In the heart of Africa,
straddling the borders of Rwanda, Uganda and Congo,
lies a remarkable mountain kingdom.
It's home to the world's last 700 mountain gorillas.
With so few left,
they require constant surveillance from a dedicated band of humans.
Our cameras have been given privileged access
to these amazing animals by the people
that record every detail of their lives.
In this programme, we'll discover
what it takes to be a dominant silverback.
Every group needs one. GENTLE HOOTING
Every male aspires to be one.
The true leaders of the gorilla world.
Join us as a teenage silverback fights to find his place in a group.
An orphan's fate hangs in the balance.
And the world's most successful silverback
faces the biggest challenge of his life.
Of the world's last 700 mountain gorillas,
less than 65 are dominant silverbacks -
every male gorilla's ultimate aim.
And it's a prize worth fighting for -
the right to father the next generation.
Some males will never succeed.
But that doesn't stop them trying.
And no-one stays at the top for ever.
From these 65 dominant silverbacks,
one has remained at the top for longer
and sired more offspring than any other.
The true king of the volcanoes.
His name is Titus,
and today is his 35th birthday.
Titus is now the oldest known silverback in the world.
But his years as a great leader may be coming to an end.
A silverback is only as successful as the group that he leads...
..and Titus's group has been decimated.
Three years ago, Titus led his group of 25
to the very top of their volcano.
He was driven there by a rival silverback
set on taking Titus's crown.
On top of their volcano kingdom, his group was forced to choose...
..between Titus,
the older, more experienced king,
and the younger, stronger silverback.
19 of his followers left with the challenger.
Just six gorillas chose to stay loyal to the ageing Titus.
Three years on, and Titus is about to face the biggest challenge of his life.
This time, the threat will come from a gorilla
much closer to him than anyone yet realises.
CHEST BEATING
Chest beats can carry for over a kilometre.
CHEST BEATING
They allow males to assess each other's size and strength.
CHEST BEATING
Somewhere out there is a large, strong silverback -
and he's heading Titus's way.
40 kilometres north, separated by swathes of farmland,
there's a silverback at a very different stage of life from Titus.
Rukina is in his prime.
At 25 years of age, he controls his group
with the confidence of a born leader.
Rukina's home is Bwindi Impenetrable Forest.
Smaller than the Isle of Wight,
and higher than the tallest mountain in Britain,
it's home to about half the world's mountain gorillas.
Bwindi lies in southern Uganda,
just 40 kilometres north of the volcanoes
where Titus and the other half of the population reside.
On Rukina's trail is Martha Robbins,
a pioneering scientist who's dedicated 20 years of her life
to studying the world's last 700 mountain gorillas.
I realise I definitely don't have the average day job.
My commute involves walking into the forest,
and this is the most amazing office anybody could have.
Martha was the first researcher to gain the trust of a gorilla group in Bwindi,
and today, she's still the only scientist studying this precious population.
Research is important for many reasons that contribute to conservation.
We need to understand their ecology, their social behaviour,
and just how they develop over time, to help conserve them.
Martha meticulously documents the lives of all the gorillas.
But she's particularly interested in the fate of the silverbacks.
One of the aspects that interests me the most is how males become dominant.
All males, when they become adult, they turn silver.
So all males become silverback,
but not all males become leaders of a group.
I sort of view it as, you know,
in a business, very few people become the CEO.
So becoming a dominant silverback's a very difficult thing.
Rukina is a silverback at the very top of his game.
It's the start of the dry season,
and he's leading the group to their local swamp.
They'll eat over 20 kilograms of vegetation a day.
Rukina has guided them well,
and the gorillas sing with delight at their new feast.
GORILLAS CROON
On the outskirts of the group, Martha spots a surprise visitor.
It's junior silverback Marembo,
a teenage male on the cusp of adulthood.
He's a gorilla Martha knows well.
Until a few months ago, Marembo lived happily in Rukina's group,
a fine role model for the younger gorillas.
But on becoming a teenager, his hormones took control
and he struck out alone in search of females and a group of his own.
Now he's back to try his luck against the dominant silverback, Rukina.
Martha doesn't fancy his chances.
Rukina's definitely still in his prime.
Marembo's about 14, 15 years old,
and he's got a way to go before he's...he's a threat.
With his raging hormones and desire to be dominant,
Marembo's return is sure to shake things up.
And no-one quite knows how Rukina will react.
While Martha's research in Uganda focuses solely on Rukina's group,
further south, on the Rwandan volcanoes,
a much larger operation is in action.
Every day, teams of trackers, field staff and researchers
climb the volcanoes to collect
behavioural data from the nine different gorilla groups they study.
The teams are from Karisoke Research Center,
established over 40 years ago
solely to study mountain gorillas.
Come rain or shine, these gorillas are visited every day,
on Sundays, holidays and even Christmas,
making them some of the most studied animals on the planet.
Only through detailed, long-term observations like these
can the lives of mountain gorillas really be understood
and this precious population preserved.
At the head of this 70-strong team is 32-year-old Felix Ndagijimana.
Felix is on his way to see gorilla king Titus. All is not well.
Felix has met the mystery silverback
responsible for the distant chest beats.
He's young, strong and alone.
LOW-PITCHED EXHALATIONS
Felix knows if this silverback meets the ageing Titus,
there'll be trouble. THROATY GROWLING
Always, you don't know what the outcome's going to be.
You know, sometimes it just gets like very physical -
they will fight and bite each other.
Just 100 metres away, Titus and his group are feeding,
oblivious to the impending threat.
Titus may be old, but he's no stranger to adversity.
He's survived through some incredible ups and downs,
each one recorded by his human observers
since the very day he was born.
From these notes, we can reconstruct
the story of Titus's extraordinary life.
When Titus was four years old,
barely weaned from his mother's milk,
he witnessed the brutal murder of his father.
The great silverback
was shot in the chest while defending Titus and his family from poachers.
The group was sent into turmoil.
Without a dominant silverback,
the gorillas became frightened and confused.
In the chaos, Titus's mother fled.
The four-year-old Titus was orphaned.
Everyone believed his short life was over.
But Titus didn't die.
He was adopted by a totally unrelated silverback.
The silverback treated Titus like a son.
He was offered shelter
and protected against the other males in the group.
Titus is a born survivor,
and he grew to be a great and powerful leader.
Today, Titus has the same fighting spirit.
But he's a grandfather figure, and his life has come full circle.
In a remarkable twist of fate, he now cares for a young orphan gorilla
whose mother has left the group.
This orphan is alone in the world, as Titus was once,
entirely dependent on the ageing silverback for warmth, shelter
and, above all, protection.
But Titus's age makes the pair vulnerable.
The approaching silverback will attempt to
seize control of the group... CHEST BEATING
...and could kill an infant fathered by another male.
The orphan's survival depends entirely on Titus's ability
to remain at the head of his group,
and fight off this impending threat.
Martha leaves her house each morning at 7:00,
and heads to where she left the gorillas the previous day...
a walk of anything from 90 minutes to four hours.
Martha's keen to catch up with the young silverback, Marembo,
last seen following Rukina and the family into the swamp.
On the edge of the group, Martha finds a silverback
lying in the shade.
It's the teenager, Marembo, and it looks like he and Rukina
have already come to blows.
You can see the bite wound on the back of his head.
He's had a tough time of his life.
He would like to be dominant, but he certainly
has a long way to go before he's strong enough.
And Rukina's really in his prime,
so he may try and stay on the edge, or he may leave.
We'll have to see.
While young Marembo sulks under the bushes,
dominant silverback Rukina enjoys a real gorilla delicacy...
..Dead wood.
The wood is high in sodium, a precious mineral for gorillas.
As the gorillas gather, it gives Martha a chance
to have a look at the dominance hierarchy within the group.
Sometimes you'll see somebody just sitting on the edge
and you think they're just resting,
but actually they're waiting their turn.
Marembo keeps a respectful distance from Rukina.
He's very much bottom of the pile.
Even the females rank above him.
If Marembo stands any chance of becoming a gorilla leader,
he needs to start at the bottom and work his way up.
And he's spotted his first target.
This male was orphaned as an infant.
He's the most timid member of Rukina's clan.
It's teenage Marembo's big moment.
He positions himself between the male and the rest of the group.
It's a cheap trick to show Marembo's dominance.
Eventually, the nervous male scoots past.
For Marembo, it's a small triumph.
At least he's dominant over someone!
1 gorilla down, 13 to go.
GORILLA CALLING
CHEST BEATING
Back on the volcanoes,
Felix is on his way to find silverback king Titus.
SHRIEKING
But there's trouble.
HOOTING
The big, challenging silverback is now amongst the group.
He's set on one thing...
...seizing Titus's throne.
HOOTING AND DRUMMING
The intruder displays to show Titus his strength.
But Titus can't be intimidated.
If he gave up now,
the rival silverback would kill the young orphan in his care.
The orphan must stay close to Titus for protection.
But Felix knows the gorilla king is past his prime.
Titus is old. He's lost a lot of muscles
and you can see that his movement, when he's moving he's very slow.
Titus now faces a potentially fatal decision.
There are two options. One is run, and the other one is stay and fight.
The old leader is wise and he's brave.
In a rare display of strength, he shows the intruder his intent.
SHRIEKING AND GRUNTING
Silverback king Titus isn't going to give up his group without a fight.
While Titus faces the biggest challenge of his 35 years,
in Bwindi, everyone is still waiting for rain.
All the inhabitants are ranging further each day in search of food and water.
LOWING
Rukina and his group have been forced into dangerous new territory.
Oh, he's got a big cut.
Oh, he's got a very big cut on the top of his head.
That has to hurt.
Marembo's right here,
and he's got a very big, new bite or cut on the top of his head.
It's maybe about this long, so I think he's been in some fights.
Marembo's deep wounds
look to be made by the sharp canine teeth of another silverback.
But these wounds weren't made by Rukina.
Martha follows the trampled vegetation
until she finds another silverback.
It's a gorilla she doesn't recognise.
It's definitely not Rukina.
And he's not alone.
Four hostile silverbacks are threatening Rukina's group.
Rival males will fight to steal females...
..and it looks like teenage Marembo
got injured trying to prove himself defending the group.
But Marembo isn't the only gorilla at risk from the rival males.
Martha spots the youngest member of Rukina's group,
eight-month-old Ponoka, and his mother, Tinda.
Silverbacks will kill infants that are not their own...
SHRIEKING
..an act known as infanticide.
Killing Ponoka would enable them to mate with the bereaved mother
and sire offspring of their own.
Ponoka and his mother are dangerously close
to one of the rival silverbacks.
It's the dominant male from the other group.
With Tindamanyere and Ponoka being up here,
the infant's very vulnerable, at that age, to infanticide.
RUMBLING GROWL
On the volcanoes, Felix is heading towards Titus.
GRUFF EXHALATIONS
He's received worrying news.
Titus and the rival silverback have come to blows.
The gorilla king appears to be unscathed...
..but his rival is nursing two fresh wounds...
..wounds made by Titus.
Finally, Felix gets a good look at Titus's challenger.
He recognises his face.
It's Rano...
..Titus's son.
Banished from the group three years ago,
he's now returned from the wilderness
to claim his father's throne.
In the years he's been gone,
he's grown into a formidable silverback.
HOOTING
Rano piles on the pressure.
Titus keeps him at arm's length.
But Titus is too old to risk another fight...
..and he's left with one option.
He must flee...
..and his small but loyal group follows.
The long pursuit begins.
Felix knows that Rano aims to drive the ageing Titus to exhaustion,
then take the group himself.
Sometimes he's behind them, he's displaying, he's following them.
They're going to keep moving.
The little orphan must stay out of Rano's reach.
There'll be no time to eat
and no time to rest.
But Titus can't keep running for ever.
SHE MURMURS
In Bwindi, Martha is worried
for the youngest and most vulnerable member of Rukina's group...
..eight-month-old Ponoka...
..last seen near a silverback from the hostile group.
Now he's nowhere to be seen.
Teenage silverback Marembo is on the front line,
doing his best to keep the rival males at bay.
SHRIEKING
Martha has finally tracked down dominant silverback Rukina.
And he's got problems of his own.
Two of his females seem to be showing a little too much interest
in the chest beats from the other group.
Both of them are looking towards the sounds of the other group.
These females may try to sneak away to join the other group.
Rukina will do everything he can to stop them.
This is a time where Rukina is likely to be very vigilant
to make sure that these females stay with him.
RHYTHMIC GRUNTING
Rukina knows these females can't go anywhere while he's guarding them.
So the wise leader holds his ground,
while foolhardy Marembo does the fighting on his behalf.
CHEST BEATS
Surprisingly, young Marembo's efforts seem to be working.
The chest beats from the other group fade away into the forest.
CHEST BEATS
Bruised and battered, Marembo is exhausted.
But, for one little gorilla,
Marembo's efforts have been worthwhile.
Little Ponoka is back,
none the worse for wear.
But it's his mother that Marembo is trying to win favour with.
And she doesn't seem the least bit impressed.
It's only with the respect from the group
that a silverback can become a great leader.
Marembo's quest for dominance doesn't look good.
GRUNTING AND CHEST-BEATING
THEY TALK QUIETLY
Back on the volcanoes, there's even more trouble for Titus.
So the situation is that there's another silverback up there.
The group is here and the other silverback is up there.
It's not Rano, it's another silverback.
CHEST BEATS
GRUNTS REASSURINGLY
Titus is under incredible pressure from his son Rano,
and now there's another challenger for his crown.
You can imagine how this is stressful for Titus.
He already has to deal with this one,
and then this other silverback here.
It's too much for him.
GRUNTING AND CHEST-BEATING
I can see him.
HE GRUNTS REASSURINGLY
CHEST BEATS
Rano's displays are becoming more frequent,
but this time they're not directed at Titus.
His chest beats carry across the mountain,
telling the second challenger that Rano got here first.
Rano's displays keep the new impostor at bay.
Titus's son is stamping his claim on his father's group.
CHEST BEATS
Rano's campaign has been relentless,
and it seems to be paying off.
But what does this mean for the ageing king?
Titus and the little orphan are exhausted.
They've been on the move for ten days.
Felix can see the tide turning.
The orphan sticks close to Titus.
But the ever-present threat from Rano is just metres away.
And one of the young males seems to be accepting him into the group.
For Titus, this is no longer a battle
for the leadership of his group.
It's become a battle for survival.
His life and the life of the little orphan now hang in the balance.
In Bwindi, Rukina and his group are waking to another sunny day.
Martha spots teenage silverback Marembo.
He descends from his treetop haven and reluctantly follows the group.
His heroic efforts to keep them safe have been completely ignored.
The group has found a tree covered in bracket fungi.
As always, Rukina is first to help himself...
..before moving off to enjoy his prize.
MEWING
Little Ponoka steps up to take his turn.
Marembo watches from the sidelines.
Even the youngest member of the group gets to feed before him.
The injustice is too much for one gorilla to bear.
As if to rub salt into the wound,
Rukina is flaunting another privilege of the dominant silverback...
..right under Marembo's nose.
Rukina leads the group away into the forest...
..very much a silverback in control.
But, for once, Marembo doesn't follow.
The teenage silverback chooses a different path...
..and walks alone into the forest.
Martha suspects that this time his departure is final.
He's no match for Rukina and is off to seek an easier target.
It may be Marembo will never become a gorilla leader.
But one thing's for sure...
like all young males, he'll never stop trying.
On the volcanoes, there's no reprieve for Titus.
The pressure from his son Rano is relentless.
Felix has been monitoring Titus's health,
and it's taken a turn for the worse.
He's called in Magda, the gorilla doctor.
She's part of an elite team of seven vets
who treat the mountain gorillas if their lives are at risk.
Today, Titus is her priority.
He's exhausted and has picked up an injury.
Felix leads Magda to the group.
She makes reassuring noises to let them know she's coming.
Oh, he's nursing his right hand.
Instead of putting it like this, he puts it like this.
There must be something here.
Magda has spotted a deep wound across Titus's wrist,
making it hard for him to walk.
SHE GRUNTS REASSURINGLY
Now you can see the wound under his knee, under his right knee.
There's always a little worry,
especially with the older silverback like that,
that there can be infection, there can be some deeper tendon injury.
The battle scars from Rano's campaign are starting to show.
You can see that their tummies
are not as full as they would be normally.
This is siesta time, but they can't afford siesta now
because they were running since morning, so now they have to eat.
As a gorilla doctor, she hopes to save every animal.
But some cases are beyond her control.
Magda can do nothing.
To anaesthetise and treat Titus now would mean a sure victory for Rano.
It's with heavy hearts Magda and Felix leave Titus for the night.
Nature must take its course.
Back in his office, Felix records the events of the last few weeks...
..the latest chapter in the 35-year story of Titus's life.
Titus has shown what it takes to be a great silverback leader...
..a gorilla who came from humble beginnings,
who, on the slopes of the volcanoes, rose against much adversity
to be the most successful silverback ever recorded.
He's sired more offspring
and lived longer than any other known mountain gorilla.
He's protected his group until the end...
..eventually hounded to exhaustion by his own son.
I don't know how long Titus can keep going.
This could be the end of Titus.
But the legacy of Titus will live on.
The fate of his group now rests with his own flesh and blood.
At first light, Felix climbs the volcano
to see Titus for what could be the last time.
HOOTING
Rano remains strong and determined.
For weeks, he's intimidated, terrorised
and wounded his own father.
Soon the prize of dominance will be his.
Titus has finally managed to rest...
..surrounded by his most loyal followers.
The little orphan gently cleans his wound.
Titus is dying.
Felix has borne witness to a momentous event...
..the crowning of a new silverback...
..and the last stand of the Silverback King.
Next time on Mountain Gorilla...
...we look at what the future holds for one of our closest relatives.
Are they safe in our hands?
Titus' group struggles to accept a new king...
..and Rano leads them into trouble.
And with Titus gone...
..the little orphan's life hangs in the balance.
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