Natural World (1983) s30e11 Episode Script

Meet Brutus, the leader of the Kyambura Chimps.
His community is plagued by nightmare teenagers, naughty kids, squabbling adults and serious rivalry.
But that's pretty normal for chimps.
Brutus has a problem that's much more serious.
These chimps live in a deep and ancient forested gorge that cuts through the plains of Africa's Rift Valley.
The Kyambura gorge may be a lush oasis, but it's also their prison.
Brutus and the chimps are trapped.
As the pressures of isolation take hold, can they stick together or will they self destruct? The Kyambura chimps have been marooned in a five-mile gorge in a corner of South West Uganda for nearly 15 years.
Their narrow strip of forest used to continue along the river like a corridor, to a much larger forest.
But in recent times the human population here has exploded.
Crops now cover the land, and the trees have all but vanished.
For Brutus and his community living in the gorge, their link to the chimps in the other forest has been severed.
These chimps may as well be on a desert island.
But they've got to carry on and do their best to function as normal.
Easier said than done.
Here in the gorge there are just five breeding females, a couple of grannies and 11 kids.
They are led by a motley crew of males - one old man, a couple of scraggly teenagers and only two prime adults.
It's not up to the usual standard of a male chimp defence force.
As the alpha male, Brutus presides over the whole group.
He's the most powerful chimp in the gorge.
It's his job to keep control.
But how will he lead such a ragtag band in these reduced circumstances? The forested gorge is a reasonably safe place for the chimps.
The trees provide an escape from predators.
But Brutus and his team are about to leave their sanctuary and set off on a high-risk mission.
Just the males together climb out of the gorge and into the danger zone.
Savannah.
Predators stalk the open grasslands.
It's a habitat made for fast runners, not tree climbers like the chimps.
This might seem foolish, but something drives them on.
On high alert, they creep forward.
A nervous band of just three big males and two teenage boys.
It's not much of a war party.
For the youngsters with their pale faces, it's seriously scary.
But still they follow the leaders without question.
But Brutus and his crew aren't on a mission to escape the gorge.
They've been lured out by a more immediate temptation.
The most delicious, juicy, ripe figs.
Safe off the ground, the chimps can relax.
The figs are a rich source of calcium and vitamins, and a worthy reward for their bravery.
Male chimps never leave their families, so these boys will stay together until they die.
They might be a second-rate crew, but they are the core of the Kyambura chimps society.
They have to stick together, work together and be a good team.
After eating until they could burst, the boys indulge in a little grooming.
It's an important ritual that cements the bonds between them.
Brutus gets all the attention, as befits his role as the alpha male.
All the boys like an opportunity to suck up to the boss.
Apart from one.
Hatari is a little younger than Brutus.
At 21 he's approaching his prime and has his eye on Brutus's crown.
His craving for power is so strong Brutus will need to watch his back.
Hatari decides it's time to go, and swings down first.
It's a bold and defiant gesture Brutus should always be the first to move.
He ought to put Hatari in his place, but out in the savannah they need to concentrate on predators, not politics.
There could be a lion around.
Having a troublemaker in the ranks is the last thing Brutus needs in this claustrophobic situation.
Back in the gorge the mothers are safe.
They have young babies to mind and teach.
While there's no chance of escape, every breeding female is extremely precious - to lose even one would have drastic consequences.
For now, they're all doing well and there has been a recent baby boom.
But a strange twist of fate will make the chimps' future in the gorge even harder.
None of the new babies are girls.
The community desperately needs more, but chimps are very slow breeders and on average each mother produces just one baby in five years.
Because four of the five mothers have babies under two years old, they won't be conceiving anytime soon.
That leaves only two females that could get pregnant in the near future.
One is Emiti, she has two boys already, one six, the other three.
If she can breed that fast again, and produce a girl, it will make a massive difference to the survival of the group.
There's a lot of hope resting on her shoulders.
But she's not carrying it alone.
Sharing her burden is Pamba.
Pamba is a teenager and her body is preparing to breed.
She too might get pregnant soon - another hope for a baby girl.
The only problem is that Pamba's hormones are driving her to leave the gorge.
Female chimps tend to leave their families when they become sexually active.
They do it to avoid inbreeding.
But if Pamba did stay, to have another breeding female around would be much better for the gorge community.
The deadly savannah stands between her and a new life.
But if only she knew how close the other chimps were.
Within seven miles of the Kyambura gorge there are two distinct forests, both containing healthy populations of chimps.
both could be walked to within a morning.
But the route to one is cut off by farmland and the route to the other by lion country.
Salvation is so near, yet so far.
The chimps can't know how close it is otherwise surely they'd run the gauntlet.
What they desperately need is for a new forest corridor to be planted, a corridor that would not only let Pamba out, it would also let other migrating females in, bringing with them much needed fresh blood.
But a corridor would have to be planted by people, and even if they were to start now, it will take at least 20 years for the trees to flourish.
The Kyambura chimps will have to stay strong if they are to survive that long.
So, despite her raging hormones, Pamba has nowhere to go, and applies herself instead to babysitting one of the toddlers.
It's a teenage female chimp's favourite pastime.
She uses a stick to fish for honey.
The toddler is fascinated.
More of a hindrance than a help.
He'll learn by watching.
It gives the mother a break and the experience is great for Pamba.
If she bears a healthy daughter in the gorge soon, it could be just enough to help the Kyambura chimps survive until rescue comes, if it ever does.
The boys have returned from their fig expedition, and once safely back in the gorge, Brutus, the leader, needs to reassert his authority.
SQUEALING, HOOTING At 26 years old, he's in his prime.
Strong, confident and in control.
His displays leave the others in no doubt as to who's in charge.
But Brutus can't keep control through violence alone.
Every alpha male chimp needs a side-kick.
Unfortunately for Brutus, in the confines of the gorge, he's only got one choice.
Hatari is the only other prime male in the group, so even though he is the chimp most likely to stab Brutus in the back, the two have to have some kind of relationship.
A bit of grooming eases the tension between them.
But it won't last.
Looking ahead, it's hard to imagine how the testosterone-driven males will cope when the old females die and aren't replaced.
While there's no corridor to bring new females in, and no sign of baby girls, chances of a happy future are slim.
The oldest females are in their 30s and 40s.
It's possible they still remember the other chimps from the big forest.
Chimps are intelligent, but is it possible for them to share memories from the past? If not, when the grannies die, that knowledge will die with them, leaving the youngsters without a clue.
They will think they are the only chimps in the world.
Maji is the boldest teenager in the group.
He's young but he's already one of Brutus's sidekicks.
On the cusp of adulthood, he loves following the big males.
But he'll also jump at the chance to hang out with his young friends.
Being carefree is all very well, but because there's a huge shortage of males in the gorge, Maji will have to grow up fast.
He'll have to be ready to take on a role in Brutus's team.
Today the boys have a taste for blood.
Trapped alongside the chimps are black-and-white colobus.
The Kyambura chimps love to eat them.
This is where the males' teamwork is essential.
Brutus and Hatari have to work together.
Colobus monkeys are fast and clever - success is not guaranteed.
Teenage Maji is keen to join in.
If he wants to help, he'd better be up to the job.
The quarry is in their sights.
And the chase is on.
WHOOPING Baby monkeys are the target but a male colobus will fight to the death for his family.
Getting past the protective dads is no easy task.
Brutus pushes the monkeys into position, straight towards a waiting Hatari.
They'll be no match for his strength and aggression.
The colobus can go no further.
They're cornered.
Hatari's trying to get to them, but teenage Maji keeps getting in the way.
Hatari prepares for the final charge but Maji blocks his path.
The hunt is over.
It's been a disaster.
Brutus's disappointment is intense.
The chimps have wasted a lot of energy, and it's all Maji's fault.
If the Kyambura chimps can't function as a good team for a simple hunt, it doesn't bode well for their future.
Hatari, however, hasn't come away empty handed.
In the confusion he did manage to catch a baby.
He slips off to eat it alone.
By sneaking off and not sharing the spoils, Hatari is showing his true colours.
Chimps don't need meat to survive, but they love the taste as much as they love the thrill of the hunt.
Because hunting for monkeys requires so much energy, the chimps only do it when times are good and fruits are abundant.
Right now in the high season, the gorge is a lush paradise.
Their gorge is five miles long and full of ancient unlogged forest.
It might be their prison but at the right time of year it must seem like being trapped in heaven.
A good, rich habitat like this can improve the breeding rate for female chimps.
And Emiti is showing signs of coming into season.
A female chimp in oestrus causes excitement in the group.
This mother has a record for fast breeding.
If she can do it again, there's every hope this time for a girl.
Female chimps will mate with any number of males, even the youngsters, and Hatari isn't going to miss his chance.
She might have just conceived.
With any luck, there's a little girl on the way already.
Brutus and his team are on foot patrol.
They regularly march the length of the gorge, checking on the progress of fruiting trees.
Keeping everyone fed is a full-time business.
The ancient forest here in the gorge is planted by the chimps, who disperse seeds as they feed.
They are essential to the eco-system.
The very health of the forest depends on their existence.
They can march eight miles a day looking for food.
Brutus and the males always go ahead.
It's their decision-making that leads the community.
While the boys are on the march, they're also looking out for hostile parties of male chimps.
After all, a patch of forest as lush as this would normally need defending from invaders.
The irony is that Brutus and the others don't realise there's no chance of finding trespassers here.
As the savannah that traps them in also keeps warring chimps out.
Brutus might be wasting his time, but today he hasn't wasted his energy.
A lucky find produces some honeycomb.
With his attention caught up in the sticky sweetness, he takes his eye off his real enemy.
The older Hatari gets, the closer he is to challenging Brutus for his alpha status.
But until he's ready he has to be satisfied with dominating the females, especially when Brutus isn't looking.
He has spotted little Pamba, the teenage female who is approaching maturity.
Hatari has her cornered, and she's very frightened.
Even though she isn't yet at peak fertility, Hatari could still force her to mate, and that could involve a beating.
PAMBA SCREECHES Her terrified screams alert Brutus, who recognizes the challenge to his power.
He won't stand for this sort of behaviour.
At the sound of Brutus approaching, Hatari slinks off.
He is still too much of a coward to challenge Brutus directly.
But it's only a matter of time.
Unless the Kyamburas are rescued soon, it doesn't matter who's in charge here.
Neither Brutus's experience nor Hatari's strength can lead the community to safety across the savannah.
Only humans can stop the gorge falling silent and at the moment there's no sign of any assistance.
Driven by her instinct to leave the group and go in search of other males, teenage Pamba has climbed to the edge of the gorge.
She has two choices - make a bid for freedom and risk her life, or stay with her community and face an uncertain future.
Maji the teenage male has followed her.
He's wondering what she's up to.
What can Pamba be thinking? Does she understand her options? Whatever she's thinking, she can't sit there all day.
Maji climbs down, and Pamba is decided.
Her urge to leave overrides her fear of what lies beyond, and she takes her first tentative steps into the outside world.
She's brave.
She's risking her life.
If she makes it, she'll be saved.
And she's gone.
On the cusp of adulthood, Maji has been independent from his mother for some time.
He's full of enthusiasm for life but he still lacks the skills to make a useful contribution to the team.
In the dense undergrowth of the gorge a baby bushbuck is frozen still.
Maji spots it, he creeps in and the fawn's instinct to keep still is its undoing.
Maji reaches into the bushes.
He makes his first kill.
Whether he meant to kill it or not, the community would relish this meat.
But Maji seems confused.
He doesn't know what to do with the body.
If only Brutus were here to show him.
But Brutus doesn't know what's happened.
SCREECHING He's calling his family ready to move on.
Realising he's been left behind, Maji leaves the dead bushbuck to rot and rushes to catch up.
The teenager still has a lot to learn.
Until he grows up, he's little use to Brutus and his family.
The sun sets early on the Equator.
If she's still out there, Pamba will struggle to find a safe place to sleep.
How will she survive the night alone? At night the gorge is no longer a place of sanctuary.
Maji and his family build nests high in the trees for safety.
They have to be off the ground before it's dark, as the gorge never sleeps.
Herds of elephants come in to drink.
Hyenas patrol the pathways, looking for prey.
None of these creatures would be fun to run into.
Pamba had better be off the ground if she wants to see another dawn.
Brutus and his boys once again make their way out into the savannah.
Their instinct for patrolling their borders has drawn them out to the very edge of their territory.
Despite never having met a strange male, Brutus still insists on making the effort.
Perhaps he thinks one day someone is bound to come, and if they do, Brutus will be ready.
But protecting their community from imaginary marauders is a risky business, when it means entering lion country.
Chimps are one of the most intelligent animals on the planet, but if they knew how fast the clock was ticking, surely they'd be trying to escape instead of looking for non-existent enemies.
But they carry on regardless.
For as far as the eye can see, there is never another chimp in sight.
But that doesn't mean the area is void of life.
Their furthest boundary goes right by the human villages.
Human beings can be as dangerous to chimps as lions.
Brutus is really pushing his luck here.
But he continues with his motley crew on their patrol through the tall grasses.
Occasionally standing up on two legs to give themselves a better view.
There are some theories of evolution that claim our ancient chimp-like ancestors found themselves in isolated patches of forest surrounded by seas of savannah.
And it was adapting to this new and different habitat that caused them too to stand on two legs.
The start of a journey to becoming human.
Could the Kyambura chimps' adventures in the savannah be an echo of what happened millions of years ago to our own prehistoric relatives? Today it's not just the boys that have ventured out.
Even the mothers and babies have made it over the top in search of precious figs.
Perhaps the longer the chimps spend in the border between forest and savannah, the more they will begin to adjust to the environment.
Could this be evolution in action? If they can adapt to a savannah lifestyle, perhaps their future looks brighter than expected.
But predators like lions are not the only dangers in the grasslands.
Far out in the savannah a spark ignites the grasses.
The plains burn year after year in the dry season and the flames can be ferocious.
If the chimps didn't have the refuge of the gorge, they could be burnt to death out here.
They'll never become savannah creatures.
With no escape from their prison in sight, Brutus and the chimps are facing another 20 years inside.
If they're to survive it, their luck needs to turn.
Safe inside the gorge, Emiti relaxes with her toddler.
It's been a while since she last came into season, which is a good sign she might now be pregnant, and with teenage Pamba gone, all hope for a baby girl now rests on Emiti's shoulders.
THUNDER ROLLS Rain comes in from the hills and electricity fills the air.
It's contagious.
CHIMPS SCREECH The wet season is finally here.
The river swells and the gorge once again becomes a place of abundance.
And just as well.
Emiti is definitely eating for two and needs all the nutrition she can get.
The new wet season means the chimps are once again full of energy - bad news for the local colobus.
The hunting season has started.
Maji spots an opportunity.
This time he doesn't waste it.
He initiates his first hunt.
The male colobus try to frighten him off.
He's not much bigger than they are, but he bravely carries on, and calls out for the rest of the team.
Reinforcements arrive.
Brutus and Hatari are here to finish the job.
The whole family joins in.
The catch is a good one.
There's more than enough meat to go round.
A hunt like this really brings the community together.
But no-one shares with Hatari.
His bad behaviour has come back to haunt him.
If he really wants a crack at the title he'll have to make friends, not enemies something he's yet to learn.
Teenage Maji enjoys the tail.
He showed real signs of growing up in the hunt, but he still can't resist playing with his food.
And there's another young chimp enjoying the spoils here that hasn't been seen for some time.
It's a teenage female.
There's only one chimp it could be.
Little Pamba.
She's alive.
Her escape across the savannah has failed.
What she's been through we'll never know.
But at least she's safe and her return is great news for the community.
For chimps this desperate for babies, every female is of great importance.
She's returned just in time for a share of the meat.
Heavily pregnant Emiti is the only one who's not here now.
Hopefully, she's taken herself off to give birth.
After their feast the Kyambura community is content.
Brutus shows his softer side and the family relaxes together.
Pamba and Maji play.
They show no signs of straying today.
Perhaps Pamba's urge to leave is passing.
Brutus has held his throne for another year, and kept his motley crew of males busy.
But Hatari gets stronger by the day.
The showdown between the two will happen soon.
But at least for the moment there's peace among the males.
And there is one other small sign of hope.
Emiti has returned and, sure enough, there's a tiny baby clinging to her fur.
Barely a week old, it's helpless and can have no idea about the claustrophobic world it's been born into.
Emiti has done it, she's produced a daughter.
The little girl brings new hope.
She will make all the difference to the Kyambura chimps.
They've survived the year, and in the gorge that's the best they can do, take each day as it comes, and resist extinction until salvation comes to find them.
The Kyambura chimps' story is a sad one, but it's not unique.
They're lucky, as they're protected by the Uganda Wildlife Authority.
But as forests everywhere decrease in size, some chimps are finding themselves in direct conflict with their human neighbours.
150 miles north of Kyambura, chimps are running so short of habitat they're forced to raid human crops, and get trapped in snares.
It takes a dart and an anaesthetic to get them off.
It's dangerous.
The forest environment is far from ideal for complex clinical procedures.
But they have to do it, otherwise the chimp will die.
The chimps that get saved like this are the lucky ones.
Many others are never found.
Good job, guys, good job.
Peter Apell from the Jane Goodall Institute is working at the sharp end of chimp conservation.
He's fed up with pulling snares off chimps, so he has a vested interest in reducing the conflict between chimps and humans.
You see that? The thing about this snare is that the harder you pull, the tighter it gets.
Eventually, what the trapped chimpanzee will try to do is try to break this branch.
You see how tough that is? It is really, really strong.
But eventually, after days of trying, they'll succeed, and then they'll move around the forest with a piece of that branch tied on to this snare, that is around their wrist, and unless that chimpanzee is saved, they could die.
Peter is tired of patching up injured chimps, so he's begun a programme that addresses the cause, not just the symptoms, of the plight of chimpanzees.
Right now we're on the edge of Bugoma Forest Reserve, which is one of the last remaining chimpanzee habitats in Uganda.
Just north of Bugoma Central Forest reserve is Wambaya Central Forest Reserve.
Several years ago these two forests were connected by riverine forests and chimpanzees used to move freely between the two forests, allowing for the possibility of exchange of genes.
For chimpanzees, connectivity is very important for the chimpanzee population to survive.
What we've realised over the last five years, there has been continuous and consistent destruction of this corridor by communities in order to sustain their livelihoods, in order to sustain their wellbeing.
The forest has been totally cut down and what that has resulted in, more and more siltation of the river bed, and that has drastically reduced on the quality and the quantity of water within these rivers.
Households which would fetch water right next to their home, now have to travel several kilometres on a daily basis.
The villagers are at risk of disease by drinking from the filthy water.
But there is no alternative.
Because the forests are being destroyed, the rivers are being spoilt.
Ten years ago, this river, which is only just about one metre in width, was about 20 metres in width, extending from this end of the bank to the other end of the bank.
And from talking with people who have been here over the last ten years, they said the river used to be at least one metre deep.
If we can restore the forest then this river can recover and will provide a vital water source for this community.
So here in Hoima district, both humans and chimps are depending on forest recovery.
We are planting approximately 230,000 tree seedlings in this nursery.
Trees are a very important part of this community.
The community uses trees as a source of fuel, and as a source of wood for construction.
So by running this project we will be addressing two main needs.
One, conservation needs, by re-establishing the corridor, and livelihood needs for this community.
The community owns this project.
The land on which the nursery is being established was donated by the community and, as you can see, the community is involved on a daily basis.
All this is done voluntarily.
The reason that the community is volunteering their time, volunteering their land towards the establishment of this nursery is because they realise that they are the beneficiaries.
These trees will be given back to the community to establish their own wood lots and to help re-establish the corridor through replanting the degraded parts of the riverine forest.
It's a mammoth task and trees like this will take up to 30 years to mature.
But, for the chimps in this part of Uganda, at least the work has now started.
If we get it right here then we shall have a template that we can replicate to reconnect several fragmented populations around Uganda, like the chimps in the Kyambura Gorge, that are in desperate need for reconnection.
With projects like this one starting up, there is some hope for the Kyamburas' future but they'll need to survive for at least 20 years before they get their own corridor.
Luckily for them, they're under the protection of the Uganda Wildlife Authority.
Monitored daily, they're visited by tourists, who are excited to catch a glimpse of these great apes.
They bring welcome revenue, which is a big boost to the local economy.
The Kyambura chimps are hanging on in their bizarre savannah and forest existence.
The next 20 years will decide the fate of these chimps.
Let's hope their closest cousins get a move on, and rescue them, before the Kyambura chimps are lost for ever.