A "weasel".
How we might describe an untrustworthy person.
It conjures up images of deceit
and betrayal.
Members of the weasel family are often portrayed as villains,
and associated with somewhat unsavoury behaviour.
We "badger" people,
"ferret out" the enemy,
"weasel" out of things.
But do they deserve this bad reputation?
Now, with ground-breaking science...
We realise, this guy's a genius.
..extraordinary behaviour...
They are essentially a super predator.
..and by following the adventures of a wild stoat family...
..we'll step into the world of weasels...
..and finally reveal their true nature.
The weasel family are also known as the mustelids.
They're one of the most varied animal groups in the world.
The 65 different species are found almost everywhere,
from the Arctic...
..to the tropics.
From the biggest - the two-metre giant river otter
that's adapted to life below the surface...
..to the smallest - the 50-gram common weasel
that gives this animal family its name.
They may look different, but they're united by a special set of skills.
It seems they can conquer anything, from the tallest trees...
..to snow-topped mountains and raging waters.
They have to survive in a world
where predators and prey outsize them.
But whether they're a stoat,
ferret, honey badger...
..weasel or a wolverine...
..they don't let anything hold them back.
Stoats and weasels are native to Britain,
and nearly a million roam the countryside.
But to get more than a glimpse of one would be exceptional,
because these animals, like all of their kind, are amongst the most
secretive on Earth.
That's what makes this corner of Yorkshire so extraordinary.
It's spring.
A young female stoat is looking for a place to start her family.
This is Bandita.
She will give us a unique chance to follow one of these elusive
animals in the wild.
Because even when she disappears, we can still see her.
Bandita lives in a garden unlike any other.
This may look like an ordinary garden, but it's designed and built
all around the lives of stoats and weasels.
We've got all sorts of different habitats.
Not only have we got the habitats, we've actually got nearly 50 cameras
covering their secret lives.
This is wildlife artist and photographer Robert Fuller.
His passion for stoat surveillance knows no bounds.
He's spent years creating a whole world for them.
So the main area of the garden is Stoat City.
Lots of dry-stone walling.
Secret tunnels leading to nesting chambers.
And this is a great area for them to run around and explore in.
Stoat City didn't seem to be big enough for the stoats.
They've even gone into our parts of the garden.
They're in the veg patch.
All over the children's climbing frame and trampoline.
Literally going everywhere.
Rob has also catered for the stoats' smaller cousin, the weasel.
The back garden's Weasel Town,
and it's all on miniature scale
because the weasels are so much smaller.
They've got log piles...
..hidden nests...
..and even ponds just for the weasels.
I enjoy watching the stoats so much, I've actually built my own hidden
tunnel underground, so I can get closer to the stoats
without disturbing them.
This stoat-and-weasel wonderland will reveal the hidden lives
of these intriguing animals.
Rob and his family spend their free time watching the latest action
streaming live throughout their house.
And now they're hoping to follow Bandita's new family.
Rob's been recording Bandita's adventures
since she was born here two years ago.
As one of eight kits, she spent her first few weeks with her siblings,
cuddled up for warmth in their nest.
WEASELS SQUEAK
As they fed from their mother's rich milk, they grew quickly...
..and after just 12 weeks were able
to live independently.
Now, two years on, Bandita is pregnant, and she's come back
to Stoat City to start her own family.
The body shape changes really significantly.
The pregnancy goes really low down between the back legs.
So she's almost engaged, really, to give birth.
Rob leaves food out for all the wild animals in his garden.
To prepare for her new arrivals, Bandita must stock up
on these offerings and find somewhere safe to nest.
Bandita is about to have the toughest few months of her life.
This first-time mother will have to draw on all
of the skills the mustelid family are famous for.
One of these is the unflinching ability to take on anything
and everything around them.
The boldest of the family takes that to extremes.
The honey badger.
Living in the African bush, they cause havoc wherever they go.
GROWLING
Daring and dangerous, they'll face up to lions, hyenas...
..and even venomous snakes.
But they don't just have brawn.
They also have surprisingly large brains for their size.
It's even thought that honey badgers might be some of the most
intelligent animals on the planet.
But just how clever are they?
South Africa, home to the Moholoholo Wildlife Rehabilitation Centre,
and a remarkable rescued honey badger
called Stoffel.
He became notorious for his ingenious escape antics.
You really want to know what Stoffel's like?
You want to bring back memories and nightmares?
Brian Jones runs the centre and couldn't believe
the extraordinary lengths Stoffel would go to.
He was escaping through electric fences.
He opened doors and latches.
Then we realise, this guy's a genius.
He dug these rocks up and rolled
them with his back feet and he escaped,
so we had to take all the rocks out.
It had been raining and he made
some mud balls and he rolled these mud balls
to the corner of the wall and got out with the mud balls.
It's just phenomenal, his escaping antics.
This certainly suggests brain power,
but how does it stand up, scientifically speaking?
Dr Natalia Borrego studies animal intelligence.
Honey badgers are really cool.
They have these really complex ecological lives,
these very broad diets.
So they need to climb, they need to dig.
They do these behaviours that
indicates a high level of intelligence,
but we haven't actually tested that yet.
Stoffel's more obliging son Stompy...
..and another rescued honey badger, Julius,
are taking on the challenge.
This is a specially designed puzzle.
Inside the box will be food covered in honey - their favourite treat.
To open the door, they must lift the wooden bar.
This tests their problem-solving skills.
It might look simple, but this
is something they would never see in the wild.
So they must be innovative and use their imagination
to figure this out.
He's trying a bit of everything.
Yeah. I know leopard or hyenas, they bite and bite,
they will bash it, but didn't have the brains to actually think,
"There's a gadget holding this closed -
"I've got to move it out the way."
There you go. There you go. You've got it.
Good for you.
Well, I'll be blowed. He's actually done it. Yeah.
Well done, sir.
Both Julius and Stompy solved this first challenge.
But what happens when it becomes more complicated?
A lot of animals have difficulty, once they figure out how to achieve
a goal in one way, they get kind of stuck on that solution.
So we're going to see if honey badgers
are able to change their thinking
and not get stuck on that bar solution.
This second challenge tests how adaptable their brains can be.
There's a clear container inside that the food will be in,
but it's out of reach of the honey badger.
So they have to figure out to pull the string to get the food.
Do you think they'll be able to solve this one, as well?
My experience with it over the years is there's nothing he wouldn't
really solve, unless it's a lock and a key.
In the wild, honey badgers eat up to 60 different species.
To hunt this range of food, they have to think flexibly.
He's worked that out!
Isn't that wonderful, hey?
You can't help but love these things.
Doesn't matter what they do to you!
So far, the honey badgers have shown problem-solving
skills and adaptability.
But in the third and final test,
can they do something that would mark
them as one of the most intelligent animals on the planet -
use tools?
We've hung the box from a tree,
so the honey badger can't reach it from the top.
That can't reach it from the bottom.
The only way they can reach it is by dragging either a tyre
or their cage under it, so that they can then step up
and reach the food that is inside.
If, in fact, honey badgers can use tools, this puts them
up there with some of the smartest animals in the animal kingdom,
like chimpanzees or elephants.
So it would be really exciting.
Every single one has had that ability to escape, to take an object
to the side of the wall and climb out.
So, definitely, the potential is there.
So he seems to be just jumping
and trying to get to the box, but not making
that connection that he needs to bring the crate or the tyre over.
He really wants it
but he just can't seem to figure out how to get to it.
You see, he knows there's something there.
Mmm, he's looking at it...
He pushed his crate closer to the box
so that he could then climb on top of the crate
and get to the box, which indicates tool use,
and is really exciting.
Stunning.
That is pretty cool, I must say.
Giving them this puzzle box is confirming what we've long
suspected - that honey badgers are very good at solving problems,
that they're very exploratory and adaptable.
From what we've seen, they're up there with the top innovators
in the animal kingdom.
It's this intelligence - often misread as calculated and cunning -
that gives these animals an edge in the wild.
Back in Stoat City, it's May.
Bandita has given birth, but her kits have remained hidden...
..until one morning, when she gave Rob
the surprise of his life.
I'll never forget the day when we first got the footage
of the kits emerging.
One by one, the kits came out and then we realised
there was four kits.
Incredible things, because they were
actually a really strange colour.
They were a white, mottled-y colour.
This is really rare.
There's very few records of this right the way across the world.
So we're absolutely delighted
that we've got extra special stoat kits to watch.
Some stoats turn white - or ermine - in the winter
to camouflage themselves against the snow.
These kits were born in a cold spell, which could be the cause
of their unusual colour.
But their first outing doesn't go to plan.
Inexperienced mum Bandita quickly loses control of her kits.
One falls over the edge of a wall.
Followed by another.
Bandita appears to panic...
..and instinctively moves her kits away from this danger.
She leaves Stoat City, and Rob
spots her running into an elm tree down the valley.
For now, the kits seem OK.
But this move has unwittingly led her into further peril.
This nest site could jeopardise the safety
of her vulnerable youngsters.
She's got problems here.
She's next to the road.
And this is also the favourite tree for a family of tawny owls.
The kits are in real danger here of predation.
Not so much her - she's quite feisty -
but the little kits walking around, they're quite pale,
and they really stand out in the dark.
This is the road just here.
So instead of running up the dale side, which is the sensible thing
to do, she actually goes out onto the road,
which is really dangerous.
To hunt in her usual territory, Bandita risks everything,
travelling 100 metres along the road.
I've watched her coming up the hill, and a van comes down,
and you're just like, "Oh!"
It's just... You're just hoping she spots it.
You know, hoping they're all going to be OK.
Will Bandita be able to keep her kits safe
in this perilous location?
Moving kits from nest to nest is one of the mustelids' survival
strategies, but it can involve risks.
During the journey, kits can become separated from their mum.
Weasels - the smallest of all mustelids,
and a close relative of the stoat -
are particularly vulnerable.
A baby weasel that was lost during a nest move
has been spotted and rescued.
She's now in Rob's care.
This is quite incredible here.
We've got a tiny little female.
This is about three weeks old.
Tiny little tail, which obviously tells us it's a weasel
rather than a stoat.
At this stage, we call them fingerlings, because they are
literally the size of your finger.
By following this orphaned weasel, we can see how she grows up
to be a tiny but mighty predator.
Rob names the weasel Twiz.
The actual name weasel - "weasel out of a situation" -
it has such negative connotations.
But when you see such a sweet little baby weasel like this,
it's hard to imagine why you had...negative, in any way.
They're absolutely stunning little mammals.
A week has passed.
In these early days, weight gain is vital.
And last week, Twiz weighed just 12g.
These tiny animals have an extremely
high metabolism and have to feed every few hours.
That's incredible - she's actually 30g now,
so she's put on more than double her weight in one week.
Absolutely brilliant.
Her fur's grown, her eyes are just about to open any day now.
Her feet are getting more useful.
She's able to move around a lot more.
Teeth are coming through now, and she's eating meat.
So she's on high-protein diet
so she's going to grow really quickly now.
Even though her eyes are still closed, her senses
are absolutely astonishing.
She's able to use her sense of smell and find the food.
This incredible smelling ability is one of this animal family's
most valued skills.
And one uses this to its fullest potential -
the wolverine.
They're found across the Arctic regions of the northern hemisphere.
And every part of them was built for the cold.
They travel up to 20 miles a day, foraging across the wilderness.
Even sniffing out prey from deep under the snow.
But how are they able to do this?
Dr Deborah Bird from the University of California studies
how carnivores smell.
She believes that an animal's scenting capacity is linked
to a structure in their skull known as the cribriform plate.
The cribriform plate is an imprint of an animal's sense of smell.
So the more nerves dedicated to smell,
the larger the cribriform plate.
The cribriform plate is located between the nasal cavity
and the brain.
It's a bony, sieve-like structure with holes for nerve fibres
to pass through.
These nerve fibres carry scent signals from the air to the brain.
The bigger the cribriform plate and the bigger the holes,
the more scent information can travel to the brain.
So with a wolverine, it's quite large for its body size.
That suggests that the wolverine has a really keen sense of smell.
That's a hypothesis, and it needs to be tested by looking
at its behaviour.
For the first time, the wolverine's
sense of smell will be put to the test.
Sweden.
Nordens Ark Zoo on the west coast
is home to six native wolverines.
Dr Marta Gasci has studied the smelling capabilities of dogs
and wolves, and now she's turned her attention to wolverines.
This is a rather simple experiment.
There are plastic pots under all the ceramic pots,
but only one is baited.
Meat is placed in just one of the four plastic pots
and the wolverine has to sniff out where it is.
The test has three levels of difficulty.
In the first, the plastic pots have no lid on them.
In the second level, the pots have three holes in the lid.
And finally, in the last level, there is just one small hole
for the scent of the meat to escape.
With their relatively large cribriform plates,
this first level with no lid should be straightforward
for the wolverines.
Within minutes, they can locate the meat in the open pot.
OK, let's check that one.
The next challenge is the pot with three holes in the lid.
Once again, the wolverines manage to locate the food
in less than a minute in almost every trial.
On the experiment's third and final level, the lid of the plastic pot
has just one single hole.
This task is so difficult that it triggers the wolverines
to start using a deep blowing technique.
WOLVERINE BLOWS OUT
They breathe air in through their mouth and force it out
through their nose towards the meat.
This warms and disturbs the odour particles, causing the smell
to become stronger.
Even though barely any scent is escaping from the pot,
the wolverines can now locate the food.
You can imagine how difficult it could be to smell out the meat
through this tiny hole.
And that's what the wolverines did.
The wolverine's sense of smell has never been tested
like this before.
The results suggest that a large cribriform plate could indeed
be behind an animal's heightened scenting ability.
This ability means that wolverines and other mustelids
can find the food they need to survive, wherever it is.
It's key to their success in the wild.
Orphaned weasel Twiz is now five weeks old.
Her eyes have opened, her hearing is becoming more acute,
and she's much more active.
In the wild, Twiz would be playing with the rest of her litter.
So Rob has to take over this role.
Play is how a weasel would learn how to fight and to hunt.
They use all four limbs to grip the prey items,
deliver a real powerful bite, then, to the back of the neck,
but very gentle at this stage.
She's only small still, so it's fabulous to see
that she's got this instinct in her already.
TWIZ CHITTERS
The little chittering, this is like a contact call.
I've heard this in the wild with wild weasels lots of times,
and it's... To me, it's one of the most
beautiful sounds that there actually is.
TWIZ CHITTERS
Twiz must start strengthening her muscles, to improve her agility.
And this needs to be done indoors.
We're going to test her strength, agility, in a safe environment.
Rob wants to see if Twiz is brave enough to explore,
but also cautious enough to hide from any danger.
Got to be always close to cover,
because they're vulnerable from attack from other predators.
She's heading for cover when she's really unsure,
which is a great sign, because she needs to be
absolutely on the ball when she's out in the wild.
At this age, wild weasel kits would go on day trips
with their mum, who would show them how to hunt prey...
..and Rob's got just the thing to help Twiz.
It'll be an easy target. ROB CHUCKLES
In a matter of weeks, they'll actually be independent
and hunting for themselves.
Weasels eat anything from birds to voles,
so they need to climb and tunnel.
She's just coming back for a little bit of reassurance.
That's what they'll be doing in the wild, going back to their mother,
and she'll go off again, adventuring.
She's showing great signs.
Yeah, it's great to see.
Stoats and weasels are at their most vulnerable when they're young.
Their early weeks are full of challenges
and important life lessons.
BIRDS CHIRP
It's now June.
Bandita has brought all four kits back to Stoat City...
..and they've made their home in one of Rob's specially rigged nests.
The kits are nine weeks old,
but, worryingly, one clearly isn't thriving.
Having a runt in the litter is common.
If they are born smaller, they struggle to compete
with their bigger and stronger siblings for food...
..and sometimes the struggle proves too much.
Unfortunately, it passed away.
It's a difficult thing to watch. It was quite a sad day, really,
that you realise we've lost one of these really special little stoats.
Despite this sad loss, Bandita still has three kits to care for.
Their appetites are enormous.
She has to feed them half of their body weight every day.
It's a difficult job
and it's about to get even harder
as Stoat City is facing an invasion.
Rats!
The archenemy of stoats.
Not only do they steal food from Bandita,
but a big, dangerous male has been trying to get into her nest.
Rob has an idea to make sure there'll be enough food for all.
We need to put some food where rats cannot get.
So we've chosen a children's climbing frame
and put a high wire four metres up.
So this is a place where the stoats can get to,
but the rats will really struggle to get right up here.
Rats will climb trees, rats will go into birds' nests,
but this is going to be too much for the average rat, going up there.
We've got the whole area rigged with cameras, as well.
So we'll be able to see
over the next couple of days how she gets on.
As night falls, Bandita appears,
and her exceptional sense of smell
draws her straight to the climbing frame.
Her tail is half the length of her body
and helps her keep balance when up high.
Bandita leaps vast distances -
over ten times her body length -
bravely pushing herself to the limit to get food back to her kits.
For such a small animal,
this jumping ability is astounding.
Once again, Bandita has overcome adversity to provide for her family.
The saying "to weasel out of something"
owes its origin to this animal family's extraordinary agility.
Many of the mustelids are known for their acrobatics.
North America.
Home to one of the most arboreal and agile mustelids of all -
the American pine marten.
They're built entirely for life in the trees.
Their long, bushy tail keeps them balanced
when jumping from branch to branch...
..and their razor-sharp claws grip tightly into the bark of trees.
They have to hunt up here, too -
moving swiftly through the branches in pursuit of their prey.
In the springtime, they raid birds' nest for eggs.
An easy job with this stationary target.
But for the rest of the year,
their prey is on the move.
Their claws are their secret weapon.
Not only do they help them latch on to tree trunks,
but they can also partially retract,
so the marten can move easily on the ground
when an appetising meal turns up.
Mustelids are so versatile
that they can use their agility in many environments.
One species is particularly adept at manoeuvres below the ground.
The ferret.
They were domesticated from the European polecat
over 2,000 years ago.
In the wild, these animals hunt in tight and twisty burrows
and their entire body can bend 180 degrees -
both vertically and horizontally.
But how were they able to do this?
Ohio, in the USA.
Dr Angela Horner is the world's leading expert in ferret locomotion.
Ferrets are really neat.
It's almost as though you have an animal in liquid form.
They have a really well-adapted body design
to move rapidly through a tunnel and change direction quickly.
And it has to be small enough to enter a tunnel,
but large and powerful enough to overpower something
when it encounters that in the tunnel.
This unique body shape is crucial for an animal
that spends 90% of its time underground,
but being subterranean makes studying ferrets hard.
This Perspex tunnel will allow Angela to see
how their bodies transform as they enter a burrow.
So what I'm looking at here is a special set-up
designed to let me see what's happening during the transition
from above-ground conditions to below-ground conditions.
We haven't really seen yet how this is happening
from the animal's perspective,
so I'm really excited to try this out.
By filming the ferret in slow motion,
Angela can see exactly what the ferret is doing.
When they're moving around above ground,
they have an arched-back posture.
And as they enter a tunnel,
they seamlessly lower that posture in their back
until their spine is stretched out.
This flexibility in their spine
is due to a unique set of back vertebrae.
In other animals, protrusions, known as "processes",
on each segment of the spine, stop it from moving too far.
In ferrets, these processes are thinner,
creating flexibility and movement.
So their spine can stretch out when they go underground,
making their body 30% longer.
This footage shows how easily the ferrets can transition
from above to below ground.
But these animals are predators.
So what impact does this manoeuvre have on the ferret's speed?
The black-and-white card helps Angela determine
how fast the ferrets are travelling across a set distance.
When the footage is lined up,
it reveals something completely unexpected.
The ferret barely loses any speed at all when running underground.
Their shorter-than-average limbs allow them to still be able to move
very well and they aren't restricted
in the limb movement in that position.
In most carnivores,
the legs and body are about the same length.
But in burrowing mustelids, like the ferret,
their legs are only half the length of their body.
This means they can run in enclosed spaces
without tripping over their own limbs.
Their limbs have to
become more crouched
to get into that position.
But they can manage it just fine.
In fact, they do it so well
that they barely decrease speed
when they're making that transition
from above ground to underground,
and that's incredible.
The ability to shift so seamlessly between these environments
is just one of the remarkable ways
that mustelids have refined their agility to catch prey.
Back at Rob's house,
Bandita's kits are now ten weeks old.
So far, most of their days have been spent safely hidden away.
But now they're ready for a trip into Stoat City.
We've named them Snap, Crackle and Pop.
Snap's the one, he seems to be a little bit more
adventurous on his own.
Pop's the one with the little panda-looking eyes.
He's a little bit of a mummy's boy. He's always close to Bandita.
Crackle's the female and she's substantially smaller,
but she's got some real attitude about her.
She really holds her own against the boys, fighting, rolling, playing.
Bandita will need to watch over the kits
every moment of this day trip.
It's a big garden and they could get lost.
So to keep them close,
she makes a special chitter contact call.
BANDITA CHITTERS
It's time for a tour of her territory.
She shows them the key places they can sleep and hunt.
Over the next few weeks, they move on to the next lesson.
Bandita needs to teach them
how to hone their chasing and fighting skills.
This is really important
because this is teaching the kits how to hunt
and they will be hunting dangerous animals.
And it looks like these lessons are also lots of fun!
The trampoline's a great area for the stoats.
They're loving being on there.
So they're learning new tricks on their pouncing,
and they also just love the texture of the trampoline.
They climb on and they just slide on,
pulling themselves along with their front legs.
After six weeks of intensive training,
Bandita's biggest kit, Snap, is ready to go
on a special hunting mission.
But Rob's garden is also home to other predators.
They compete with the stoats for food,
but they could also prey on the young kits.
As darkness falls,
owls come out to hunt.
Bandita and Snap need to fight for their turf.
SCREECHING AND CHITTERING
These owls are three times their size,
so the feisty stoats are punching well above their weight.
Their courage and tenacity means Bandita and Snap are victorious.
They've secured the territory and food for the family.
To be truly independent, the kits have one more test.
They need to hunt their own food.
Fortunately, all stoats have a secret weapon -
an exceptionally strong killing bite.
They can take down a rabbit - an animal five times their size -
with one deadly strike.
But the strongest bite, pound for pound,
is thought to come from the stoat's cousin, the weasel.
At only 15 centimetres long -
just over the length of a £5 note -
they are the smallest carnivore on Earth.
So could they really have the most powerful bite?
North Carolina, on America's East Coast.
Dr Adam Hartstone-Rose and his team
are studying bite force in an entirely new way.
The way that we get data from a specimen is we'll remove
each of the muscles that are responsible for closing the jaws,
and by analysing those muscle fibres,
we can tell whether a muscle is more adapted for stretch and speed
or whether it's more adapted for producing great strength.
So what determines an animal's biting ability?
Bite force is actually a combination of three factors.
The first is the length of the jaws
and then the second factor is the amount of force
that the muscles can actually put into closing the jaws.
And the third factor is the placement of the teeth
along those jaws.
The weasel has a relatively short jaw on a relatively long skull.
The jaw is about 50% of the length of the skull,
and that means that it's able to more efficiently transmit the force
into a higher bite force.
If an animal has a long jaw,
the force it produces is lost over the distance it has to travel.
When an animal has a short jaw,
the force has less distance to travel and to decrease.
The shorter the jaw,
the greater the force.
This is why, in a nut cracker,
the nut is placed as close to the joint as possible -
so that the maximum force goes directly into the nut
and is not dispersed elsewhere.
But the weasel also has another unique adaptation.
For its body size, the weasel has a really long skull
and that leaves a really large surface area
for the attachment of one of the muscles that closes the jaw.
And that means that it can produce a lot of bite force
for such a little guy.
Bigger muscles - or bigger springs -
have a huge impact on the damage a bite can do.
The main muscle which closes the jaw is known as the temporal muscle.
It travels from the top of the skull,
right down to the jaws themselves.
But there's one final factor in the weasel's killer bite.
For such a small animal, it actually has really amazing teeth.
So the canine tooth is really long and sharp and pointy,
which means that the bite force that is transmitted
into these killing teeth is transmitted very powerfully.
As a force disperses across a surface,
the pressure at each individual point is shared around.
Concentrate all that same force
into a smaller area, and the pressure becomes much greater.
This is why the weasels' pointy teeth give them such an edge.
All their muscle force is focused into a razor-sharp point.
Combining all three parts -
the shorter jaws, creating better leverage,
the larger springs, representing more powerful muscles,
and the sharp teeth, to really concentrate all of that force -
this really creates the ultimate bite.
And when the weasel's dissection data is analysed,
the results are extraordinary.
It has relatively higher bite force than the lion and the tiger,
pound for pound. Higher than any of the bears -
higher than a brown bear or a polar bear.
It's quite surprising.
They're frightening little guys for their body size.
That's quite impressive.
Adam can demonstrate just how impressive this is
for such a tiny creature.
If we were to take this weasel
and scale it up to the body size of this huge tiger,
then what we would find is that the skull
would actually be 40% longer than the tiger's skull and 20% wider.
Their muscles would be much bigger,
and their teeth longer and sharper.
And so, that would really make this, essentially, a super predator.
Imagine what it would be like
to be chased by one of these fearsome predators.
WEASEL SQUEAKS
This amazing bite force is what makes weasels
one of the most unparalleled predators on the planet.
In Weasel Town, rescued weasel Twiz
is showing all the signs that she, too, could be a successful hunter.
She's now ready to move into an outdoor enclosure
and become more independent.
It's really crucial for her that we get her thinking she's a weasel
rather than part of a human family.
TWIZ CHITTERS
This will be one of the last times I handle her.
Fabulous little animal - real character.
I'm going to miss her, you know?
It's going to be difficult to let her go.
She looks quite happy,
so I think we just leave her now to explore her new area.
After a few weeks of independence,
Rob feels Twiz is ready for the next milestone.
She's a excellent climber, she tunnels,
so I think she's really at the stage now
where she's ready to be released into the wild.
DOOR CLACKS
There we go. The door's open.
So we'll wait and see.
Twiz takes some cautious steps towards freedom.
She's going really slowly,
investigating everywhere, sniffing.
For now at least, she joins the other weasels of Weasel Town.
I've done my best to teach Twiz everything I can
to become a wild weasel
and it's really exciting to see how she's getting on.
Across the garden, in Stoat City,
Bandita's kits are also ready to leave home.
Bandita has done whatever it took to keep her kits safe.
This first-time mother has nurtured them
and fought to keep them fed.
She's taught them everything she knows...
..and they've had some fun along the way.
Rob's garden has revealed a unique insight into their lives,
but more than anything,
it's been a safe haven for this family to thrive.
I'm really proud of Bandita.
She's raised these three really strong, independent stoats,
ready to go forth and find new territories.
As the kits reach adulthood,
they will seek out new areas to live alone.
But Rob hopes that won't be the end of following their story.
I obviously hope to see them again
and maybe even, like Bandita, get one of them back here breeding.
That would be just the icing on the cake for me.
There's so much more to the weasel family
than their reputation would suggest.
Their cunning is merely proof of their impressive intelligence.
Their sneaky manoeuvres are a sign of their remarkable agility.
And their savage nature is a nod to their exceptional bite.
Feisty and fearless,
they are some of the most accomplished predators
on the planet.