All language subtitles for Supercharged Otters BBC Natural World 2017 720p HDTV MVGroup EN Sub

Rarely seen, they have a
near-mythical reputation.

They have boundless energy and are
able to dive deep...

..and catch the fastest of prey.

Otters.

My name is Charlie Hamilton James,

wildlife cameraman and otter
fanatic.

I've been observing and filming
these shy but relentless animals

for the last 25 years.

For me, otters are the ultimate
predator,

perfectly bridging the gap between
two worlds -

one dry, one wet.

Yet across the planet,

their populations have hung in the
balance.

I've done what I can for their
conservation.

However, many remain in danger.

But otters are fighters...

..supercharged with a huge amount
of spirit and determination.

And now, with the help of three
orphaned cubs...

..some ground-breaking
experiments...

It's done it, that was it!

..and some incredible wild
encounters...

..I'm going to reveal their
survival secrets

and just why I think otters are
such a special group of animals.

I spent my life searching for

glimpses of these rare and elusive
creatures.

They're nervous

and fearful of humans.

But there's one place where they're
bolder than most -

Florida.

Here, clear, spring-fed rivers
provide the ideal opportunity

to film otters moving and hunting
underwater.

Something few have ever done.

If I succeed,
it'll be the perfect way

to begin a journey into their
seldom-seen world.

They know I'm here.

They're far too inquisitive not to
have noticed.

But they don't seem to mind.

There are more otters here than
anywhere I've ever been.

But, typically, they don't
keep still for long.

North American river otters can
cover over 40km a day...

..and swim for 400m without
coming up for air.

If you're going to observe otters in
the wild, you need patience...

..and a bit of luck.

I spot a telltale sign.

A trail of bubbles.

Absorbed by foraging...

..this is my chance to get close.

I want to see how it's hunting.

Something I've never achieved
before.

But I know just a flick of its tail
and it could be off in a flash.

He's so focused.

I just need to hold my nerve.

In 25 years of watching otters, I've
just got these little glimpses

occasionally of them underwater,

and here, in a single morning,

I've seen more otters underwater
than in that whole 25 years.

But what's been really interesting
is actually looking

at how they're hunting.

It made me watch him and understand
and look at the way he was doing

stuff, the way he was swimming and
fishing,

in a completely different way.

In this one incredible experience,

a completely wild otter allowed me
to come here,

hang out and watch him fish
underwater.

There's an otter right there.

HE CHORTLES

This place is so amazing.

There's just otters everywhere.
It is otter heaven.

I need to go get back in the water.

It's all very well sitting here
talking to the camera

but I'd rather be swimming with
an otter.

The experience has reminded me why

otters have captivated me for
so long.

They are incredible predators.

Energetic,

inquisitive

and versatile -

..traits they share with their
extended family.

The mustelids.

An ancient and diverse group of
carnivores

that includes weasels,

stoats, badgers and martens.

Otters can be found on nearly every
continent,

from the Arctic Circle

to the swamps of Africa.

And from desert oases to the
tempestuous seas of Patagonia.

But there are some things that unite
all otter species.

They have long, highly
flexible bodies...

..a powerful tail

and webbed feet.

Some can dive to 100 metres...

and hold their breath for over
four minutes.

But despite their amazing physical
abilities,

all over the world, otter
numbers have been in decline.

BARKING

They've been hunted for sport

and for their fur.

They've lost their food to
human greed...

..and have seen their habitat
poisoned and ruined.

But given the chance, otters are
survivors

enduring against all odds.

It's one of the reasons I've always
done what I can,

caring for otters in need.

I've even welcomed them into my
family.

Otter!

Otter!

Honey, a Eurasian otter

too dependent on humans to be
released...

..held a special place in my
heart.

And the time I spent with her only
made by love for otters stronger.

To help me reveal what I believe
sets otters apart,

I'm going to follow three male
orphan river otters

on their own story of survival.

As they grow they'll be taught

the vital skills they'll need for
a life back in the wild.

After being abandoned by their
mothers, the orphans were brought

to Wild Instincts wildlife rehab
centre.

On arrival they were weak,
defenceless

and would not have survived the
night.

Attempting to mirror their wild
diet,

centre manager Mark is giving
them chopped fish and milk formula.

But he has concerns about the
weakest orphan.

He came to us with a kind of a
bad leg.

He injured the joint on his right
rear leg,

so we're not quite sure whether
it's going to heal enough for him

to be released or not and he also
did a slight injury to the joint

right in here on this leg also

and even the good leg is not
necessarily a good leg.

So what we're going to do is try to
find a zoo for him

if he's not able
to be released back into the wild,

and if we're unable to find a zoo
then he

may have to be euthanized if we
can't find a place for him to go.

To keep any attachment to a minimum,

it's Mark's policy not to name any
of the animals in his care.

Now eight weeks old,

the cubs need to tackle an essential
survival skill -

..learning to swim.

Curiously, baby otters don't
really like water.

So Mark needs to teach them
their most important life lesson -

that water isn't something to
be afraid of.

Just like their mother would in
the wild,

Mark makes soothing calls to
reassure them.

HE WARBLES SOFTLY

OTTERS CHIRP IN RESPONSE

Each time they try to get out,

Mark plops them back in.

But their swimming lessons don't
last too long.

That's because of another
surprising quirk of otter biology.

Their coat doesn't become waterproof
until they are 12 weeks old.

Until then, being wet
could lead to hypothermia.

So surrogate mum Mark
does what he can to help out.

Normally in the wild what they
would be doing is rolling around in

the grass and the dirt

to get some of the water off
themselves,

so we can use the towels to help us
out a little bit.

Wild otter cubs face exactly
the same issue,

so the adults only take them
for short dips

to stop them getting
cold and waterlogged.

It's exactly what I saw with a
family

of giant river otters in
the Amazon.

Wow, look at that. Tiny!

That is really young. That
can't be more than six weeks old.

He's got another one.

Giant river otters are highly social

and with such young pups in the
water, the whole family helps out.

They're too small to start
swimming properly.

It's just a taster session

under the watchful eyes of
their parents and siblings.

Eventually, they'll become
accomplished enough in the water

to catch fast, wild prey.

Back in Wisconsin, otter foster
parent Mark is about to start

teaching the orphans how to fish.

But first the orphan with the bad
leg needs a little extra help.

So Mark has designed a swimming aid

and is giving him a course of
aquatherapy.

OTTER CHIRRUPS FRANTICALLY

So it looks like the little
apparatus we have put on there seems

to be accomplishing what we wanted
it to do. It keeps him afloat

and he's using his rear legs much
better than he was before without it

so hopefully this will be some good
therapy and get him on the path

to being what he needs to be.

He's obviously a little fighter.

As I arrive,

Mark's just about to give them live
fish for the first time.

MARK WARBLES

Oh, my God.

Mark adds some minnows to the
paddling pool

and hopes that hunting is more
instinctive than swimming.

How cute is that?

Go on, then.

Yesterday we were doing a
bit of diving and swimming around

and now there'll be something to
swim and dive around for

so we'll see if they have any luck
chasing around.

This one's completely at home.
It's just chased a fish.

Exactly, exactly.

Straightaway. And that's just in a
few days.

It's gone from nothing to chasing
fish underwater. Right.

He's got a fish.

He's got one.

He let it go.

He's got it, he's got it.

That's his first fish.

Isn't that amazing?

Yesterday he wasn't even
putting his head underwater

and today he caught his first
little fish.

That is amazing, isn't it? He's just
rolling around playing with it.

That's a great moment for them. Wow.

Fishing, for the orphans, appears
to be innate.

It's a good sign.

But it's something they'll need to
hone.

Do you know what?

To me, there is nothing in the world
that compares to otters.

I could sit here all day every day
and do nothing else for the rest of

my life, just hang with otters.

That's when I'm at my happiest.

'As the orphans get bigger,

'their swimming abilities will
develop, too,

'until they're as agile in the
water as the fish they hunt.'

But otters aren't just masters
of the water.

They spend up to 80% of their
lives on land.

Their ability to lead this
semiaquatic double life is what
allows them

to cope with diverse habitats and
prey.

The key to this lies in their
physiology,

and back in the UK,

I've got a furry friend to help
reveal the secrets of their success.

This is Rudy. He's an Asian
small-clawed otter...

..or short-clawed otter, because
he's got tiny little claws.

And the aim is to get a
really decent look at Rudy

and how his body works, how his
physiology works,

how he turns from an animal that can
run around on the land

to an animal that's as fast as a
fish in water,

and it gives me an excuse to just
hang out with an otter.

I think you need to go and see the
dentist, Rudy.

This camera is going to do some nice
slow motion shots

and I can track along with the otter
and then we can, you know,

we can get a good look at how it's
running.

And Rod here is going to film Rudy
swimming in close-up

and particularly in slow motion.

The thing I've always wondered,
watching them and filming them,

is how do they go from land to water
and be so brilliant at both?

And I think the reason I like what
we're doing now is because we're

going to get a really
detailed look at that and try to get

some understanding of how they
manage to do that

because very few animals can just
flip between two worlds like that.

Otters do it brilliantly.

When we slow the action
right down...

..we can see exactly what's
going on.

Otter spines are highly flexible...

..allowing Rudy to rotate
his hips...

..swing his leg forward and plant
his feet securely on the floor...

..and use his powerful tail for
balance.

And unlike most land-based
carnivores,

his front feet are well-developed

with long, dextrous fingers for
foraging and handling prey.

By bending their highly
flexible spines,

otters are able to decrease the
distance

between the shoulder and hip by
over 20%, allowing them to bound,

running up to 18mph.

But the adaptations that allows
them to live a semiaquatic life

become clearer as Rudy enters
the water.

A substance 800 times denser
than air.

As he puts his head into the
water,

his vision becomes blurry,
just like it does for us.

But an almost magical adaptation
allows him to correct this,

like an in-built pair
of swimming goggles.

At first, the density of the
water stops light rays

being brought
into sharp focus on his retina.

But Rudy has highly specialised
muscles in his iris

that squeeze the lens
so that its face bulges forward.

This refocuses the light
rays onto the back of his eye...

..giving him sharp underwater
vision.

Now that he can see clearly,

he enters the water fully and his
next trick is revealed.

Pushing his broad head
forward and rotating his hips,

he is able to straighten his body
like a torpedo.

Tucking his legs in, he
reduces the water's drag...

..only untucking them when he
wants a burst of speed.

Next he uses his flexible spine in
combination with his tail and

webbed rear feet to turn and twist
in the water.

The agility of otters blows me away.

Rudy has mastered the skills for a
semiaquatic life

but our orphans in Wisconsin
are just learning how to make

the most of their two worlds.

They're now 12 weeks of age,

old enough to move outside into an
enclosure with permanent water...

..where Mark is going to
introduce them

to some different prey.

So today we're going to do some
freshwater clams, some crayfish,

then we're also going to do some
frogs.

So we're going to start off by
introducing the clams first and,

since they really don't know what
these things are,

I'm going to cut them open for them,

so I'm going to give each one a clam

and then what we'll do is
throw some in the pond,

let them kind of figure it out,

because they'll get the taste for it

and realise that, hey, this is
something I can eat.

A wild otter's diet is broad.

They catch and eat everything
from snails to octopus.

And their inquisitive nature has led

to one species evolving an
incredible talent -

the use of tools.

Sea otters feed on
crustaceans and molluscs

but their hard exoskeleton is
notoriously tricky to get into.

So each otter has preferred tools
for accessing its favourite foods.

Be it a rock for opening clams...

..the bow of an expensive boat for
oysters...

..or an empty beer bottle for
barnacles.

By focusing on particular prey,

sea otters have a balancing effect
on the ecosystem...

..helping to keep it healthy.

Otters seem to have a relentless
curiosity.

To me it's an indicator
of just how intelligent they are.

An endearing trait, and one that
often results in play.

Essential for all otters as
they grow and develop...

..teaching them crucial life
lessons.

And it's exactly what I had
to do with Honey...

..the otter I reared at home.

HE GIGGLES

But play for her wasn't always
much fun for me.

Ow! That's my skull! Ah, get off!

This whole biting my skull thing,
Honey, I'm not a fan.

In social species, the bonds
that play solidifies

makes otter families a formidable
force.

Especially important for
giant river otters,

who regularly
face deadly predators.

With vulnerable young cubs,

this family discovered a large black
caiman in their territory.

Identifying it as a threat, they
work together,

systematically attacking it.

For three hours, the otters pinned
it down,

taking it in turns to attack
its underside and head.

Eventually, the enormous size
and power of the caiman was no match

for the family, whose bonds are so
strong that they would risk dying
for each other.

For the orphans in Wisconsin,

their best chance of a future in
the wild

will come from staying together.

Now they can get a lot
more exercise,

start doing what they need to do and
start being a lot less dependent on

us, and we can start cutting off our
human contact with them so they can

learn to be otters and not rely on
humans too much any more.

They now have their most important
piece of survival equipment -

..a warm and completely
waterproof coat.

Fur is an otter's secret weapon.

They all rely on it to keep warm.

But to understand its special
qualities,

we need to look at sea otters once
again.

They have the densest and
most luxurious fur of any animal.

It's such high quality

that trappers historically measured
all other fur against it.

It's the main reason sea otters

have been persecuted throughout
their range.

Their fur has nearly one million
hairs per square inch.

To properly appreciate the
world's furriest animal,

I've come to Monterey Bay Aquarium
in California

whose sea otter
reintroduction programme has been

instrumental in the recovery of
the population.

Beautiful. 'The aquarium's head vet,
Dr Mike Murray, has anaesthetised

'a female otter for a checkup,

'giving me a chance to take a
close look.'

Look at the size of that.
That's enormous!

She actually feels really warm.

That really, really thick fur they
have is designed to conserve heat

and she really doesn't, without
cold water, have an opportunity
to dump heat.

Her coat is so effective

that Dr Mike has to put bags of ice
on her flippers

to stop her overheating.

This is the most beautiful, silky,
soft fur you can imagine.

On the outside it's much thicker

but when you get down deep
inside it's just silk-smooth.

You can just make out the sort of
pale, white skin underneath.

It's amazing how wet it
is on the outside

and then you peel it back and it's
completely dry on the inside.

That is beautiful.

It's so soft you can barely feel it.
It's weird.

And if you look at the undercoat,

they've got these long guard
hairs, but down deep,

you look at those microscopically

and they've got all these little
scales that stick off the shaft of
the fur

and what the otter does when it
grooms is,

it just conditions the fur to get
those things to lock together

so that it becomes impenetrable
to water, essentially,

and they can get air in those
spaces,

very similar to a down jacket or
down vest that we might be wearing.

Looking at the undercoat in
microscopic detail

shows these scales lining the shaft
of each hair.

Grooming increases the volume
of air trapped in this layer...

..maximising its insulation
potential.

And in the freezing waters of
Alaska,

survival relies on good
insulation.

This mother is fluffing
up her baby's coat.

By blowing into its fur

she's filling it with air to keep
him warm.

The more trapped air, the
warmer it is.

But for it to be effective, it
needs to be kept in top condition...

..which means otters spend
hours each day grooming...

..using their flexible spine
to reach those hard-to-get spots.

We can see just how effective
their coat is with the help of some
technology.

This is a thermal camera,
so what it does,

instead of looking at a straight
image of something

as we would normally look at
through a camera,

this looks at the heat signature of
everything, so it can

tell the difference between hot and
cold and it shines up here.

You know, the yellow bits are
warmer, the purple bits are colder.

It's going to be really interesting

looking at the sea otter with
this camera,

because it'll show me which parts of
the sea otter are retaining heat

and which parts are giving off
heat.

OK, so she's right underneath me
now.

This is going to be a really nice
shot.

There she is.

So you can see, looking at that,

the bits that are really shining up
yellow

are her eyes and her mouth and nose

and just a few bits on the side
of her head,

so those are the main bits that are
losing heat. That's amazing.

What's interesting is that
the water temperature here's around

7 Celsius, and her body temperature
is around 37 Celsius.

So we're actually looking
at a 30-degree difference between

the water temperature and her body,

but we're not seeing it on the
picture.

Her body is almost the same colour
as the water.

So what that means is,

that thick fur that the otter's got

is so good at insulating the otter

that very little heat is coming
off it,

almost no difference between the
water temperature

and the temperature of the otter on
the outside of the otter

because all the heat, that 37
degrees, is being kept inside.

This highly specialised coat
is one of the reasons otters

are more capable on land than other
semiaquatic mammals...

..like sea lions.

SEA LIONS HONK

One of the differences between these
Californian sea lions and otters is

not just the fact that they've given
up their legs for flippers...

..but they're fat, great, big
fat, lummoxing things.

They're useless on land.

This is pretty much the extent of
what they can do on land,

which is climb ashore and go to
sleep.

And otters? Otters can be really
successful predators on land

and the reason is,
they don't have any blubber.

These guys use blubber to keep
themselves warm in the sea.

Otters use fur, and one inch
of fur

is the equivalent, in insulating
terms, of four inches of blubber.

The otter's fur coat not only
provides them

with superb insulation
in the water,

it also allows them to have
incredible agility on land...

..something the orphans in Wisconsin
will need to take advantage of.

At five months old, their
confidence is growing.

And their curious, intelligent
nature is starting to shine through.

So now what we can do is...

So they know you're going to feed
them, don't they?

We can toss in a fish or two.

And normally, as soon as you get a
couple in there...

Look at that,
he's straight on it. Wow.

That was so fast.

It's so lovely to come back
here and see how they've developed.

I mean, they're just huge now,
compared to what they were.

They were tiny little, helpless,
useless otters

and, back then, we gave them their
first fish

and thought, "Wow, they can catch a
fish, isn't that wonderful?"

Now you watch them and they're just
pros now.

Exactly.

If you look,

now you have a hard time telling who

the guy with the bum leg was.

He doesn't show any sign of any
problems any more.

He's just as good as the other ones
at catching fish

and just as fast and agile as
everybody else.

I'm relieved that the injury to his
back leg has recovered so well.

It's testament to Mark's skills as
a substitute mother.

He's taken the camera out now.
Look at that.

The camera is going in.

How can we get this in?

They will figure it out.

Oh, he's reframed it for us!

They're just into everything,
aren't they?

Yeah. And that's otters for you,
isn't it?

Exactly. Crazy into everything.
Everything.

Just like this, with the block.

You worry about them tipping the
block over on themselves, and, er...

Aww!

There we go. It's sunk.

THEY LAUGH

They're now swimming around, looking
at themselves underwater in it.

They're doing otter selfies.

'I just love their energy and
determination.'

These guys are clearly well on
the way to having the skills

they'll need to survive in the
wild, and that time is fast
approaching.

Their release into Wisconsin's
northern woods is only a month away.

They've got each other.
They do.

I mean, one otter, you know, that's
tricky. Three otters together?

They can learn from each other,
they are safer in numbers. Exactly.

So they should do pretty well.
They can certainly fish.

So I think we'll go on out of
here.

they're starting to get a little
bit too used to us.

We're trying to keep our contact to
a minimum

so let's get on out of here.

Cheers, guys.

Mark's intentionally keeping
contact with the orphans to
a minimum.

They need to be as independent as
possible ahead of their release.

Although they're doing well,

catching fast, wild fish
in a big open lake or flowing river

will present them with an enormous
challenge.

They'll need to bring all
their knowledge and skills together.

To reveal how otters do this, I'm
heading to Oakland Zoo in California

where I hope to film a hunt
in super-slow motion.

Here, they enrich the lives of the
otters by feeding them live prey -

goldfish.

Helping me dissect the action is
biology professor Lei Lani Stelle.

Check this out, Lei Lani.
What this will allow us to do,

while the otter's swimming, I can
track along with it and it shoots in

really decent slow motion.

We can basically slow things down
ten times.

Wow, that'll give us amazing detail
on what they're doing right at the

moment when they see their food and
are able to catch it.

He's going for it. Wow! That was
nice, wasn't it?

Look at them chasing it together.

He's having trouble
getting that one!

Look at that!

Got it.

Awesome. OK, let's have a look,
see what we've got.

Where's the play button?

That's so cool to see it in slow
motion,

so you can see all of the details of
the moving.

When we were watching it, it was so
fast it was hard to see.

It's incredibly agile, isn't it?

Yeah, you can see him doing a really
quick turn

and you can definitely
see how flexible his spine is.

So it really is, I guess,
the spine doing a load of work

and then when he needs to get the
fish, the back legs seem to come
out.

And that's how, I guess, how they
get that turn of speed.

The flexible spine combined
with its tail and webbed hind feet

allow the otter supreme agility
and speed in the water.

In the final approach,
it uses its underwater eyesight

to place the fish right in front of
its head.

That's right on the tail of
the fish, isn't it?

He kind of nudged it with his nose
first. Yeah.

It definitely seems like we're
noticing that they're feeling the

fish more than anything,

so it may be that they're detecting
it with

their whiskers first and since that
has a hard-wire

from the whiskers right to
the jaw,

they can just bite it with instinct

without having to take that time for
the brain to process the signal.

So they're not, you know, they're
not feeling it

and thinking, "Is that to my left?
Is that to my right?"

Right. It's like an instant...like
us seeing or hearing.

Yeah. Exactly, there's no delay.
And that would explain how they're

able to pick up on the fish so
quickly.

Because I would have trouble seeing
the fish and they would
already grab it.

Right. And it is incredibly fast,
isn't it?

As soon as the prey touches the
whiskers,

an incredible nervous reaction is
triggered.

The signal fired to the brain is
immediately turned into a command,

stimulating the jaw to grab.

Cutting out any
decision-making delay.

And it all happens in a fraction of
a second.

'But I've spotted something
else intriguing in the footage.'

That otter's nosing that fish and
sniffing the fish, right?

And if you look, when it first
comes up to it, it puts bubbles out.

It's got loads of bubbles around its
mouth. Right.

Because I'm convinced otters
can smell underwater.

So do you think the bubbles are
going back into the nose or into the
mouth?

I think they're going into both.
Interesting.

It's not improbable
because a lot of animals can smell

underwater, right? And it's just
a chemical cue

and as long as it's concentrated, so
it's really right close to them,

it makes sense that they would still
be able to smell it underwater.

So other animals that
can smell underwater,

do they just sniff in water or do
they use bubbles in this way?

You know, to be honest, I don't
think anyone knows.

It's thrilling to think that otters'
ability to smell underwater

could in fact be an undiscovered
survival skill.

I've long thought otters must
have this secret ability, and seeing

this has inspired me to put
my theory to the test.

I'm hoping Rudy might be able to
help me once again.

So really the only definitive way of
proving that otters can smell

underwater is to do an experiment,

so we're going to get some fake fish
and some real fish

and we're going to try and film Rudy
telling the difference

between the fake fish and real fish.

So what we've got here is a fake
piece of plastic trout.

We're going to put that on here

and we present Rudy with

two identical-looking pieces of
fish...

..to see if he can tell the
difference.

So we're going to put this
experimental block here...

..underwater.

'This relies on Rudy investigating
each piece underwater.

'Deciding which one is food and then
eating it.

'And Rod and I capturing the whole
thing on camera in slow motion.'

No interest in the fake one.

Absolutely none.

Well, come on, Rudy, do it.

It's so fast and it's so subtle,

that it's very difficult to work out
exactly what's going on.

'My camera simply isn't capable of
slowing it down enough to see the
finer details.

'But Rod's camera captures the
action 40 times slower than real
life.'

Right, Rod, did you get it?

Possibly. Really?

Yeah. It's so quick and obviously
we're slowing it down 40 times,

so until we actually see it...

So that... God, that is a close
shot. There's his head.

That's a bubble coming out of his
mouth, isn't it?

Oh, he's sucked it back in.

It's done it. No way.

That was it. Fantastic.

That's amazing.

A bubble came out of his mouth

and just as he was lifting his head,
he sucked it right back in again.

It wasn't his nose, but it was his
mouth.

He draws it back in, tasting the
fish.

That's amazing, because you can
actually see it happening perfectly.

'Rudy actively pushes a bubble onto
the surface of the fish...

'..picking up scent molecules before
he sucks it back in...

'..obtaining enough information to
determine whether it's something he
wants to eat.

'This footage helps me understand
how otters might find food in

'dark, murky waters where they can't
rely on their underwater eyesight.

'They sniff it out.

'It's amazing to think that an
animal we are so familiar with...

'..may still hold secrets from us.'

And good to think that the orphans
may have this ability too.

The cubs are six months old now and
autumn is coming.

It's time for their release.

With his parenting nearly over,
Mark has built a pen...

..which he'll leave on the shores
of an isolated lake.

'This will give the orphans
somewhere familiar to come back to

'until they're able to fend for
themselves.'

All set?

Wow, this is the moment, guys.

MARK WARBLES

Oh, look at that.

How amazing.

You can't imagine what it's like.
It's like...

MARK WARBLES

..having never been outside in
your life, isn't it?

Exactly. All these new, funny things
to explore.

They're so funny. They're just into
everything.

They run for about ten feet

and then stop and look around and
then they run.

They're just crazy.

They're checking everything out.

Checking my tripod out.

You know what's lovely is the point
where they get to the water...

..because they're suddenly going to
be otters, finally.

It's all very well looking like
an otter,

but to actually be free and be

swimming and catching fish,
that's the special bit.

So this is the accumulation of all
of our efforts coming to the end

and this is the kind of moment we've
been waiting for since we started.

And gives you a lot of satisfaction
to be able to see them out there,

swimming and doing what they're
doing...

..knowing that you had a chance to
set it right

for what went wrong in the
first place.

We'll still continue to put food
out for them

but they need to find
their independence now.

And they're
smart enough to do it.

I mean, you're still kind of mum,
aren't you?

But you're a hands-off mum.

Exactly.

Today we cut the apron
strings a little bit. Right.

'And it's obvious that the orphans
are relishing their first real taste
of freedom.'

They'll just keep expanding their
range little by little and start

checking things out and getting more
adventurous

and eventually they'll go
probably around the whole lake

and, not too much longer,
they'll probably start heading

up and down the creeks that are

coming in and out and
seeing what's there.

'In the same way a mother otter
would keep catching fish

'for her
young at this age in the wild...

'..until Mark is sure that they're
using

'all their learned and innate
skills

'he'll keep putting out food for
them.'

And what happens, do you stop
feeding them first and then they go

or do they generally just move off?

They generally just move off, so
we'll offer food for a while until

we notice the food's not
disappearing any more

and we don't see them any more.

So it's their first night alone,
now, isn't it?

Yeah, it'll be the first night alone
but I think they'll do just
fine.

They've had a lot of fun today
and I think

they're just going to find a
place to go to sleep.

I think they're going to sleep well.

I think so, too. They got a good
supper, they should be good.

'As night falls, I can't help but
worry for them.

'Although Mark's provided them with
food,

'for the first time in their lives

'they will have no one looking out
for them.'

'As soon as it's light I'm keen to
check up on the orphans.

'At first there doesn't seem to be
any sign of them.

'But then I hear some familiar
chirps.'

CHIRPING

'I'm delighted. All three are
foraging together.'

There's something about when you
see a group of otters like this,
you know,

three otters almost like this one
animal and three bodies.

They move so perfectly, so in sync
with each other.

They know where each other is
the whole time.

They know what each other is doing.

Even though sometimes they can't see
each other.

You know, this is really murky,
peaty water.

They can't see in it, but they
always know where each other is.

For Mark to have got them from
three tiny cubs to this state

and to put them in this place and
release them so quickly

and so effectively is brilliant.
I think he's done a great job.

Just looking at these guys from
this canoe,

it's just like watching a group of
wild otters

and they're doing
everything that wild otters do.

They're behaving like wild otters.

They're hunting along in the reeds
and the lilies

along the edge of the lake.

And they're foraging.
That's what otters do.

They're not always out in the middle
of the lake speeding after fish.

Most of the time they spend nosing
around in the weeds

trying to find some food, and that's
exactly what these guys are doing.

So it makes me very hopeful.

You look at them behaving like real,
wild otters and you think, well,

if you can do that within 24 hours
of being released,

I think the chances of survival for
these guys are pretty high.

'Mark has given the orphans a real
second chance at life.

'And as long as they stick together,

'harness everything their surrogate
mum has taught them...

'..alongside their own natural
instincts,

'they should be able to cope with
most things.'

I'm reassured that otters have what
it takes to survive.

History has shown this.

Where otter populations were at
record lows...

..some are now coming back.

40 years ago, the Eurasian otter was
extinct across most of the UK.

Now it's found in every county.

And the sea otter numbered just
2,000 individuals a century ago.

But with the help of protection and
reintroduction programmes

has made a population increase to
125,000.

We can't get complacent.

Across the globe otters ARE
threatened,

but where they're given the chance,
they can adapt to a changing world.

CHIRPING

And there's one place where they've
made a very surprising comeback.

Downtown Singapore.

Singapore is one of the busiest
countries in the world.

Attracting over 15 million
visitors a year,

it might not seem like a haven for
wildlife.

But despite the hustle and bustle,

and having been thought extinct
here just a few decades ago,

in 2014, smooth-coated otters moved
into the city centre.

There are now thought to be well
over 60 otters

living inside the city state.

The reason? Fresh water in
Singapore's Marina Bay has,

for the last nine years,
been highly protected.

There's next to no fishing
or pollution.

The result is a vast reservoir,
absolutely full of fish.

Perfect for otters.

And now, on a daily basis,

they demonstrate one of the
characteristics I love most.

Their close family bond.

What's really freaking me out is
that

the last time I filmed a group of
otters this big and this social

and exciting was in one of the
remotest parts of the Amazon.

That was a group of
giant otters, 15 of them.

Now I've got 13 completely wild
otters right in the middle of,

I guess, one of the most densely
populated cities on earth.

'And this family has just expanded
Singapore's population even further.

'They have four 11-week-old pups.'

'And just like the orphans in
Wisconsin,

'they, too, are on a journey of
survival.'

Otters are very sensitive animals.

They've been in trouble across the
world for a long time now.

But, if Singapore proves anything to
me, it's that they are adaptable.

'I've no doubt otters are
survivors.

'For me, it's all about their
supercharged nature.

'And I think it's this that makes me
smile every time I see one.

'And here in Singapore there are
plenty of other smiling faces.

'That's because otters ARE special
and, given a chance,

'will always make the most of what's
available to them.'

They need nice, clean water,
a decent supply of food,

and they need to be free from
persecution.

And clearly, Singapore's provided
them the perfect home.

And that basically proves to me that
these shy, nocturnal,

secretive animals that we kind of
all think otters are,

give them the right ingredients for
life...

..protect them, and they'll thrive.

And in the weeks and months
following their release,

through autumn and winter,
the orphans in Wisconsin

are also thriving.