The Pygmy Hippo: A Very Secret Life Natural World

It's one of the world's most appealing creatures...

..and one of its most mysterious.

There are around 350 pygmy hippos living in zoos,

but in the wild, they are endangered and notoriously hard to find.

Now, a young ecologist is taking on what might be mission impossible...

..to unravel the secrets of an animal few have ever seen

and about which we know so little.

She'll spend months deep in a remote West African rainforest...

facing its many hazards,

as she attempts to get a glimpse of its elusive behaviour,

understand how it uses its forest home,

so that ultimately,

conservationists can work out what the pygmy hippo needs to survive.

-THEY GASP

-Oh, my God!

Meet Gloria.

She's a three-month-old baby pygmy hippo.

Gloria likes messing around, exploring and taking a nap.

She lives with her mum, Wendy, in Marwell Zoo.

But for wild pygmy hippos, life is not so rosy.

Their forest home is disappearing at an alarming rate

and at the moment, all we really know about them

is what we know from captive hippos, like Gloria and Wendy.

Australian Wei-Yeen Yap is a vet, a wildlife ecologist

and passionate about pygmy hippos.

They're just so gorgeous.

How can you not fall in love with this?

The hippos' secretive and reclusive behaviour in the wild

makes them hard, if not impossible, to study.

But the clock is ticking

and Wei knows scientists must find out much more about them

before it's too late.

If we want to try and attempt to save them,

then we have to know how they function

and what they need to survive,

in order to come up with some kind of plan.

Pygmy hippos are on the internationally recognised Red List,

with officially just 2,000 to 3,000 left.

Living in a region of West Africa recently blighted by civil unrest,

their numbers could be much lower.

Today, pygmy hippos are found in just a few isolated pockets

of what's left of the Upper Guinea forest.

The largest surviving protected population

is in Cote d'Ivoire, in the Tai National Park.

Wei has experience of studying hard-to-find rainforest animals.

Now, she's joined forces with local conservationists

in an international effort to help solve

one of the natural world's last great mysteries.

Amazingly enough, there are some animals left in the world nowadays

that we still don't know almost anything about

and the pygmy hippo is one of them.

Leading the Tai Hippo Project

are Professor Inza Kone

and Dr Karim Ouattara.

It is very, very difficult to see the pygmy hippo...

These animals are nocturnal,

very lazy, very cryptic, so very difficult to follow and study.

I think this is one of the challenge that Wei-Yeen will face.

Research assistants Donatien Bele...

and Leon Sio Toh...

have 18 years' forest experience between them,

but even they have only glimpsed a pygmy hippo.

Everything with this animal is hard.

It makes every little thing that we do manage to achieve

really, really exciting.

Wei's new home will be a dilapidated research station

in the remote forest, five hours from the nearest big town.

Building a case file on this notoriously difficult animal

will be anything but easy.

The pressure is on.

Understanding more about the pygmy hippo's very secret life

is the first step to being able to protect

its long-term future in the wild.

The big thing for us is to just start really simple

and just start with getting a really basic, clear, simple idea

of what pygmy hippo behaviour and ecology and density is,

and what is really important to their survival.

The enormity of this mission impossible task

is starting to dawn on Wei,

as she spends the first two months looking for clues.

The water's really high at the moment,

but we found fresh tracks all along this little exit-entry point.

So, I've just come back to check it out again.

It's a really perfect area for the hippos.

You can see the river's deep enough

that he can get fully submerged in here.

Pygmy hippos can be just a tenth of the size of the common hippo.

Both are amphibious, but unlike their larger cousins,

pygmy hippos are thought to lead a solitary life -

adults only meet to mate.

To add to Wei's challenge,

they are believed to hide in water by day and are most active at night.

We've got a print here,

which you can see the two main big phalanges

and then the two little residual ones.

And then further up here,

we can see he's exited out of this river bank here

and it's not that great

but you can see his two phalanges again, here,

as he's made his way up.

I'm looking in certain places.

I'm trying to think like a pygmy hippo

and it seems, at the moment, to be working.

The Tai National Park

is the largest protected tranche of primary rainforest

left in West Africa.

It's home not just to the pygmy hippo,

but to many other rare animals.

With a staggering 140 species of mammal alone,

the park's amazing array of flora and fauna

has earned its World Heritage Site status.

There are 12 different primates,

including the vulnerable Diana monkey.

But illegal poaching

and gold mining is increasing the pressure on the park's wildlife.

Cote d'Ivoire already has

one of the highest deforestation rates in the world.

It's lost almost 70% of its original forest cover in just 50 years.

If you look at the original home range of pygmy hippos

in Cote d'Ivoire, we see that most forest areas

have just been destroyed, converted to industrial plantations.

And when plantations are so close to the forest, this is a direct threat.

Deforestation, plus cocoa, coffee and rubber plantations

continue to threaten forests like Tai,

one of the last strongholds of the pygmy hippo.

Wei is thrilled to find what she thinks are fresh pygmy hippo tracks,

but catching sight of who made them will be a much bigger challenge.

Wei and the team have set up remote cameras with night vision.

She's checking what they've captured.

It's a fascinating home movie of the inhabitants of the Tai Forest.

There is an African civet...

..a water chevrotain...

..white-breasted guineafowl...

..and a particularly nosey sooty mangabey.

The largest of the eight species of forest antelopes called duikers

is the Jentink's duiker,

endangered and nocturnal, just like the pygmy hippo.

They tend to seem to come around the same areas as the pygmy hippos a lot,

so where we have confirmed presence of a pygmy hippo,

we seem to get confirmed presence of Jentink's in the same area, as well.

We've got some leopards.

We've got this beautiful shot of a really healthy,

really gorgeous male, because you can see his back end.

Leopard...

Then...the animal Wei came to see.

So that's...amazing.

We've got this beautiful picture of a really quite large,

male pygmy hippo.

And you can see him here coming and actually sniffing the path

and kind of going, "Well, that smells like humans,

"I don't think I'll go down there today."

And he gives it a really, really good sniff,

hangs around for a quite few seconds and then decides to keep moving on.

Footage of wild pygmy hippos is exceptionally rare.

Now Wei knows where this male hippo is active, she hopes he'll be back.

That's our first confirmation so we'll put something up there

and hopefully manage to study him way more.

In 2010, a hippo with a distinctive notch in its left ear

was caught on a project camera

but Wei doesn't think it's the same hippo.

But such a distinguishing feature could help identify it...

if it's still here.

The team throws up a web of 12 cameras around the target area.

Almost anything that Wei can learn from observing the pygmy hippos

will help her build a case file.

But Wei's ultimate goal is more ambitious.

She hopes to physically capture a pygmy hippo and attach a GPS collar,

which will remotely store, then send her, a comprehensive data bank

on what the hippo's been doing, where he's been going

and when this all happens.

This could be ground-breaking new science.

To test that the radio telemetry system is working,

she's heading 20m up into the canopy, where the signal should be clearest.

Hi, Bogui? I'm not getting any signal.

'Just keep walking unless you hear that I have a signal.

-'I'll let you know.'

-OK, thanks.

Ivorian PhD student Elie Bogui is the man on the ground with the collar.

Hi, Bogui? I've got a pretty weak signal...

'So, if we mark that, that's our distance.'

OK.

With the collar working correctly,

there's time to appreciate the new perspective.

Once you've been working in the jungle for a while,

you get really stuck visually with just not seeing any horizon

and feeing really enclosed all the time.

It's actually a really big deal, psychologically.

It kind of makes you realise a whole different parallel universe

existing in the forest.

I think when I was coming up,

I disturbed a little group of pied colobus over there.

They seemed to be pretty curious and pretty freaked out by a big primate

climbing one of their trees.

So, they're staying a lot less conspicuous now,

which is interesting cos there was some red colobus

over in that clearing, over there.

They didn't seem bothered at all.

Up here, it's perfect hornbill height.

There's hornbills and instead of seeing them

flitting over a clearing for half a second,

you get to actually see them moving from tree to tree.

And somewhere, deep below the forest canopy, are pygmy hippos.

In order to collar a hippo,

first, she'll have to catch one.

It won't be easy, but Wei is undeterred.

-FRENCH:

-Pardon.

She and the team are building a series of humane traps

close to the hippo's trail.

Wei is throwing herself into the task.

TRANSLATION FROM FRENCH:

Wei isn't afraid of a challenge - she even tried to learn French

just for this mission.

..et la porte...

..a crossbeam, pour ca...

'No-one speaks any English.

'I took to learning French as quickly as possible.

'I'm probably saying completely ridiculous things a lot of the time.'

13 weeks into the mission, stage one of the plan is complete.

There are four traps built and ready for action.

Then disaster strikes.

Wei falls ill. It looks like malaria...

..a potentially fatal disease.

Despite drug treatment, she isn't getting any better...

and the nearest big hospital is an 11-hour drive away.

I'm probably going to have to get some tests run

and just make sure there's nothing else going on, which really sucks,

because the traps are built and ready to go,

our trapping date's set for the next few days and...

it's all a real big bummer.

Wei is finally persuaded to go to hospital,

where it's confirmed she has both malaria and a stomach bug.

She's hospitalised for several days,

by which time the capture team has arrived,

but is now behind schedule.

Veterinary anaesthetist Dr Tim Bouts

and postgraduate student Gabriella Flacke are now eager to get started.

This is ketamine, which goes here. The ketamine...

It's nearly 30 years since anyone attempted

to anaesthetise wild pygmy hippos.

Your dose for Medetomidine?

20mg, and 300...

Tim is experienced in captive pygmy hippo sedation

but he knows that this part of the capture process is the most risky.

If you speak with someone in Ivory Coast,

they said last time it happened, all the pygmy hippos died.

I am sure it wasn't like that,

but this is the general feeling here on Ivory Coast.

So, the fact that they allowed to do this

was a big step for the Ivorians.

Always test it on yourself first.

And this one then fits,

if you really have to breathe for the animal.

That fits at the back...

We are well prepared, we can do everything here.

We've got emergency drugs if something goes wrong.

It's always in the back of our mind but we shouldn't shy away of it,

because the possible benefits of this project are just immense.

Sedation is the only way to get a GPS collar onto a pygmy hippo.

With Wei back on her feet,

the unexpected delay means they now have only eight days to catch

one of the world's most elusive animals...

..and the clock is ticking.

The door only comes up to this high

so you can actually shoot straight through this.

That would be fantastic.

And it's easy enough to have someone else distract him on the other side.

Yeah, we'll need to have probably two people to distract

-and then hope that I don't shoot the person on the other side.

-Yeah.

You wedge it against this side and...

It's the first chance to check the traps are still working

since Wei was sick.

It's just this trap that's really, really fiddly,

cos it was the first trigger we built.

This trap, unfortunately our first trap, was real trial and error

so it's not the nicest and smoothest mechanism.

There are lots of parts where things can break,

just purely because they've been weathered.

It's a huge thing to have a trap not work if a hippo walks through it.

And there's no way they'll walk through it again, ever.

A bit more.

Merci.

-Do you guys want to see this working?

-Yes, please.

OK, who wants to be the hippo?

-Tim?

-TIM LAUGHS

OK, I look most like it!

Ce pas necessaire.

OK?

Be careful. Be really careful.

So I just walk through it now?

Yeah.

Voila! Voila!

-That was quick!

-OK.

HE SPEAKS FRENCH

It's a relief, but Karim knows that the pygmy hippo

can be a wily and wary opponent.

It is our first time we try the trap with pygmy hippos.

We have no idea now that this will work

but we hope it will work.

It's six in the evening and time to set the traps for the first time.

Wei is trying several different types of bait,

all designed to lure a hungry hippo.

So this is just salt, a lot of sea salt,

mineral salts mixed in with clay...

..so it's forming an artificial salt lick

which most herbivores find really, really tempting...

Hippos are known in captivity to eat cassava, bananas, apples, oranges,

the whole lot, but we have also been trying

other very commonly found vegetables here,

like avocados, plantain and yam.

Wei is keen to rid the yam of as much human scent as possible.

The pygmy hippo may not have great eyesight

but its nose is literally its biggest asset.

If it gets a whiff of humans, it could run a mile.

It's all set. Ready to go.

Let's go, give the hippos a chance.

Yep, he'll be waking up from his bed now.

Hopefully, he's silly enough to decide

or curious enough to decide

to walk through and eat some yam.

THUNDER CRASHES

The downpour is welcome.

As the rainy season approaches, it's thought that pygmy hippos

become more active, which might play to Wei's advantage.

At dawn, Wei gets a shock.

She knows there might be a pygmy hippo in one of the traps

on the other side of the river, but the fallen tree trunk

they've been using as a bridge has disappeared in the downpour.

There's no way the whole team can get across with all their capture kit.

The river had risen so high

that the way that we were using to cross

was completely and utterly submerged,

to the point where I got lost on the river bank for about half an hour,

trying to figure out where my entry point was.

But she can't leave a potentially distressed hippo

stuck inside the trap.

There's only one way to find out.

Swimming across the river brings its own dangers, but Wei is determined.

Crossing rivers is not exactly nice at 5am in the morning

when you're checking traps,

but if it needs to get done, it needs to get done.

A lot of other researchers just don't go into the forest

when it is like that,

but unfortunately we don't have that choice.

If we've set a trap, we can't exactly leave an animal in it.

There's no pygmy hippo in the traps yet,

but with more rain to come,

Wei needs a new plan if the river stays this high.

My only choice this morning was to swim it,

but it's not an option for the rest of the crew.

And getting all our collars and immobilisation gear and guns

and CO2 canisters and IV fluids and everything...

and ultrasound machines across...

So, I'm not sure what we're going to do.

It's vital that the team can get across the river,

so the decision is taken to build a bridge.

The pygmy hippo's forest home is crawling with other hazards.

Driver ants are one of the most aggressive animals in the forest.

Living in vast nomadic colonies of up to 20 million,

workers carve out marching paths, flanked by larger soldiers

with powerful jaws, who attack anything in their way.

Oh, God!

Ah!

They call them manya here.

And you get ant swarms and if you step into them,

there are a certain type of manya that really, really hurt!

And once they bite, they don't let go,

so you've got to rip them out,

which is what I'm doing through my pants.

I would, if I was by myself,

probably rip my clothes off right now.

A swarm of manya can kill a scorpion in a matter of minutes.

That's why you wear socks over your pants...

and I stupidly didn't wear my socks over my pants today.

It's 6am the next day

and Donatien & Leon are on early morning trap-checking duty.

We're sort of waiting right now,

in extreme suspense, trying not to stress out.

The time frames that we're having to work with

put the pressure on quite a lot.

But there's nothing we can do about it.

It's up to the hippo...and chance!

Merci, Leon...

Wei can only hope that Donatien brings better news.

HE SPEAKS FRENCH

OK. Merci, Donatien...

There's definitely a sense of disappointment,

but I suppose we need to get used to the fact that

the majority of mornings, this is what's going to happen

and so it's, push it aside

and let's get on with today.

To further understand Wei's elusive opponent, Karim arranges a visit

to the elders of several local villages.

Sharing valuable knowledge between the communities

and scientists is fundamental to the project.

Here, they are regaled with stories of an animal of mystery,

myth and legend.

If people see the tail and if you laugh, you can go crazy.

You know, you've got people that are over 70 years, 80 years,

that remember what it was like when there was rainforest everywhere

and seeing pygmy hippos was really normal.

In the second village, the elders tell them they believe

the pygmy hippo was once human, so people have a duty to protect it.

This is how they keep in mind the pygmy hippo.

It's not just in Europe, it's not just in Australia, where we go,

"Oh, they're so cute, we should save them."

It's also charismatic and has a lot of meaning here, as well.

Back in the forest, there's still no sign of any pygmy hippos

at the traps, but the cameras rigged in and around them

reveal an interesting development -

a host of other forest animals venturing inside.

Rather worryingly, they also witness thieves in the night.

Brush-tailed porcupines make off with the yams

intended to lure the pygmy hippo.

All the team can do is keep re-baiting the traps.

It's day four before Wei gets even a glimmer of hope.

She's viewed video footage through a small viewfinder of a camera

outside trap one, which seemed to show something exciting.

SHE LAUGHS EXCITEDLY

Celebration soon turns to disappointment,

when Wei takes a closer look at the images.

Unfortunately, when we went back to the computer,

we realised the door had actually triggered.

We can't figure out what exactly happened there

or what triggered that trap.

Look, it's really obvious the doors are down and it can't be....

So, he wasn't able to go through the trap,

but it IS a pygmy hippo

and he IS visiting the trap.

Can definitely see he's a male.

Yeah...and pretty relaxed.

Whether he would have gone through that day or not

if the trap had been open, we'll never know.

But the fact is, is that he's coming back to that area

on a constant basis so that's really, really exciting.

Two nights later, the male hippo returns...

Ah...

..but again, doesn't set foot inside.

Time is running out to entice him into the trap.

The capture team leaves in just two days.

I've done everything I can,

but now I have absolutely no idea what the magic ingredient

is to get this hippo to walk through this trap.

And now it's the last evening.

-Which trap was this?

-The bamboo.

Yeah, makes sense.

Wei and the capture team are spooling through the footage

from the previous night.

HE SPEAKS FRENCH

-Ah!

-THEY GASP

-Oh, my God!

-Oh, my God.

Come on...

Yeah, but look how close he is and he doesn't go in there!

-Oh, he's eating the sweet potato!

-Oh, yes!

No, no, wait...

Oh, yes! He's eating the yam.

Yes, he's eating the yam!

Oh, so close and yet so far!

That is SO awesome.

Wei is thrilled and with good reason.

It's a rare opportunity to see in close-up a creature

that only a handful of scientists have ever observed in the wild.

She also now knows that the bait works,

even though the hippo doesn't venture far enough inside

to trigger the trap.

In the trap.

He's still very, very cautious,

but he's got his entire head, up to about his shoulders,

inside the trap.

Even when he's reaching for the further yam,

he's kind of grabbing it and bringing it closer to him

and eating it there.

He's sniffing the human smells.

I think that's why he picks it up at first and he's like, "Huh..."

-Yeah, actually...

-And he's nervous.

He is nervous, yeah, cos he's really sniffing there.

With the traps already set for the final night,

Wei can only hope that he'll be brave enough to venture further in.

When dawn arrives, it brings fresh disappointment.

The male pygmy hippo did return

but he didn't go inside trap one.

The footage reveals why.

Those porcupine thieves strike again,

so that when the hippo does arrive, there's no food left to tempt him in.

It's a huge disappointment for Wei and the team.

For now, their capture plans are scuppered...

but Wei hopes she'll see more of the big male hippo in the future.

We've had beautiful footage of him

interacting with the trap three times now, which is great.

He's the first hippo that we really got a clear understanding of

his core range that we got a lot of signs for.

It was the first trap we built and he has had the most time

to have us disturbing his area and getting used to that.

After four months, time has run out for Wei.

She and the capture team must head home

but they will return.

In the meantime, Donatien and Leon

will continue to monitor the forest for signs.

CROWD CHANTS

-CROWD:

-Hippo, hippo!

Wei is back in Cote d'Ivoire

and today, she's celebrating Hippo Day with children from villages

around the forest and the rest of the Tai Hippo Project team.

It's Karim and Inza's initiative to educate the next generation

about Cote d'Ivoire's most mysterious mammal.

It's also a good excuse for a party.

These children are the future decision-makers,

they are future researchers, so it is really important for us

to drive them slowly towards nature conservation issues.

KARIM SPEAKS IN OWN LANGUAGE

Karim hopes that inspiring children to care about the hippos

and their forest home is the most effective way

to spread the word about saving the pygmy hippo's habitat.

For us, if you have your child come home and say,

"OK, Dad or Mum, we learn a lot about the pygmy hippos

"and they are disappearing."

So, we expect that this message is more strong when a child tells you

that you have to stop what you are doing.

This is our vision, that the population will start themselves

to say, "OK, we want to protect our forest

"because we know how it is important for our future."

Back in the forest, the end of the rainy season brings with it

an abundance of seasonal riches for the animals.

Western pied colobus monkeys feast on ripening bean pods,

ripping open the tough casings with their sharp canines

to reach the seeds inside.

During the wet season,

Donatien and Leon continued to bait the traps with yam,

but left the doors open

The cameras were also left up to keep tabs on any action.

And now Wei is about to see the results.

Oh, exciting!

Let's just hope the camera traps haven't let us down.

She's not disappointed.

The big male that came so close to triggering the trap

appears to be used to walking through it.

But that's not all.

A smaller, clearly female hippo is also now on the scene.

We definitely have two different individuals walking through bamboo,

so the big male and there's definitely been a female,

which is really exciting.

It raises more questions about territoriality

and the solitariness of the species.

It's a very important development.

Pygmy hippos are thought to be highly solitary,

keeping to their own distinct core ranges

and only coming together to mate.

That may explain the female's presence...

but only time will tell.

That night, Wei scours the incredibly rare footage

for any clues to the hippos' behaviour...

and finds something commonly seen in captivity,

but almost never witnessed in the wild.

There was a time we went out to check the traps

and we saw fresh spray all over the side of the exit.

So, we know one of the hippos has been and actually marked our trap,

but I think we can actually see that happening.

So, can't see it perfectly but he stops and shifts his right foot over

and turns his body angle and then you can actually...

I've actually mashed up the volume,

you can hear this, like, "chugga-chugga-chugga",

as his crazy tail is smushing urine and faeces all over the trap!

So that's really awesome, you know,

to be able to see a sign in the field

and kind of go, "I think I've actually got footage of it!"

HIPPO SPRAYS

This type of spray-marking is unique to pygmy and common hippos.

It's thought to be the way a pygmy hippo communicates its presence

within its home range.

But Wei is considering a second theory about navigation.

My hypothesis that wherever we see spray on a hippo's path,

we pretty much start looking for some kind of turn off or crossroad

or a new kind of right or left-hand turn or a bifurcation

going off in two different directions and we usually find one.

While Wei continues to put the pieces of the pygmy hippo puzzle together,

a new capture team has arrived.

Wei will work with them

but will also follow her own leads to advance the field work.

So little is known that even the smallest detail could be crucial

in building a conservation plan to save the species.

Whilst the capture team waits to see if the hippos return to the traps,

Wei is on a different mission.

Investigating a report of a hippo den.

First, she needs to check that there's no-one at home.

Pygmy hippos are thought to make their dens in river bank hollows,

like this, created by fast-flowing water as it hits a bend in the river,

under the roots of primary rainforest trees.

All right, we're all clear!

Some ecologists believe that the decline in pygmy hippo numbers

is directly related to the loss of these trees.

An improvised waterproof camera on a stick

will enable Wei to probe deep inside the interior.

Oh! Something slimy...

It's another extraordinary first.

It's believed that no-one has ever filmed

inside a pygmy hippo den before.

OK, there is definitely no hippo around.

This one goes much deeper than the other dens she's seen.

I would never have guessed the extent of the actual den.

They're always pretty small, you know,

good enough to hide a hippo in,

but this just is on a whole other level.

And there's another surprise -

strange vertical markings on the bank.

I can actually see scrape marks.

Right at the surface, you can see these marks

going down into the water,

where you've got this perfect clay wall.

The scrape marks suggest an intriguing new possibility.

We know they've got those big canines,

we've kind of always gone,

"Oh, maybe it is for fighting, maybe it's for territoriality,

"maybe it's for breeding..."

Um, maybe it's for carving out riverbanks.

It's the first time anyone's found evidence that hippos

might actually play an active role in excavating their dens.

But that's not all.

That is going in so deep.

The first entrance connects to a second.

I'm at the end of the pole.

The tunnel measures an incredible nine metres -

the length of two cars.

That is going deep this way, as well.

And three metres away from the bank, the camera pops up

in a hippo-sized air pocket.

It means, basically, that this hippo can dive under

and then resurface in an area where they can sit happily,

breathing, completely enclosed, completely safe and hidden.

And it's huge.

A single animal shouldn't need something as huge as this,

so whether they kind of use it to raise young,

especially when they're super, super little...

Whether they pair in these dens -

I mean, we don't know and considering the size of it,

now I'm kind of wondering whether that could be a possibility.

Bit by bit, Wei is unearthing new insights

into the secret life of her pygmy hippos.

But as she starts to uncover their secrets by day,

they are giving her and the capture team the slip by night.

Neither the big male, nor the female,

has been seen on camera for more than a month.

Then, while out searching for tracks,

she and Donatien stumble across something disturbing.

Oh...

Quoi?

It raises a chilling possibility

that the big male and the little female

may have fallen victim to poachers.

It's a reminder that although the Tai forest is protected,

its animals do get hunted illegally.

Karim has brought Wei to a bushmeat market,

on the border with Liberia.

While hunting forest animals is outlawed in Cote d'Ivoire,

just over the river in Liberia, it's perfectly legal.

Hunters sell their goods to traders,

who then ship the animals across the river border to this informal market.

So, you see here you have mainly monkeys.

-This one seems to be Diana monkey.

-C'est Diana?

Yes. With the teeth.

This one is a sooty mangabey. Yes, sooty mangabey.

With this one...

it's a Campbell's monkey. It's very fresh.

-Oh, wow, it's really fresh.

-Yes.

No, no, no.

Straight through the heart.

So, that's got to be less than two hours.

-Probably this morning, yes.

-Because of the rigor.

Wei is confronted with many of the species

she has seen in the rainforest being sold here as food.

Both Wei and Karim are dreading finding hippo meat.

A local monitoring team checks the market for all animals that,

like the pygmy hippo,

are on an internationally banned list of endangered species.

So, she said she started in June

and from June to now, they recorded no pygmy hippo.

If they do find an animal on the list, it gets sent back unsold,

in the hope that the no-profit message gets through.

Officially, we have a lot of law to protect the animals,

but in practice, we need more action.

Wei wants to ask a Liberian trader whether hunters target pygmy hippos.

Do you know how they try to hunt the pygmy hippopotamus?

Do people try any more, or is the animal too hard?

They will try, if they can get it.

-And there is like specialist hunters?

-Yes.

Do they make pits or do they make traps?

Some set traps, some use gun.

-Do people really like the meat...

-Yes.

-..of the pygmy hippo?

-Yes.

More than the duiker?

-More than that.

-More than le singe - monkey?

So, they will pay quite a lot of money if there's a hippo?

Yes.

There are no pygmy hippos in this market

but discovering hippo meat is popular - at least over the border -

is a reality check for Wei.

But she also understands that, for local people,

forest animals often represent their only source of protein.

The worst thing you can do is come here and start crying and yelling

and telling everyone here that their way is not OK.

I will probably go and have a little cry when I get home,

about the animals' eyes that I've looked into today.

If you imagine that each week, we have this quantity of bushmeat,

that means the pressure is very high on the forest,

high on the animals

and we don't know how long this can continue.

CHIRPING

Sadly, Wei's chances of capturing the big male or female hippo

have run out.

This morning, the capture team had to leave,

but Wei is determined to carry on as best she can.

She's back at the traps where, ironically,

there are signs of activity.

Then, at last,

she finds a hippo calling card.

Donatien!

Oh!

We've got fresh spray

in one of their really frequently sprayed spots.

We've got a really, really nice fresh poo sample,

which is the first in a really long time.

Once analysed, the poo will give Wei crucial insights

into pygmy hippo diet and genetic profile.

She can only hope that her nocturnal visitor was caught on camera.

She expects it to be the big male,

as this is his core range.

It's really impossible to tell,

especially when they're this close up to the camera.

When the female first turned up in the male's core range,

up to six months ago,

Wei wondered if it was for mating.

But her reappearance suggests it could be more significant.

We're going to go around and see if we can figure out where she went,

where she came from, what she's actually been doing

and see what's going on.

We've got brand-new fresh prints from last night,

so same hippo, same spray, this lay-on.

We might put another camera trap right here, as well.

Oh, my God. We're stepping all over signs, everywhere!

Getting caught in trees, ah... Getting too excited!

They follow the female's trail.

But the clues run out at the edge of the water.

The wily pygmy hippo has vanished,

eluding them once again.

But after weeks of seeing no hippos at all,

it's a huge relief.

It's such a shame the capture team has already left

but Wei gathers what evidence she can.

Really interesting morning.

Today is the first time they've started showing signs

back in the areas we've known about in the past.

They put up another camera to see if she returns tonight.

The next morning brings exciting news.

-Ha!

-Oh!

Ah, c'est bon!

It's the female, coming from the same direction as last night.

She kind of goes the exact opposite way

to what we've always known the male to go.

Um, so it's really interesting.

The big male has also been known to walk this trail.

It seems that the two of them are sharing the route

through this area, so it's possible they may encounter each other.

This time, the female has left a more significant trail of clues behind.

Wow, she's really going nuts, marking away!

One theory Wei has about the volume of evidence is that,

like cats, hippos may leave a trail of pheromones in the area

they feel most comfortable in -

the core of their home range.

And when they actually come back into those areas

and smell their own pheromones,

it produces an actual physiological response.

So, like a drug that alters their own biochemistry,

they kind of go, "Ahhh," and relax.

And then that forces them to become happy and mark even more.

If the female IS marking and regularly using this same area

as the big male, then it may mean that pygmy hippos

are less solitary than previously thought

and indeed might share core ranges.

Wei needs evidence that the big male is still in the area.

ANIMAL CALLS

The next morning,

she's back out to see if the big male has made an appearance.

(Please work.)

She scans the footage from the cameras

on the trail the female is using.

The first two draw a blank...

but then there's a surprise.

There we go! It's the big male!

It's good to see him again.

Let's watch that again. I haven't seen him in months.

Wei now has proof that the male and female

have been on the same trail within a day of each other.

They obviously are very, very aware that each other are there,

that there's no doubt, at all,

that they're co-existing in an overlapping habitat

without realising.

They're walking directly along the same lay-ons

and sniffing each other's poo

and coming just a day later and things like that.

You've just got to be patient and you've got to just

keep slowly fitting pieces of the puzzle together.

It's Wei's final night here.

Tomorrow, she will leave the forest and the pygmy hippos behind.

She's unearthed a host of insights

into the secret life of the pygmy hippo,

including intriguing evidence that the male and female are sharing

at least part of the same core range.

Maybe they den together and maybe they forage together

and maybe they do everything as a pair

and maybe that's actually more the norm for this species

than the other way round or they might be an anomaly.

And now Wei wants to check something else from the camera

left on inside trap one during the rainy season.

One of the hippos seen inside the trap has a notch in its left ear.

And it's exactly the same ear mark that we've seen in a hippo

from a study done in 2010.

It's not the big male, as his left ear is full,

but she's yet to check the female.

I'm just going to go through all the confirmed female shots

and just see if I can see any other markings on her.

That's her right ear...

..but that is definitely a full ear.

This means that there are not two

but THREE hippos in the same small area

and, interestingly, there could be two males.

We've never heard anything about males hanging out in the same area.

The only way to find out is to analyse the only image

where both ear and genitalia are just visible.

I'm going to have to look at it a few times

to see whether there's an ear notch or not,

but there's definitely a penis that wiggles in the corner there.

If you don't have a great image,

it actually is really hard to tell the difference

and you have to stare at it a billion times.

If that is actually an ear mark,

which I am starting to convince myself more and more of right now,

it's confirmation that the ear mark individual is in fact a male.

It raises a tantalising possibility -

two males sharing the same trail as the female.

And that would be a significant new development to our understanding

of how pygmy hippos live in the wild.

Who knows what their relationship is,

but two males existing in the same core range is huge.

And what's more, Wei now knows that this second large hippo,

first seen in 2010, has survived in this forest

for at least three years.

And that's a very hopeful sign for the future

of this pygmy hippo population.

Wei has spent six months in the forest with the team,

building a pygmy hippo case file.

In just one small area, she's uncovered some intriguing evidence.

Ha!

Her findings raise significant questions about

whether the pygmy hippo is as solitary as previously thought.

She also found clues that they may use their canines

to improve their dens.

And she's significantly increased the amount of footage

that exists of wild pygmy hippos,

the findings from which offers hope

and will now push this critical research further forward.

Wei's time here is at an end,

but she's full of confidence about the future of the Tai Hippo Project.

The biggest cool thing about this Hippo Project

in Cote d'Ivoire, specifically, is that they are Ivorians

that are super passionate,

that are also super enabled and empowered

to be in a position to really have an impact.

Everything we've learned so far will just keep helping to unravel

more and more the secrets of this really mysterious animal

and hopefully give us a better chance at helping to save them.