Natural World (1983) s28e11 Episode Script

You can see them from space - a mysterious network of pathways carved in the Kalahari sand.
They are the imprint of a hundred generations of elephants who've walked unhindered across this landscape.
But the current generation of elephants in Botswana is walking into an extraordinary crisis.
Numbers here are growing rapidly, and some experts believe there are too many elephants.
To sort out the problem, they are proposing drastic action.
GUNSHO Dr Mike Chase is an independent ecologist who has dedicated the last eight years to studying elephants.
Working with leading conservation groups, governments and farmers, Mike is trying to avert the looming crisis.
The fate of as many as 60,000 elephants may depend on what his research reveals.
In June and July, the dry season takes hold of the land.
Thousands of elephants are forced towards the few sources of water that remain.
These are on their way to the Chobe River, on Botswana's northern border, where they will converge into the largest gathering of elephants on the continent.
Elsewhere in Africa, elephants are in decline, but in Botswana, largely due to far-sighted conservation efforts, elephants are doing well.
Too well, perhaps.
The population here is officially estimated at 150,000 and it's doubling every 15 years.
TRUMPETING Experts are worried that the elephants will soon destroy the fragile ecosystems on which they, and so much other wildlife, depend.
Some scientists look at gatherings like this and predict environmental catastrophe.
There have even been calls for a pre-emptive cull, literally shooting 60,000 elephants.
Mike Chase is horrified by this idea.
He's a native of this land.
He grew up in the bush, where his fascination for elephants began, and he's spent most of his life watching and studying these gentle giants.
Mike is concerned by the rise in elephant numbers, but he also thinks there's more to the problem than meets the eye.
He suspects that numbers here are artificially high, that many of these elephants are refugees from surrounding countries, an accurate assessment of the elephant problem, based on this temporary gathering at the Chobe River.
During the dry season we can see thousands of elephants coming to quench their thirst along this river, but in the wet season they disappear.
You can come here and for days on end not see an elephant.
Elephants are arguably the most well-studied animals on the African continent, but we know so little about their movements.
Their movements remain a mystery and here in Botswana, where we have the largest wilderness area left for elephants to roam over, we knew so little.
Mike has made it his mission to investigate these uncharted elephant travels, and the question of elephant numbers before drastic decisions are made, and certainly before anyone considers shooting elephants.
To start filling in these critical information gaps, Mike first needs to find out where elephants go once they leave places like the Chobe, and how they use the food and water resources during the rest of the year.
Only then will it be possible to know whether there are too many elephants in Botswana.
Botswana is a vast landlocked country the size of Franc .
.
and more than 80% of the land is covered by the Kalahari.
Mike's initial aerial survey of the known elephant range, which extends thousands of square miles to the south of the Chobe, gives him a picture of the sheer scale and diversity of their surroundings.
But as Mike flies back and forth across the Kalahari, he becomes aware of something extraordinary.
One of the amazing things I noticed from the air were these incredible highways, this extensive network of ancient elephant pathways, that link all the waterholes like a string of pearls across the desert.
If I could discover how elephants move along this huge web of pathways, perhaps I'd be able to understand their survival strategy.
How do they find the scarce and widespread resources of the Kalahari? The only way Mike can unlock these secrets is by fitting radio tracking collars to as many elephants as he can.
These collars will do the long-distance detective work, storing precise information about the elephants' movements.
I started by collaring several young elephant bulls.
We know from studies elsewhere that they range much further than females, and I hoped they would provide the most interesting and dramatic movement results.
We found this young male at the extreme edge of the elephant range, about as far from the Chobe as elephants can get.
For me, it's always an incredible experience to work up close with these gentle giants.
I'm never really comfortable having to immobilise an elephant, but I remind myself that these few individuals will ultimately be helping tens of thousands of other elephants.
I hoped that this young bull might provide priceless information.
I decided to call him Max.
Mike hopes that the daily GPS co-ordinates stored in Max's unit, and those of the other elephants he's collared, will tell him how elephants navigate around this complex network of pathways.
What he has to do is locate Max every three months or so, then he can download the data.
Until then, Mike spends time staking out a few well-known elephant drinking places.
I've spent a lot of time studying bulls at their regular waterholes, but in the months that followed, I was surprised I didn't see Max at any of these usual places.
I began to get the feeling that he might be a real wanderer.
Once teenage males leave their maternal herds, they join up with other bulls, constantly exploring, and learning where to find food and water.
For a few years they will journey with the bachelor herds, but soon the more adventurous of the young bulls break away, to follow their own path.
The question for Mike is - how are they able to make the most of these scattered resources in order to survive? He hopes that Max will provide the answers.
Nearly four months after he was collared, Mike attempts to find Max from the air.
He can detect Max's collar from about 20 miles away, but that's a tiny range in this immense landscape.
Time is critical, because soon the data stored in the collar will begin to overwrite itself.
There's a great urgency to find Max and download this location data that is embedded and stored in his collar to better understand how these young bulls are moving across this landscape.
We haven't been able to find him now for at least three to four months.
Either his collar has failed, he's wondered into an area that is very remote or you know, I It's just horrible not knowing where he is, and every time I land without having found or picked up a signal from him, I just feel really disheartened and upset.
Mike may have more luck with the females he has collared.
Family groups make up over 90% of the growing elephant population, so if there is any impact on this fragile desert environment, it's likely to be caused by them.
This is Bontle, the leader of a typical Botswana family group.
She's one of the females carrying a newer type of tracking collar, which records a GPS waypoint every two hours.
Not only will it tell Mike in much more detail where she goes, but it's a collar that also makes her easier to find.
Now Mike can follow these elephants after they leave the Chobe River and witness first hand their journey into the desert interior.
As the summer rains begin, they start heading south, and the pressure of elephant numbers is lifted from seasonal rivers like the Chobe.
Heading out along hundreds of different pathways, Bontle and the other family groups fan out into the immensity of the Kalahari.
Summer thunderstorms here are incredibly localised, bringing small areas of the desert to life.
Rain may collect in one shallow pan, while leaving others nearby completely dry.
Some of these precious waterholes may be over 30 miles apart.
Female elephants cannot go for more than three days without drinking.
In the relentless heat, they have to keep journeying to survive.
Whenever he can, Mike tracks Bontle and the other collared females, following their long journey into the elephant heartland.
It's up to the matriarchs, like Bontle, to lead their families to distant, scattered sources of food and water.
Even in the so-called wet season, the Kalahari remains harsh and unforgiving.
The desert pans are dotted far and wide across the landscape, linked by the web of elephant highways.
Time and time again, Mike witnesses their remarkable ability, as matriarchs choose a route which bypasses empty waterholes but which leads, unfailingly, to full ones.
INAUDIBLE Every small pool is a lifeline.
Look how they are running in This little elephant is only a few hours old.
His mother would have given birth in the middle of the desert, so he may already have walked many miles to reach here.
It's the first water he's ever seen.
The stop at this pool will give him the day or two he needs to find his feet.
He's already socialising with members of other herds, and even the great old bulls who come here.
Mike believes that the little calf won't forget this experience, that the memory of this waterhole is now embedded in the youngster's mind.
But once this water's gone, the tiny calf has no option but to follow his family for many miles to the next pan.
The Kalahari is about as hostile as it gets for an elephant.
But if there's one thing I've learned from years of watching elephants, it's how incredibly intelligent, resourceful and adaptable they are.
I'm convinced that elephants remember key pathways and places, and continue to create a mental map over a lifetime.
A calf is at the beginning of this process.
Every day it adds to its mental map, as it follows the elders around.
Older, wiser members of the herd are effectively passing on a detailed body of knowledge - the pathways to food and water, and the timing through the seasons, which have allowed that particular family to survive here over many generations.
The collars are giving Mike a greater insight into elephant behaviour, and in some cases leading him to new discoveries.
A GPS message takes him to a place he's never been to before - a waterhole right in the middle of the Kalahari.
Dozens of major elephant highways seem to converge here from every direction.
It's so extraordinary.
I've never seen so many elephants around a small little pan.
I mean, all around us here and there, more elephants.
About 200 to our right.
We're just surrounded by them.
In the middle of this extraordinary gathering of 5,000 elephants is the one who's inadvertently led him there.
Kel, I can see Bontle! Right there, right there! Hey, big girl! She's got a calf, she's got a calf, she's got a calf! Man! That's so cool.
And we would never had found this place had it not been for her.
I mean, here at Chinamba, right in the middle of the elephant heartland.
She must have journeyed hundreds of kilometres to get here.
Hey brilliant, man.
Bontle and all the other matriarchs have ignored good waterholes nearby.
What's drawn so many families to this particular pan? This has to be more than just a coincidence.
I began to realise that there must be a deliberate intention to this congregation.
That not only do they all know how to get here, but also the timing of the others' arrival.
It seems that they're thinking beyond their own family experience, and suggests an elephant intellect far more complex than we might have imagined.
Mike believes that they may be directly communicating and sharing information, or networking in some way, that may have long-term survival benefits.
He thinks this kind of clan group might be an important event in an elephant's life.
When bonds are reinforced between family groups, vital decisions are made and survival strategies are shared.
Bontle is part of this concentration, and Mike hopes the information being stored in her collar might some day help to explain this remarkable gathering.
But there are very few bulls here.
Where are they while the female clan groups are assembling? If he can find the elusive Max, Mike might be able to answer that question.
He has searched the elephant heartland for Max, and exhausted all ideas.
Now he needs fresh inspiration.
There is ancient wisdom in this land, a wisdom born of a harsh and primeval environment.
The San Bushman people have walked the Kalahari for a very long time, long before anyone ever drew lines on a map.
Their intimate knowledge of the land and the animals has been critical to their survival.
This knowledge is passed down the generations by the shamans and great storytellers.
Perhaps their wisdom could add valuable information to Mike's research, and maybe even help him find Max.
Mike decided to visit one of these traditional storytellers.
A family friend he's known since he was a boy.
I met with Xguka at the most sacred site in San Bushman culture, the Tsodilo Hills, that rise out of the western desert, beyond the known elephant range.
She led me to extraordinary rock paintings of elephants that lived here thousands of years ago.
Xguka knows that elephants still remember these remote places and how to survive here.
She assured me that, like the San Bushman storytellers, elephants have handed down their knowledge through the generations.
Xguka talked late into the night, telling me stories of how elephants travel far and wide, and how they make ancient pilgrimages to visit the lands of their ancestors.
And she encouraged me to venture much further in my search for Max.
The bushmen have their own explanation for extraordinary elephant movements.
And Mike is eager to put his scientific thinking aside for a while, and journey into the unknown.
Following Xguka's advice, Mike explores the Makgadikgadi salt pans, an immense and hostile desert, far south of the current elephant range.
It's somewhere he's never really thought of looking for elephants.
And yet he finds clear signs of elephant bulls, trekking across this vast infinity of salt.
These tracks are not necessarily Max, but they are undeniable proof that bull elephants use this area on their wanderings.
As Mike expands his thinking, he also expands his search.
Eventually he gets his breakthrough.
There's a faint signal.
There he is! Yeah, that's definitely a signal! Woo-hoo, we found Max! That's excellent.
Super, man! What we'll do is just drop in altitude and then download all this wonderful information.
I've established a link with the collar, so it's downloading data now.
Great, almost done.
DOUBLE BLEEP And that's it, we have it.
100% data acquisition.
Super.
Thanks, guys.
Max's results are staggering.
He has covered an astounding 13,500 square mile area, the largest home range ever recorded for an African elephant.
Max is also moving beyond Botswana, crossing international boundaries, travelling a network of pathways from the rich woodlands of the north, to the barren extremes of the southern salt pans.
At last, after years of guesswork, elephants are showing Mike exactly which routes they use from season to season.
This was a direct communication between him and the elephants.
Mike wants to know where Max is finding food and water on these driest fringes of the Kalahari.
Retracing Max's journey, he begins to search for clues.
There's some information satellite collars and satellite images can't give me, and I have to physically come out here and try and determine what's attracting elephants to these harsh and arid environments.
There's a lot of elephant activity, clear signs and tracks of them moving across these little salt pans.
Oh, my goodness.
Right here, in the middle of this pan This is how they're managing to survive, by digging for water.
There's no surface water so they've had to dig for it.
You can certainly drink it, it's not salty at all.
It's a discovery that encourages Mike to look for other elephant activity, using some of the GPS points gathered from Max's wanderings.
Most don't reveal anything significant, but one place Max has visited turns out to be very special indeed.
I've been lucky to find a small water hole, and so this is going to greatly improve my chances of seeing the elephants, because I hope they come down and drink here.
So I'm going to sit here and try and hide in this grass, and hopefully see some elephants this evening coming down to drink.
This bull is probably 50 years old, with a full lifetime's knowledge of the Kalahari.
That knowledge is critical to the survival of elephants here.
It is wise old bulls like this that would have taught Max.
If bulls are showing Mike just how far elephants can travel, what will Bontle's collar reveal? It is time to take her collar off and find out.
The batteries in Bontle's collar are about to fail, so it's done its job.
Go well, big girl.
But it's also important to Mike that collars are removed once they're no longer necessary.
You are free to go now.
Thank you.
Thanks, Larry.
Now Mike must send the unit away for the data to be extracted and to find out exactly where she's been.
This is a beautiful winter morning out in the bush.
And it's a particularly exciting morning because I've just received the information.
So the moment of truth has arrived.
Bring it into my mapping programme.
Oh, my goodness! Right where I'm sitting, she's been here.
And you can see the paths she's actually using to migrate down here.
Ten GPS coordinates a day - almost one every two hours.
It's just fantastic.
And a home range size - 13,848 square kilometres.
For Mike, this is a revelation.
The average home-range size for an African elephant cow is 2,000 square miles.
Yet Bontle had covered nearly five times that area.
Like Max, Bontle's family needs to travel huge distances to survive in a place where food and water are so widely scattered.
It's a clear indication of just how much wilderness these elephants actually need.
But there is also something disturbing about her movement patterns.
A clustering of waypoints up by the border shows that Bontle was repeatedly back-tracking across a small area, instead of venturing onward along the web of pathways.
It suggests her movement is being blocked.
This one of the region's veterinary cattle fences, put up years ago to prevent the spread of foot and mouth disease.
In the north-west of the country, some of these fences run for hundreds of miles across some pristine elephant habitat.
A fence like this is probably not a serious impediment to an elephant bull.
But when we are talking about matriarchs with their calves, the old cows can probably step over the fence, but their calves certainly can't negotiate these fences.
The matriarchs on their long migrations are stopped literally in their tracks.
These are Bontle's movements, combined with those of other females Mike has collared.
When a map of the fences is overlaid, one of the problems becomes clear.
Some of Botswana's elephants are trapped.
But there is another abnormal clustering of waypoints to the north-east of the fence, that Mike cannot easily explain.
In this area, there are no fences, but what Mike finds there is just as dramatic and discouraging.
Before sunrise every day, I watched thousands of elephants, mostly matriarchs and their families, running across these barren plains.
Clearly they were highly stressed.
These floodplains are an international boundary.
And just beyond that there are many small farms, close enough for me to hear shouts and gunshots, as farmers drove the elephants back across the border to Botswana.
Why were these elephants running back and forth night after night? Were they trying to raid crops? But why would they put themselves through so much stress? Mike realises then that Bontle and Max and the vast network of elephant pathways he's seen from the air, are giving him the answers.
Desperate to follow an ancient migration path to distant food and water, these elephants are simply trying to get beyond the farms using an age-old route deeply ingrained in their memory, which is now blocked by expanding human settlement.
This barrier is every bit as threatening to their survival as the fences.
There are always consequences for elephants in such an unnatural situation.
Their daily trek across and back is taking its toll.
The females are stressed.
Those with calves have little milk.
And it is completely exhausting for young calves.
Once the little ones stop moving, their fate is sealed.
Some are just too weak to go on.
I very rarely intervene.
But on this occasion the crisis had clearly been caused by man.
If I could just get this little elephant moving again, get him to catch up with his mum, who stood nervously waiting for him, perhaps he could make it to the shade and security of the Botswana side.
Incidents like this are a stark reminder that the future of elephants is in our hands.
Every year, human development blocks more migration routes.
Botswana's elephants are now surrounded by fences and people.
Elephants that came to Botswana looking for sanctuary are now stuck here, breeding fast, and with nowhere to go.
There may not be an elephant problem now, but if they remain trapped, then soon there will be a crisis.
Mike's findings don't just explain the problem, but also offer a solution.
He believes that we can relieve the pressure of numbers, not by culling, but by giving elephants safe passage out of Botswana.
Clearly it is too late to move people, but where Mike has identified clear migration routes, it may be possible to create elephant corridors, or gaps in the fences through which they can move.
The placing of these gaps is very intuitive - you put them where their migration paths are, smack in the middle.
We've got to be practical here.
We don't have to decommission hundreds of kilometres of fencing, we just need to give them a corridor, to allow elephants to be released, we can release this bottleneck.
Allowing them out of Botswana solves only one part of the problem.
The question is - where could they safely go from here? Botswana's vast wilderness is largely surrounded by countries that are developing rapidly, filling up with villages and farms.
But there is still one place that remains a perfect home for elephants, and which could provide sanctuary that Botswana's besieged elephants need.
Angola, a country now at peace after a long civil war.
Back in 1975, before the civil war, Angola had the largest elephant population in Africa.
When Mike first flew over south-east Angola in 2001, at the end of the war, there were no elephants left in those extensive woodlands.
Tragically, as many as 100,000 of Angola's elephants had been shot - for their ivory to help fund the war, or for their meat to feed their troops.
Most of the elephants that weren't killed fled to the safety of Botswana.
But the memory of the Angolan wilderness lives on in the minds of the older elephant refugees.
There are signs that some of them are trying to return home.
The great irony is that 30 years of war has actually preserved the Angolan wilderness, simply because it has been too dangerous for people to move back.
Landmine fields like this are all over the place.
There are an estimated 10 million unexploded landmines in this magnificent wilderness.
I believe elephants can smell landmines, like rats and dogs that are used to help de-mine areas.
Elephants have a very powerful sense of smell.
So my hunch is, and early evidence suggests, that elephants can detect landmines.
The matriarchs that used to roam freely in this part of Angola inherently will remember it.
A lot of the pathways have lain dormant, and now the war has ended, there's a perfect opportunity for elephants to return back to south-east Angola, return home.
Home is where the heart is.
We need to safeguard these new migration corridors that elephants are using to return home to Angola, to help secure a future for elephants.
Mike knows that given half a chance, more and more elephants will try to get back there.
But it's crucial to protect their migration routes now, before rapid development in Angola blocks their route home.
The Chobe River runs along one of Botswana's international boundaries.
For the first time in decades, elephants from the Botswana side have begun to use the river as a crossing point again, heading for Angola.
If Mike can continue to work with regional governments then he can help protect these corridors and ensure the elephants' safe passage.
But to do that, Mike first needs to clearly identify where their old, cross-border migration routes go.
What better way to map these highways than by asking an old bull elephant, who might remember Angola, to lead the way? Mike needs to collar a bull as close to the international border as possible.
An elephant old enough to remember his ancestral homeland, and who will provide a GPS trail, as he journeys north into Angola.
Yo! Look at that! That's so impressive! I've never seen so many large bulls in one bachelor group.
We have to collar one in this group, the biggest bull, if we can find him.
Hey, Larry, that big bull! The one with the big tusks! This huge bull is exactly what Mike is looking for.
He's certain this old elephant would have lived in Angola, and will probably go back there.
He's really impressive.
Man! Super.
How's his breathing, Larry? Good? 'I really hoped this magnificent bull would become an ambassador 'and lead the way back to Angola.
' I think he's about 40 years old.
Yeah, he's in his prime.
Mike has collared more than 50 elephants in a massive trans-frontier area spanning five countries.
He's unlocking the secrets of how these majestic animals move across this complex landscape.
Let's call him Ntombo! The collaring of Ntombo is a new beginning.
Mike's future challenge is to ensure that elephants have the freedom of Africa, that they can still wander as they did hundreds of years ago, and, most importantly, that elephants and people can learn to live peacefully together.
I believe that elephants are a flagship species and if we can't save the African elephant, what hope is there for the rest of Africa's wildlife? The great bull Ntombo strode north into the wilderness of Angola, carrying his collar with him, following an ancient migration path.
And now I dream that where he leads, a thousand elephants will follow.