andrea's shoulders.
Her presence here is not just preventing elephant deaths,
but the possible disruption of their entire way of life.
She wants to protect the elephants, but she has to work
within a culture that has very different attitudes and priorities to her own.
For centuries the local BaAka
have hunted forest wildlife for food and Andrea is pragmatic about that.
Traditionally, the forest for them has been
their life source, where they find everything they need.
You know, they eat elephant meat. That's not a mystery to me.
Andrea steers a difficult course between her feelings
for the elephants and respect for the BaAka's traditions and needs.
A lot of them will go into the forest for two or three months
of the year where they'll gather honey and certain seeds that they eat.
I've made their work schedule very flexible because if they want to go
into the forest they can tell me, and I'll say fine.
That's a very important part of their culture,
and they need to teach that to their children because ultimately it may be the only way they'll survive.
Not many employers would be this flexible, but she believes it's the only way.
You have to be there for them when they really need you
because otherwise they won't be there for you when you need them.
And I think that's really sustained me here in many ways, that connectedness to people here.
Andrea treats her BaAka workers like family,
making regular trips to buy them supplies.
The local village is only eight miles from Andrea's camp,
but the round trip on rough, dirt tracks takes a whole day.
It's impossible to grow anything in camp because elephants raid the crops at night.
The heat and humidity means that nothing stays fresh for long.
This is smoked fish and if you buy it smoked you can keep it up to two weeks in camp without refrigeration.
I don't eat smoked fish.
I mean it's an acquired taste.
Protein is difficult to come by.
What there is tends to come from the forest.
Local people are allowed to hunt outside the national park,
but laws control which animals can be taken as bush meat, and how many.
Even so, Andrea knows there's elephant meat under the counter.
The guards that patrol the forest do their best to contain this black market.
More commonly, they pick up people who have taken too many animals
or who have the wrong licences for their weapons.
Most people are just trying to feed their families.
Elephant meat is a delicacy, but it's rarely on the menu.
They are hard to kill with a normal shotgun.
And Andrea's work is making a difference.
When I first started working with the BaAka, I think we all had this vision that they know the wildlife.
But they didn't know elephants in the way that they've gotten to know them with me.
But because now they've spent many years observing elephants first hand their ideas have totally changed.
In fact one of them said to me one day, "Madame, these aren't elephants, these are people,"
and it was very touching to me to hear that.
Sadly, local opinions are increasingly affected by bigger changes sweeping across the region.
Andrea's seeing more and more elephants entering the Bai.
She thinks they're being pushed into Dzanga,
as commercial logging disrupts their extensive network of paths.
What's more, ivory is back in demand.
And the tusks of forest elephants are most sought after.
They are pinker and much denser than those of savannah elephants, resulting in a "rose ivory"
that's highly prized for carving.
Its value is astronomical.
A pair of tusks raises 90,000 on the black market.
It's no wonder some local people get drawn into poaching.
Human conflict in neighbouring countries floods the area with weapons.
The guards confiscate many of them, but there are plenty more and they're largely pointing at Dzanga.
It's the easiest place to find and kill forest elephants, unless, of course, Andrea is there.
I will react immediately to any threat.
I can be out at the clearing having a nice afternoon and then I hear gunshot and I'm gone,
I'm back to camp, on the radio trying to get guards motivated.
In many ways, Andrea is the only person standing between the elephants and mass slaughter.
After years of wanting to be here, she now dare not leave.
Even trips to the local town could endanger the elephants, because she's under surveillance too.
Her absence from the Bai never seems to go unnoticed.
The poachers are very localised, I mean, they live in the village, I know them, they know me.
So when I'm driving out of town they see me.
People are going "Andrea" by the side of the road,
so they know I'm leaving and that's a worry because there
have been incidences where there is poaching when I've been gone.
This video was taken when I wasn't at the Bai.
It was taken by one of the assistants and he told me about this bull.
This is an elephant Andrea knows well.
But he now has a line of wounds across his flank.
He's a young bull, he's about 35 to 40, his name is Hezy.
The wounds are definitely bothering him. You see this often in elephants when they've been wounded.
They'll spend a lot of time either
throwing water on themselves or mud.
Cos those wounds are pretty deep, I mean they
pierce the epidermis, which is about half an inch thick.
Andrea can tell from the pattern of wounds this was not the result of a fight.
That many wounds, I'd say a Kalashnikov.
Hezy has returned to the likely scene of the crime,
perhaps because it's also the best place to treat his wounds.
But since this video was taken on May 13th we haven't seen him,
so, he might have even died, might have developed an infection from the wounds he sustained.
With the stakes becoming higher, even Andrea cannot live in such remote forest without protection.
She needs to share the weight of responsibility,
and a chance has come.
She's been asked to help with a pioneering study at the other end of the elephants' range.
It means, for a few weeks, she will have to leave the elephants at Dzanga Bai.
Forest elephants inhabit a huge area stretching over two million square miles.
But there could be fewer than 125,000 left.
This is Gabon...
..where the African rain forest meets the ocean.
It's considered to be one of the last safe havens for forest elephants.
It couldn't look more different from Dzanga.
Beyond the endless beaches there's a mosaic of savannah, forest and swamp.
It's a new experience for Andrea.
She's used to seeing groups of over 100 elephants together.
Here, just seeing one is a challenge.
You don't see many, but when you do see them they're doing extraordinary
things that I've never seen before in my life.
Elephants have adapted to this diverse range of habitats,
even snorkelling across flooded channels and swamps.
This place gives me a lot of hope in terms of
elephant conservation, just because the elephants aren't accessible.
People can't hunt in these swamps and so that is a refuge for them.
However, there's no clearing like Dzanga to see elephants and monitor what they do.
Researchers have had to find a different way to tune into their lives.
Andrea's joined Peter Wrege, from the Elephant Listening Project at Cornell University.
He's an expert in acoustic research, something he hopes will reveal more about forest elephants.
So, this is the hard drive to store the data and then this is
the computer, microcomputer, that's actually processing the sound.
He's putting up remote listening devices to eavesdrop on them.
But he needs Andrea's help because only she can translate their calls.
We're still in kindergarten in learning exactly what their vocalisations mean and the social
context in which they occur, and this is where Andrea is so vital to what we're doing
now, is that she knows the behaviour of the elephants very, very well.
These recording units contain state of the art microphones,
specially designed to pick up low frequency calls.
They can be left running for three months, 24 hours a day.
Each one records rumbles from over a square mile of jungle.
It's better than CCTV. That's OK.
So, we're finished, ready to go. It's absolutely a kind of spying on elephants, listening in
on their conversations in order to understand what they're doing, how many there are, where they're going.
Peter already has 33 of these bugging devices deployed in the rain forests of Central Africa.
Now, he needs Andrea's help to decode the latest recordings.
ELEPHANTS RUMBLE
It's pretty deep. Hmm. The different rumbles tell
Andrea how many elephants are present and what they're doing.
OK, that for me, this first call
may be an adult female
and this might be a response to that call.
Let's try this one then.
This is a young animal again. Young animal.
Just by listening, she can tell which members of the family may be vocalising and why.
Would you call those all protest calls, or you said also sometimes they just get separated...
No, I think they're lost calls, I think they're separated.
So you can, you're actually hearing a difference between a protest and a lost?
Yes, those sound like to me lost calls.
It starts low and it goes up. The structure looks
the same. Yeah, well that's one of the problems.
I need to know more from your ear what do I need to be looking for to make that distinction.
Andrea's knowledge will help Peter create a visual record of specific elephant calls.
He can then refer to this library and learn even more about elephant life here.
You don't have anything before that, do you, recorded?
Oh, I'm sure I do.
This is clipped out.
It almost sounds like mating. Really?
Yeah, because you've got a lot of these high pitched things going in.
Without even seeing elephants, it's possible to translate
their rumbles into information about breeding success.
They've also revealed the dangers elephants face.
Before his study began, Peter was told there was no poaching in the area.
That's not the case.
These, I'm pretty sure are high powered rifle shots.
So, these devices also spy on the poachers.
By pinpointing hotspots of illegal hunting, guards could target areas more strategically and efficiently.
Lot of frogs.
Yeah, those are definitely guns.
And again, this is a bit strange because the intensity changes.
CRACKING SOUND ON TAPE
That's a tree. Really?
That's a tree. This first thing right here, this
first sound you hear, it's the crack and then it's the ki ki ki ki.
I don't know, Andrea.
No, I'd put money on that one.
CRACKING SOUND
Hear that?
CRACKING SOUND CONTINUES
And that's the whole thing going down.
It might get hung up on something.
True, a lot of trees out there.
Yeah, it's very complicated, tree fall.
20 years in the forest has taught Andrea what to listen out for.
And Peter knows the value of her extensive memory bank.
I'm very concerned actually about
the huge knowledge that Andrea has about these elephants.
I find it phenomenal what she remembers.
No-one else comes anywhere close to what she has, so I think it is critical that we basically
kind of extract this information from her brain.
This experience has shown Andrea how her knowledge could help elephants across their whole range.
But she will always feel a strong connection to the individuals
back at Dzanga that have been her life for so long.
I probably think about these elephants during my waking hours about 90% of the time.
I'm very concerned about them. I mean I feel it's my moral responsibility to be there.
Hopefully when I get back, you know, the numbers will be the numbers I'm expecting to see.
When Andrea returns to Dzanga there's depressing news.
More poaching has been reported in the area.
The demand for ivory is now threatening the very existence of forest elephants.
Recent data has shown we've maybe lost between
40 and 50% of the population in the Central Africa area.
So there's increasing pressure on this area where there are still animals left over.
Dzanga Bai continues to be a magnet for forest elephants,
and a privileged window into their lives.
That's Marnie.
Oh, there's a new calf.
For the next 60 years, this calf could return time after time to take
the salts, meet up with family and to find a mate.
That's nice. That's a new baby for today.
He's trying to figure out what to do with his trunk.
But if Andrea were to leave, who knows what upheavals he and his family would face?
I'm not an optimist about the future for animals here.
So I mean, I get a little bit emotional about it,
but the reality is, these animals if they're not protected they're going to be poached.
For two decades, she has carried this responsibility on her shoulders.
But she cannot stay here for ever.
I've been here for 20 years and I'm beginning to feel my age.
I think I'll stay here as long as I can walk and I can get support to do what I do because I love this place.
There's a lot of downsides to my job, but coming here every day
is what makes it all worthwhile and just seeing them right here.
Maybe the pioneering study in Gabon will eventually take the pressure off her.
And the remote listening devices will become her ears in the forest,
allowing elephants to tell us of the dangers they face,
as they continue their conversations through the jungle.
Subtitles by Red Bee Media Ltd
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