All language subtitles for Great.Blue.Wild.S03E03.WEBRip.x264-ION10

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.

[♪]