Original subtitles

Narrator: Why is this lone dolphin

Making weird patterns in the mud?

That probably isn't just random.

Narrator: How come a porcupine is walking right on top

Of this deadly predator?

This is one seriously sneaky snake.

Narrator: And what on earth are these two lynx shouting about?

[ lynxes shouting ]

Nature is awe-inspiring,

But sometimes, it just doesn't make sense.

Man: I have never seen anything like this.

Our team of experts investigate the weirdest animal behavior...

That's amazing.

...And the most unexpected events...

What is causing that? ...Ever caught on camera.

My, god.

These are...

-- Captions by vitac -- www.Vitac.Com

Captions paid for by discovery communications

July 2018, st. Petersburg, florida --

Outdoor enthusiast michael mccarthy is watching

A lone dolphin from his see-through canoe.

Then it starts doing something strange,

So michael launches his drone

To capture a bird's-eye view of what's going on.

It reveals something interesting.

As it goes, it's creating this sort of cloud of muddiness

That is in a big circle.

Narrator: The question is, what is this lone dolphin doing?

Riskin: Anytime you see a weird behavior,

There's a very good chance that it's just play.

We know that dolphins play a lot of the time,

Both in groups and by themselves.

Aryee: Sometimes you see dolphins

Picking up bits of seaweed

And just passing it around from one dolphin to another.

Daly: Play behavior could be anything from bow riding,

Leaping out of the water,

And even playing with the sand.

Narrator: Could this dolphin be messing around

In the mud just for fun?

Where dolphins have been seen playing in the mud before,

They've been using their nose in the mud.

Narrator: They use sonar to scan the bottom

And locate hidden objects,

But this dolphin appears to be using its tail

As the mud trail appears behind it.

It doesn't look like the classic play behavior

That we see in dolphins.

Narrator: Okay, so not play.

What other reason could the dolphin

Have for dragging its tail in the mud?

Riskin: There are lots of marine mammals

That will clean themselves off by rubbing along the bottom.

Bowhead whales do this.

Killer whales do this.

It's thought to help remove parasites and shed their skin.

Narrator: But some whales have more extreme beauty regimens.

August 2018, monterey bay, california --

This lady got quite a fright.

Woman: [ screams ] oh, my god.

Come on. Get up. Get up.

That's it. We need to leave.

Narrator: A humpback whale was scraping itself clean

On the side of her boat.

Woman: This is, like, barnacles, like, whale barnacles.

Narrator: Barnacles are small crustaceans

That will attach to pretty much anything, including whales.

These plankton-eating freeloaders can cause friction

And slow the whales down.

They're probably a bit itchy, too,

Which is perhaps why this whale wanted to be rid of them.

Woman: [ screams ] oh, my god.

Narrator: Dolphins don't usually have barnacles

Because of their speedy lifestyle,

But they still need to keep clean.

Dolphins have very flaky and loose skin.

So it is a possibility that this dolphin

Is trying to use the sediment

At the bottom of the water to clean its body.

Narrator: Sounds good,

But there's a problem with this theory.

Uh...

What is the problem?

Daly: For dolphins to shed their flaky skin,

They don't need to rub themselves up

Against rocks or sand.

Narrator: Instead, dolphins shed their skin

All the time as they swim.

So cleaning is a dead-end.

Are there any clues we might have overlooked?

Daly: In this clip, you can see that the dolphin

Is moving around at the surface of the water in circles.

And that probably isn't just random.

Narrator: But why would a dolphin deliberately stir up mud

In a circle?

The solution to this comes from paying attention

To what happens after the circle is drawn,

Because once the mud is in place,

There are a whole bunch of fish that react to it.

Humpback whales will go around in a spiral,

And they'll start releasing bubbles from their blowholes.

These bubbles basically make a net, a bubble net,

And it traps the fish inside, and they gorge on those fish.

♪

Narrator: It turns out that bottlenose dolphins

In florida have created a unique version

Of this technique using mud,

And it's very effective.

The fish in a frenzy get confused

And start trying to leap out of this,

What they see as a solid wall, this mud ring.

The dolphins then snap up these fish.

Riskin: What this dolphin is doing is a hunting technique

Called corralling, getting a whole bunch of fish

Into a tight cluster and taking advantage of it.

Aryee: This is the first time a dolphin has been filmed

Doing it by itself.

This lone dolphin has learned

This behavior from its counterparts

And has been able to mud ring by itself.

Narrator: It hasn't snapped up any fish, though,

So it hasn't quite nailed the technique.

Despite the great efforts of this single dolphin,

Obviously, he's still learning.

Narrator: This extraordinary footage has captured not play time

Or a beauty regime,

But a solo and unsuccessful twist on a hunting technique.

♪

January 2015, dinokeng game reserve, south africa --

Researchers set up cctv cameras to film puff adders in the wild.

They were not prepared for what they captured.

Burke: What you see is a puff adder in the center frame.

This porcupine goes past.

And it actually steps on the snake.

What's really, really extraordinary about this footage

Is puff adders are incredibly venomous.

Narrator: But the porcupine crosses without even noticing it,

And another clip featuring an animal

That eats puff adders for breakfast is even weirder.

This cat-like animal, called a genet, walks right past

This free meal.

So how is the puff adder going undetected?

Burke: Some animals use a very simple strategy of camouflage.

They just hide in plain sight.

That's why you have these beautiful kind of chevron-like

Patterns on the snake.

Narrator: Ash miller at wits university, south africa,

Has been studying puff adder behavior.

When they're lying up underneath a bush or in a grass clump,

You will never see them unless they're moving,

So when a predator approaches a puff adder,

It's best form of defense is actually just to remain hidden.

Narrator: But the puff adder is the third-most venomous snake

In africa, after the black mamba

And spitting cobra,

So why put on the disappearing act?

People often mistake the idea

That a venomous animal is well-armed.

They're not. The venom is intended for their prey.

Aryee: Puff adders are ambush predators,

Which means that they lie in wait for their prey

To come by at just the right time

And then, boom, unleash that venomous bite.

And what that means is the snake is sitting in one spot

For potentially days if not weeks at a time,

Which makes it really vulnerable to predators itself.

Narrator: But camouflage doesn't always work.

Relying on camouflage is great if you're trying

To avoid predation by animals that rely on visual cues,

But what about sense of smell?

Narrator: The cape porcupine and the genet in the cctv

Footage are nocturnal,

Relying more on smell than sight to find a meal.

The question is, why aren't these animals

Smelling this snake?

Narrator: In south africa, a genet and a cape porcupine

Are oblivious to puff adders,

Even when the snake is right under their noses.

These nocturnal animals rely on their sense of smell

To find food,

So how are puff adders going undetected?

Could they somehow be disguising their scent?

We see animals covering or masking their own scent

With the scent of other animals.

Narrator: A rock squirrel will chew up rattlesnake skin

And lick its fur.

Burke: It does this to mask its own scent

With the scent of a rattlesnake,

Which I imagine would be quite an advantage

If it's trying to not get eaten by things.

Narrator: So are puff adders undetectable

Because they're masking their scent?

Watching this footage, though,

It's clear that these animals going past this puff adder

Are simply not smelling anything at all.

You'd expect to see some sort of reaction.

♪

Narrator: We know animals can't see the camouflaged snake,

But the question remains why keen noses can't smell it.

Ash miller focuses her phd research

Around this very mystery.

To put the snake to the test under scientific conditions,

She's recruited a local snake expert.

Enter trouble, a sniffer meerkat.

♪

Meerkats are real snake specialists.

They've evolved to find snakes in the wild.

Narrator: That's because meerkats are on the snake's menu.

When they catch a whiff of a snake, they band together

And mob the intruder until it slinks away,

So surely they can detect puff adders.

Ash prepares a lineup of test tubes for the challenge.

Each contains a cloth with a specific smell.

Some of them have got blank cloths in,

Which are just clean cloths.

One of them has a control scent in,

Which is just the smell of the clean tub,

And then one of them has a puff adder scent in.

Narrator: This target scent is collected by adding

A live puff adder to the clean tub

And then taking a cloth which has touched the snake.

Ash gives the meerkat a whiff of a puff adder cloth.

Can trouble find the snake based on its scent alone?

Narrator: He's hungry for the task...

Miller: Oh, good boy.

...And the mealworm treats.

So you see, trouble has just found puff adder,

Which is fantastic,

But if he also indicates the control,

He's telling us he can't tell them apart.

Narrator: Remember, the control is just the smell

Of the empty tub.

Miller: Oh, and he's just hit the control.

Narrator: Sorry, trouble, no treat this time.

Now, our little meerkat was really good

At detecting the smell of other snakes,

But when it came to the puff adder sample,

Trouble was in deep trouble.

Narrator: He couldn't smell the difference between a cloth

From the empty tub and a cloth rubbed on the snake.

The sneaky puff adder evades detection once again.

Okay, so here's a crazy idea --

Maybe this snake has no smell at all.

Okay, we need a serious nose.

[ elephant trumpets ]

Narrator: In south africa, something weird is happening.

A snake is going undetected,

Even by animals with a great sense of smell.

Is it possible that the puff adder

Simply has no detectable scent?

Only one way to find out.

We need the ultimate nose.

Miller: What about an animal who has probably the best sense

Of smell in the animal kingdom, the african elephant?

They have over 2,000 olfactory receptor genes,

Which is incredibly high.

Narrator: Dogs are famous for their sniffing abilities,

Yet they only have 800 of these smelling genes,

Which means elephant noses are far superior.

So can they find puff adder?

Narrator: Ash scales up her experiment

To mammoth proportions

Using elephants trained in scent detection.

At first, it seemed that the elephants could detect

The smell of the puff adders.

-Good boy. -Good boy.

Narrator: The elephants were finding the right canister

And ignoring the control every time.

But it turns out that the elephants

Were being a bit cheeky.

Miller: When you paid proper attention to the actual footage

That we've been collecting during these trials,

We realized that these guys were cheating.

Narrator: After the elephants were rewarded

For finding the puff adder scent...

Miller: Good boy.

...They were pulling a sneaky maneuver.

Aryee: The elephants would mark that particular canister

With the scent or smell of its own trunk,

So even though the canisters might have been moved around,

The elephant was able to identify

Where the canister was by detecting its own smell.

Narrator: It seems the elephants

Were stumbling across the right canister

And turning that into a winning streak,

But now that ash uses fresh canisters in each run,

It turns out that, like trouble the meerkat,

Elephant noses are foiled by puff adders.

Even an elephant can't detect the smell of a puff adder.

Miller: They are hiding their scent in some way or another.

They are not producing an odor that other animals

Are cuing in on.

Narrator: It seems this snake is scentless after all.

This is extraordinary findings, really,

Because this is a world first.

Miller: This is the first example of scentlessness

In a terrestrial vertebrate species.

Narrator: The question now is,

How does the puff adder prevent itself from smelling?

Ash is still investigating this part of the mystery,

But she has some ideas.

I'm so... I don't want to give this away, though.

Narrator: Oh, go on, ash.

Give us a clue.

The theory that we're investing all of our focus

Into at the moment is the idea that the scales have a role

To play in the scentlessness and that they might somehow

Either be absorbing odors from around its environment

Or that it doesn't allow odor to come off of them.

Narrator: By camouflaging its body and concealing its scent,

The puff adder has found the secret to invisibility.

This is one seriously sneaky snake.

Narrator: May 2018, ontario, canada --

Edward trist and his family

Are taking a fishing trip

When they come across something strange.

[ lynxes shouting ]

♪

Two canadian lynx face off in a very vocal way.

[ lynxes shouting ]

♪

It genuinely sounded like my little nieces doing it.

Narrator: This is not a hoax.

The sound is real, but what on earth does it mean?

Narrator: In ontario, canada,

A family witnesses a close encounter of the feline kind.

[ lynxes shouting ]

Two lynx go head-to-head

While making really strange sounds, but why?

Cooke: Perhaps they're just having a family tiff.

[ lynxes shouting ]

Schreiber: Maybe they're just battling out

Some sort of domestic issue,

Unaware that they're being filmed by some amateur filmer.

Cooke: Lynx are solitary creatures.

They're normally found haunting the forests,

And they rarely meet.

Narrator: The only groups you'll see are mothers with their young,

Who will hunt and play together.

Kittens will stay with their mother

For a whole year after being born,

So it's possible that these two are siblings.

Narrator: But this doesn't quite add up.

Siblings are affectionate,

Grooming and curling up with each other,

And this exchange is pretty intense.

[ lynxes shouting ]

This is not some sort of sibling rivalry.

This is two random adults

Appearing to be caught in aggressive conversation.

Narrator: So not a family tiff.

Could this be two male lynx

Having a turf war over territory?

Cooke: Males occupy different territories.

So one obvious thinking behind what's going on here

Is that they've met up.

They both think they own this bit of land,

And they're having an argument about it.

Narrator: But the altercation in this clip

Is all banshee and no bite.

Is this normal for a territorial dispute between lynx?

If it were two males, then it would be very likely

That this encounter would escalate

Into a very aggressive one.

We would have seen a full-on brawl there.

Narrator: You mean like these guys?

Okay.

Our video seems a bit tame after that,

So perhaps not a territorial dispute.

Then what links these two lynx?

Could it be the oldest story in the book?

Male and female lynx are identical.

It's impossible to tell them apart,

So perhaps we're looking at a male and a female.

Lynx inhabit areas with very cold, harsh winters,

So they tend to have very seasonal breeding patterns.

Narrator: A female will call out to say she's available,

But males had better be quick

Because she will only mate once a year.

They tend to mate in the spring.

What we're looking at now took place in may,

And what looks to me that's happening

Is this is a male who's on the prowl to mate.

Unfortunately for him, he's arrived a bit too late.

Most likely she's already pregnant.

Narrator: By may, mating season is well and truly over,

And females are likely to be off limits.

This is a typical sort of behavior

Where the male is coming on to the female,

But she's letting him know that she's not interested.

Narrator: And it takes quite a bit of noise

Before he understands.

Schreiber: So effectively, we're watching a very sad scene here,

A male trying to court a female,

But he's left it way too late, and she said, "I'm sorry.

I'm uninterested in your crazy growl advances."

Yeah, tough luck, guy, next year.

♪