Original subtitles

NARRATOR: The coast of Mozambique belongs to giants,

from the leviathans that visit each winter,

to the resident whale sharks that feed here year-round.

But a closer look reveals a tiny, secretive world,

few have explored.

NAKIA CULLAIN: While most people come to Mozambique

to see these big mega-fauna species,

they don't realize thatthere's this whole other life

going on in the shallows.

Tiny little species that get overlooked.

CALUM MURIE: They deserve just as much protection and attention

as the bigger guys.

They're just as rare and justas important to ecosystems.

NARRATOR: In this land of giants,

the smallest creatures must find a way to survive

on this wild and unpredictable coast.

[♪]

It's winter in Mozambique, along Africa's southern coast.

And the humpback whales have arrived from Antarctica.

Each year, hundreds make the 4,000 mile journey north,

to mate and breed in these warmer waters.

NAKIA: -Sometimes you see the humpbackswhile you're diving,

sometimes you don't, but you can always hear them.

NARRATOR: The male humpback whale's song is one of the longest,

and most complex of any animal.

A single call can last up to 30 minutes.

Once it's over, the whale will start again,

repeating the same song, over and over.

The song travels far underwater.

Researchers believe some of these low frequency sounds

can be heard more than 10,000 miles away.

These are some of the loudestsounds made by any animal

on the planet.

NAKIA: It rumbles in your soul, it's very beautiful.

It's very special.

NARRATOR: Why male humpback whales sing

remains a mystery to researchers.

It's possible males sing to attract females

or as a display of dominance over competing suitors.

One thing is certain, thewhales' communication is vital

to their survival.

Every winter, Nakia Cullain studies the humpbacks

that migrate here to learn how they use this coast.

NAKIA: We do humpback surveys.

So we climb up to the top of asand dune and we do scans

on the half hour.

We do minimum four-minute scan

and we record all of the behavior,

the numbers, we map it as well.

We're getting an idea of how many there are,

how they're using our bay and what they're doing.

NARRATOR: Nakia's research station Zavora Marine Lab

sits on a remote stretch of coastline

in southern Mozambique, hugging the Indian Ocean.

The humpbacks come to Mozambique's warmer waters

to mate then go off to breed during winter.

Humpback whale seasonmight be the most exciting time

for researchers and tourists.

But away from the deep blue, there's another world

worth exploring.

And Nakia refuses to let the little species go unnoticed.

The shallow reefs, the estuaries and the mangroves

are filled with tiny creatures.

Some, smaller than a match head.

NAKIA: -We find tons of macro life inour inshore-offshore reefs

but also in lagoons, estuaries and mangroves.

There's a whole bunch ofecosystems here in Mozambique

that inhabit a lot of macro-fauna.

NARRATOR: While the humpbacks are mating offshore,

so too is one of Mozambique's

smallest and strangest residents.

But getting to them isn't easy.

Research in the shallows is governed

by the turn of the tide.

Nakia and her team have a shortone-to-two hour window.

Just twice a month, to study these secretive creatures.

When the tide is at its lowest, a rocky shoreline reveals itself

as the ocean retreats from the bay.

For three hours tiny marine life

is left stranded inside the water-filled grooves

and pores of the rock face.

Each little pool is alive withbarnacles and small fish.

Seaweed carpets the rocks.

NAKIA: We're really lucky in Zavora

because on top ofhaving our little small pools

that are exposed at low tide,

we have this much larger pool that we sample in

larger than a typical swimmingpool and up to three meters deep

so it's quite a large

and it allows us tosample this diverse marine life

in this constricted area.

NARRATOR: The giant rock pool allows Nakia to reach her quarry:

Nudibranchs, brightly colored slugs.

We know little about.

Zavora Lab runs the mostextensive study on nudibranchs

in the country.

Its database includes more than 200 species.

Ninety percent of which arenewly discovered in Mozambique.

NAKIA: -It makes it really special to goout and look for these guys,

it's just fascinating.

These species that not many people are studying

or researching or caring about.

NARRATOR: There are more than 3,000 species of nudibranchs,

at Zavora lab alone, 30 new species have been found

and scientifically described in the last eight years.

Many of those were discoveredhere, in the rock pool.

But there's a challenge:

The same tide thatgrants them access to the pool

also restricts their survey time.

NAKIA: -We rely heavily on the tides inorder to enter the rock pool,

which gives us a very small window within a month.

NARRATOR: The rock pool is 650 feet offshore.

Powerful waves make it too dangerous to swim out to it

at high tide, so they must waituntil the tide recedes.

But even a normal low tide isnot enough

which is why the pool is only accessible

for two hours twice a month.

This is due to the ellipticalpath the moon follows

as it orbits the earth.

As the moon revolves around the earth,

it exerts a gravitational pull.

When the moon is closer to theearth, the force is stronger,

creating a higher tide.

When the positions of the moon and sun align,

the gravitational pull from both

combine to create extra strong tides.

This extremely low tide twice a month,

allows the team to walk out to the pool.

With a short window to searchthe entire rock pool

finding these crafty slugs is no easy feat.

Most of the nudibranchs that live here are no larger

than the size of a pinky finger.

And many are experts at camouflage.

The team will have to work fast, to beat the tide.

Locals not fortunate enough to own a fishing boat

also take advantage of the exposed bay.

They carefully inspect each rockfor mussels and other shellfish

and pick them off one by one.

For others, the extreme low tide presents

an opportunity for fishing.

They will stay out to find food for their families

for as long as the tide permits.

Nakia treads carefully past the smaller pools

on this porous coastline.

But the current is strong.

She struggles to cross.

As water forces its way through deeper trenches,

sharp rocks, slippery weeds and powerful waves

delay her crossing.

Finally, she reaches the rock pool.

The struggle was worth it.

NAKIA: It's almost like a miniature coral reef in there.

That you wouldn't expect to seewhen you're standing on shore.

Looking at this giant rock and once you enter it

it's a whole new world.

There's so much life that you're always finding

new things every time you go there.

NARRATOR: Today, Nakia has little time to admire

the beautiful surroundings.

Getting here has cost her nearly an hour.

She now has just 60 minutes tosurvey the 650 foot pool.

In a search of creatures,

most of which are smaller than a fingernail.

And are experts at camouflage.

Nudibranchs range in length froma fraction of an inch

to an entire foot.

Their jelly-like bodies are canvases

that bear some of the mostfascinating patterns and colors

of any animal on earth.

Some nudibranchs use their vibrant hues for camouflage.

Others display bright colors as a warning sign

to would-be predators.

An indication that the slugs are poisonous.

There are two main types of nudibranchs:

Dorid nudibranchsbreathe through a plume of gills

on their back end.

Aeolid nudibranchs have finger-like appendages

called cerata that cover their back.

These appendages are used forbreathing, digesting food,

and for self-defense.

Both types of nudibranch arm themselves with poison

by eating toxic animals.

Though Dorid nudibranchs can't sting,

they can absorb toxins from food,

like sponges and coral.

The slugs are able to store these toxins

in their extremities

and release them to ward off attackers.

Nudibranchs evolved from sea snails.

And developed these defenses

when they lost their protective shell.

Nudibranch means naked gills.

Describing the feathery bouquet

that protrudes from their backside.

These ornate plumes of gills enable them to absorb oxygen

from the water.

Some guard their gills with asacrificial appendage

that hangs overtop.

Better for a predator to attack the decoy

than the delicate organ it protects.

This nudibranch is laying eggs.

A ribbon-like spiral of as manyas one million ova.

Nudibranchs are hermaphrodites.

They reproduce by fertilizingone another's eggs.

Since they possess both male and female organs,

Nudibranchs can mate with any other mature member

of their species.

Maximizing their chances to conceive.

After mating, each of the partners will lay eggs.

-If conditions are right, -Nudibranchs can mate year-round.

But Nakia believes this is the time of year

they're most active.

She's eager to document some mating pairs

to validate the findings from past years.

And prove there is some seasonality

to the nudibranchs' breeding behavior.

She enlists the help of one ofher volunteers, Marie,

to cover as much ground as quickly as possible.

NAKIA: We'll enter the rock pool, we'll start our stopwatch.

And every time we find anudibranch we'll stop the timer.

And that way we get an idea of how much time it's taken

to find each nudi.

NARRATOR: Nakia and Marie scour the rock pool.

After six minutes, they find one.

It's a hypselodoris.

Often called a painted nudibranch

for its vivid colors.

A sprinkle of dark blue andyellow dots decorates its body.

The vibrant colors suggest thisnudibranch is armed with toxins.

Nudibranchs use a pair ofantenna-like horns on their head

to scout out food.

These are called rhinophores.

Greek for nose carriers and just like a nose

the rhinophore is used to smell.

Nudibranchs are blind to their own beauty

and to their surroundings.

They rely on smell alone to huntand to navigate their way

through tricky terrain.

Like the edge of this rocky outcrop.

This nudibranch stretches outin the hope of bridging itself

onto another piece of substrate.

Its horns move about like antennae.

But they don't detect an easy way across,

so the nudibranch turns back around.

On its rear is its plume of eight gills,

through which this tiny slug breathes.

These little nudibranchs cangrow up to an inch-and-a-half

in length.

This one, at merely a fraction of an inch,

has a long way to go.

NAKIA: Once we find a nudi we measure it,

we identify what substrate it's on, the depth it's at

and whether it's doing any behavior

so if it's mating or feeding.

NARRATOR: Nakia completes the measurements.

And Marie goes in for a photo ID.

MARIE-MICHELLE SIMARD: The photographs are really useful

because we bring them back to the lab

and we use them as a reference to figure out

what the actual species is.

NARRATOR: Nakia is familiar with this dorid nudibranch

and makes fast work of recording the information.

Nakia and Marie re-start their watches and the race

to find the next species resumes.

Nakia's next find is aTessellated Halgerda nudibranch,

named for its intricate mosaic pattern.

Bright-yellow geometric ridges decorate

its brown, polka-dot body.

The sea slug is just an inch-and-a-half in length.

But under a macro lens, an unwelcome guest

makes it look like a giant.

This nudibranch is host to anectoparasite, a tiny copepod.

Despite its size, the parasitecan do a lot of damage.

Research shows that infected nudibranchs

produce up to 50% fewer eggs.

Nakia and Marie spot several other sea slugs.

This black-and-gold sapsuckingslug shares many characteristics

with nudibranchs.

It produces a distasteful secretion

to protect itself from predators.

And similar to nudibranchs,

its bright coloration is a warning to hunters.

But this slug doesn't have a plume of exposed gills.

A distinctive feature of a nudibranch.

It's a good day for Marie and Nakia.

They manage to find six different species

including a mating couple.

But all the species are re-sightings.

MARIE-MICHELLE: You go out hoping to find new species

and the conditions make it really difficult.

The water starts filling back up

and pushing us out of the rock pool.

Which can be quite dangerousthere's a lot of sharp rocks,

barnacles, you can cut yourselfvery easily and hurt yourself.

NARRATOR: Their time has run out.

The bay is quickly filling up.

The team must hurry back.

So must the locals.

The tide dictates not only Nakia's research,

but also the livelihood of thepeople that live on this coast.

An estimated two-thirds of Mozambique's population.

More than 300,000 people here rely

on small-scale coastal fisheries to survive.

Fish accounts for nearly half the country's diet.

Those who collect mollusks and fish at low tide,

practice sustainable fishing.

They only catch enough to provide food

for their families.

But not all local fishermen abide by the law.

As the tide comes in the boats go out,

armed with illegal gill-nets.

That are hung vertically in the water and designed

to trap fish by their gills.

These nets are one of the mostdangerous threats

to marine life.

Both big and small on this coast.

NAKIA: Here in Mozambique,

we do see some gill-netting right off of our coast,

specifically right off the rock pool.

-NARRATOR: -Locals net this contained area.

Catching all the life that's already been trapped

by the tide.

This method of fishing isn't selective.

Many of the animals caught in the net are killed

but never eaten.

Smaller fish are the target,

but it's the capture of coastal giants,

that's drawn attention to thisdestructive fishing practice.

Gill-nets are set up along the migration routes

of Mozambique's largest animals.

Destructive fishing practicesalong this coast

impact both the largest and the smallest

of Mozambique's marine creatures.

And it's hard to save those, you don't see.

Farther up the coast,

seventy miles north of Zavorais Tofo beach.

Here, macro-enthusiast Frida Haraldsson

fights a similar battle.

To try to raise awareness about the tiny species

that are often overlooked.

FRIDA HARALDSSON: A lot of people focus on conservation

when it comes to larger species,

very iconic species whetherit's on land or in the ocean.

But it's easy to forget about the small things.

Bottom dwellers like crustaceansare definitely threatened

and it's a shame it's just notcoming more into the light.

NARRATOR: Frida is the head scubainstructor at Peri-Peri Divers.

FRIDA: For me this coastline is super special.

I haven't managed to dragmyself from here for seven years

there's so much diversity.

You get drawn here because of stories

of whale sharks and mantas.

Then there's the whole world of macro

that you didn't expect you neverknow what you might see.

NARRATOR: Each time Frida takes a group diving,

is an opportunity to change someone's mind.

FRIDA HARALDSSON: People come here to see big things

'cause that's what this region is known for,

which is brilliant and there'slots of lovely big things here

but the macro here is just so fascinating.

It's great to havean encounter with a manta ray

but when you discover new little species

and then also just the thrillof actually looking

for that thing and finally finding it.

That's why I just find it so much more rewarding.

NARRATOR: -Frida's keen eye for spottingmacro life on the reef

sets her apart from most divers.

Unlike Nakia, Frida doesn't workwithin a contained environment,

like the rock pool.

She must locate the macro critters,

on the offshore reefs they sharewith Mozambique's giants.

-FRIDA HARALDSSON: -Keeping track of smaller things

is obviously a lot moredifficult than bigger things.

It's harder to spot them first of all. Then also

they might have habitats wherethey're a little more hidden.

And so it's quite difficult to estimate populations

in the same way.

NARRATOR: But you can find them if you know where to look.

FRIDA HARALDSSON: -A lot of the smaller things tendto have a particular habitat

they belong to.

So then I do have lots of little places I know,

so it's quite nice that you can keep track of them

in that sense.

NARRATOR: -Many macro critters use otherorganisms for protection.

Sea cucumbers, urchins and anemones

often play host to these tiny tenants.

Sea cucumbers come in different shapes and sizes,

depending on what part of the world they live in.

Some can grow as long as ten feet.

They're the street sweepers of the ocean.

They creep along the seabed,

collecting minute particles of food.

Crustaceans, some smaller than a fingernail,

make it their job to clean this cleaner.

These tiny guests pick algae and parasites

off the skin of their host.

In exchange for a hiding place and a lift.

This commensal shrimp is the ultimate hitchhiker.

Other species, like the zebra crab,

hook their barbed feet onto sea urchins

seeking protection among their spines.

On Tofo's reefs,

the crustaceans seem to favor anemones as hosts.

This fanned appendage belongsto the Peacock Tail Shrimp.

Also known as a clown partnershrimp for its tendency

to share its home with the clown fish.

Its inch-long, partially transparent body

blends into the anemone.

Large white spots decorate its back.

The shrimp has a special mucous coating

that protects it from the sting of its host.

It's actually the anemone that secretes the coating.

As with most crustaceans,

this tiny shrimp must molt itsexoskeleton in order to grow.

When it does, the shrimp willbe vulnerable to predators,

and to its host's sting.

It will need to fend for itself on the reef,

until a new exoskeleton grows.

And the shrimp can once againapproach its host anemone

to cover its body with the protective mucus.

The harlequin crab faces thesame life-and-death challenge.

As the walls of its host, a tubeanemone, blow in the current.,

the crab is exposed for a few brief moments at a time.

For now, it's safe.

Until it needs to leave to scavenge for food.

A pair of porcelain crabs

devises the perfect safety strategy.

They eat from the comfort of their protective home.

The current acts as a food-delivery service,

bringing plankton to their doorstep.

The crabs extend their front arms out from the anemone

to collect the food.

If they lose a limb to an opportunistic predator,

it will regenerate after a few molts.

Feather-like appendages attached to its front arms

reach into the current

to filter the passing water and trap the plankton.

This technique allows the porcelain crabs

to stay protected by theanemone's stinging tentacles.

And feed at the same time.

For this crab, safety is the main priority.

This female is carrying as manyas 1600 eggs in a brood flap

below her abdomen.

FRIDA HARALDSSON: Just getting a glimpse of these creatures' lives,

it's just that really lovely feeling.

When I'm down there it's justsuch a nice getaway.

You can hover perfectly just above them,

and it's like you're just sitting there

like a little fly on the wall.

And just watching them in their normal environment.

What they get about tobecause they really don't mind

that you're there.

NARRATOR: While many of the reef's animals seek partnerships

with larger organisms for protection,

others use color and pattern to blend in.

Or to stand out.

A radiantly colored shrimp rests on the sandy bottom,

unprotected by an anemone.

But this harlequin shrimp is no pushover.

Despite its tiny size, the inch-long crustacean

is a fierce predator.

Harlequin shrimp hunt in pairs.

Starfish are their favorite prey.

Once they have their target, the shrimp work together.

One shrimp uses its claws to clip the starfish's feet,

detaching it from the seabed.

While the other flips it on its back.

These ferocious little predators are also known

to drag prey back to their lair,

where they will feed on itfor days, sometimes for weeks.

All while the starfish is still alive.

Harlequin shrimp have fewnatural predators of their own.

Their brightly spotted bodies serve as a red flag

of toxicity to attackers.

But these mesmerizing hues and patterns

attract another predator.

Humans.

FRIDA HARALDSSON: A lot of people want these magnificent-looking shrimp

like the harlequin shrimp.

And people seem to forgetthat they're also under threat

by the aquarium trade.

NARRATOR: -At the moment Frida sees thesemacro species regularly

on her dives.

In their same hiding places, time and time again.

FRIDA HARALDSSON: If they keep on coming back to the same place,

it looks like it's a lot of them around,

seems that they're doing quitewell at the moment at least.

NARRATOR: The same can't be said foranother species also targeted

for the aquarium trade: the seahorse.

Unlike the reef's macrocreatures, which are safeguarded

by deep water and a 10-minute boat ride,

the seahorses here are unprotected.

Their home is a shallow lagoon within the estuary:

an environment easily accessible to humans,

and constantly threatened by humans.

NAKIA CULLAIN: -They're used for the aquariumtrade and traditional medicine

so dead or alive these seahorsesare worth a lot of money.

NARRATOR: Every year more than 150 million seahorses

are killed for the traditionalmedicine trade alone.

In some Chinese cultures, seahorses are believed

to cure a variety of ailments, from heart and kidney disorders

to impotence, even though thereis no evidence to suggest

they have any medicinal value.

Hong Kong is the centre of the trade.

Demand is so high that dried seahorses sell for as much

as 1,400 US dollars per pound.

In 2014, customs officers in Hong Kong seized 150 pounds

of dried seahorses from Mozambique,

That's nearly 35,000 seahorses.

NAKIA CULLAIN: What we're trying to do is monitor these populations.

And hopefully get somesufficient data to support their

status and hopefully help their populations here.

We specifically come here to study the seahorses.

They are data deficient here inMozambique so we don't really

know how their populations aredoing although we do suspect

that they're declining.

-NARRATOR: -To study Mozambique's seahorses

in the estuary's lagoon, Nakia and her team are once again

at the mercy of the tide.

NAKIA CULLAIN: We try and enter the lagoon in between tides.

We want to stay consistentwith our protocol so we enter

at the same spot and we swim the same direction,

and then come back in the same direction

to maximize our search time and survey the habitat.

Our surveying in the lagoon is very shallow

so not more than 2 meters.

In these shallower environmentswe really have to get

our buoyancy under control.

We don't want to disturb thesespecies that you might not see

that are hiding in the sand.

NARRATOR: This pair of eyes belongs to a flounder,

one of the reef's best-camouflaged fish.

But it wasn't born this way.

For the first few weeks of life,

flounders look and act like typical fish fry.

Eventually, one eye migratesto the other side of its body

to join the other.

As the fish metamorphosizes to begin life

as a bottom-dwelling young adult.

Then the flounder settles to theseabed, where it's skillfully

camouflaged, with both eyesfacing up and above the sand.

Not all hiding techniques are this extreme.

The spearing mantis shrimpsimply ducks inside a burrow.

Others blend in against blades of seagrass.

Nakia's seahorses are also experts in camouflage.

They're capable of changing color, and growing filaments

to blend into their environment.

And she and Marie have just 90 minutes to find them.

NAKIA CULLAIN: They can be quite tough.

Some of them are quite small.

They tend to wrap themselves around eel grass blades

and it can make it difficult.

They hide within the grass.

We try and be as observant as we can.

You know you see it and then you look away and it's gone

and you're 'where did it go?'

So you really have to keep an eye on it.

And you have to be very, veryattentive to what's around.

NARRATOR: Finally, they've got one.

It's a male giraffe seahorse, identified by its short snout

and a horn-like eye spine.

NAKIA CULLAIN: We first take as many photos as we can,

so we can identify them as individuals.

One person will photograph, theother person will measure.

And we'll record the size, sex, what substrate it's attached to,

the depth we found it at, and if it's a pregnant male.

NARRATOR: -Seahorses are the only specieswith a true reversed pregnancy.

The female transfers her eggs to the male,

where they're fertilized in his pouch.

The seahorse's facelooks kind of like a horse's.

It has the prehensile tail of a monkey and the brood pouch

of a kangaroo and yet, it is a fish.

But unlike most fish, the seahorse's body

isn't streamlined to glide through the water.

Instead, it relies on a dorsalfin that beats 30-70 times

a second to propel the animal forward.

Pectoral fins on either side of its head

help with steering and stability.

As a result, seahorses are very poor swimmers

and spend most of their time gripping onto grasses

to prevent themselves from being washed away

by strong currents and waves.

There are 54 known species of seahorse worldwide.

Seven known species live here in Mozambique.

Nakia inputs information abouteach seahorse she discovers

into a database, to monitor the population

and behavior of each species.

Today, Nakia and Marie have spotted just two seahorses.

Compared to last month'smore successful survey of five.

NAKIA CULLAIN: I find it very important to study the populations here

and hopefully get some published work out there.

To allow their status to be more known.

They're vulnerable, beautiful, interesting creatures

that I think are neglected in the data world.

NARRATOR: -The seahorses' lagoon is justone part of a larger estuary.

Here, fresh water rivers meet salty seas, creating

one of the most productive environments on earth.

Thousands of species, from birdsto fish, depend on this habitat.

Lesser flamingos pick algae andcrustaceans from the shallows.

Many species of fish rely on this habitat

to spawn and nurse their young.

And entire ecosystems hinge on its services.

Seagrass beds line its shallow bottom,

and mangroves skirt its edges,

serving as a buffer zone between land and sea.

Water draining downstream carries nutrients, sediments

and pollutants to the estuary.

This runoff water flows through marshes,

which act as filters to create clean, clear water.

The estuary also provides habitat protection.

Eel grasses and mangroves reduce wave action,

and stabilize sediment.

So its inhabitants cannot only survive, but thrive.

Underwater Africa's Calum Murie works to protect the estuary

and its part-time dwellers, the juvenile fish.

CALUM MURIE: We do surveys to examine how many different types of fish

there are, how much of each of these species there are,

how these species interact, where they live.

Once we gain an understanding of this,

and a full understanding of the animals' niche,

which is all the conditions that an animal needs to live

within an environment, then wecan protect them a lot better.

We pass this information ontothe fisheries department

and on to the local communitiesin order to give them

the information they require to put their own

conservation practices in place.

NARRATOR: Currently, the biggest threat to the estuary

is the use of mosquito nets for fishing.

Malaria, transmitted through thebite of an infected mosquito

is a serious threat to the people of Mozambique.

Mosquito nets are common and far cheaper

than traditional fishing nets.

But they are a poor substitute.

The fine mesh catches the tiny juvenile fish

before they reach maturity.

A process that happens here, inthe estuaries and the mangroves.

CALUM MURIE: They are where juvenile fish hide out and grow to a size

where they can defend themselves.

Some species will move out to pelagic environments,

some will go to reefs,

but these mangroves are where it all starts.

And by protecting them we should be providing the fuel

that these reefs need to keepgrowing and keep supporting

the local communities.

It's about being sensible andputting proper management

in place that still allows people to go out and fish

and make a living but in a way

that doesn't impact future generations.

NARRATOR: -Locals have harvested reef fish, shellfish and crustaceans

in these waters for centuries.

For these fishermen,

maintaining healthy marinelife is a matter of survival.

Each week, Calum and a team of volunteers

survey the mangroves and estuaries.

They travel in traditionalfishing vessels called dhows.

The journey takes several hours and considerable planning.

Once again, the researchers areguided by the turn of the tide.

CALUM MURIE: -The estuary is like a massivesink so once it starts to drain

and the tide drops the currentjust picks up and picks up

so that's quite a constraint when you're trying to do

fieldwork and you're just beingflown along in a ton of current.

These things all act to limit our research

but it's a challenge that we enjoy

and we have to think through

and it adds to a more meaningfulkind of result when you get it.

NARRATOR: Calum and his volunteers will take photos and videos

of the animals they encounter

along with any behavior they observe.

The inhabitants of the estuary have adapted to life

in these sandy shallows.

A cockatoo waspfish, just five inches long,

takes shelter behind a rocky outcrop.

Others, like the hermit crab,

wear their protection on their back.

The shell serves as a portable home for the crab

and the barnacles on the shellget free transportation.

Hunters, like the frogfish, blend in with rocks and corals

to ambush prey.

More active predators like eelsslither through the seagrass.

Some use their shape and color to expertly blend in

with the environment.

CALUM MURIE: We identify all the animals,

go through all the data we've tracked.

So where they're living, what they're doing.

And then we have a look and putthem into our database of all

the different species that we'veever found and have a look at

their conservation status around the world.

If they're critically endangeredor in concern around the world,

we can use this information toadd extra weight to our argument

that these areas deserve special protection.

NARRATOR: So far, just one area of the estuary

has received marine protection status,

A small victory for the tiny creatures that live there.

But there'sstill a lot of work to be done.

What happens to these tiny animals, In the mangroves,

the lagoons,

and the shallow reefs of Mozambique is important.

Every juvenile caught at the lagoon

is a fish that doesn't make it to the reef.

That doesn't become prey for larger fish.

That doesn't energize a much greater ecosystem:

CALUM MURIE: This place is just so unbelievably special

that the only option for me is to try and see

this entire coastline ofsouthern Mozambique protected.

We need to convince people hereof the quality of the resource

that they have, how otherlocations in the world have used

this resource to their benefit, and how Mozambique itself

can grow on the back of such an incredible resource.

NAKIA CULLAIN: -It's unique, it's diverse andit provides us an opportunity

to go out and look for and discover these new species.

FRIDA HARALDSSON: You just see new things every day.

Just such an amazing feeling.

NARRATOR: On this untamed coast, wheretime is marked by powerful tides

that uncover fascinating ecosystems,

marine researchers will continueto fight for the tiny creatures

that live their lives in the shadow of giants.

[♪]