Original subtitles

The waters off Mozambique's wildcoast are home to marine giants.

The world's largest and most elusive stingray

and the greatest fish in the sea

parade along the coast feeding in its nutrient-rich waters.

But even the ocean's largest animals are defenseless

against reckless overfishing.

It's an urgent issue and we need to start making some changes

here to save these species.

You start to realize that ifyou don't stay and fight for them,

on one else is going to.

Now, Mozambique's leading marine researchers

set out to find one of theocean's most secretive animals.

And protect its most well-known before it's too late.

It's a race against time to savethe giants of Mozambique.

The waters of Mozambique teem with marine life.

The Western Indian Ocean pumps nutrients along this coast,

inviting some of the ocean's most exotic

and most-loved marine giants.

It's almost like a perfect storm.

A situation where the continental shelf drops off

really close to shore

so it generates a lot of upwelling here or

a lot of nutrients being pumped along the coast.

So you just get a lot of biodiversity here,

a lot of food here.

A resident population of juvenile whale sharks

feeds along the coast gulping up the plankton-filled water.

Migrating humpbacks use thecoast's warmer waters to breed.

Pods of dolphins skip through the water,

chasing after smaller fish that have come close to shore

and close to the surface to feed.

Providing the dolphins with a small feast.

A rare giant also makes an appearance,

as it surfaces on the coast.

The mola mola, or ocean sunfish, weighs as much as a bull

and is the heaviest known bony fish in the world.

This to me is one of the mostcritical habitats in Africa.

I call it the blue heart of the east coast here

and I really do believe it's oneof the last blue wildernesses

left in Africa.

The wild coastline of Mozambique stretches along

more than 1600 miles from Tanzania to South Africa.

Andrea came to Mozambique's Tofobeach to study manta rays

in 2002.

And never left.

She established the Marine Megafauna Foundation.

An organization dedicated to theprotection and conservation

of larger marine species.

I arrived to the most pristine environment I'd ever seen.

You could walk on the back of whale sharks here,

there was mantas everywhere, turtles everywhere.

It was like utopia for me

and especially for a young marine biologist

you couldn't get better than this.

But things have changed drastically for the worse.

As I saw things changing, asI saw development happening

and as I saw these fisheries

starting to barter for things like shark fin,

I realized that what I'm fighting for.

I'm fighting for that picture ofMozambique when I first arrived.

I just won't be satisfied untilwe can bring it back

to its original splendor.

Seventy miles down the coastat Zara Bay.

The manta ray population is healthy

and there is little-to-no impactfrom recreational diving.

But local fishing practices posea big threat.

Nakia Cullain, fights to preserve

what is for now a pristine coast.

They put out these large nets

and unfortunately their target is smaller fish

but a lot of other bigger species

get trapped in these nets.

A lot of the locals here are self-sustaining.

So by fishing, they support themselves and their families.

The problem is, the fishing nets are placed along the shoreline,

intercepting the migration route of larger species

such as rays and sharks.

Nakia and her partner Mornay run Zara Marine Lab.

A research station established in 2009

to investigate and conserve thecoastal ecosystems of Zara Bay.

It's set on one of the most remote stretches

of Mozambique's coastline.

A place where many of the reefsare yet to be explored.

It's wild and it brings in alot of different marine life

so the diversity is amazing,

the remoteness and thequaintness of it is fascinating

and it allows for us to do some research

that's never been done before.

Nakia hopes to learn more about which reefs

the manta rays use most and in what numbers.

This information will help her monitor the population.

And protect the migration routesof these marine giants

from local fisheries.

The murky, nutrient-rich water along Mozambique's coast

attracts many filter feeders.

Among them, the giant oceanic manta ray.

A larger cousin to the smaller reef manta

which Andrea first established as a separate species

in 2008.

It's one of the largest new species

discovered in the last 50 years.

A lot has been learned about these gentle giants

in just a short time.

We've identified more than athousand individuals living

along this coastline.

We've documented a lot about their reproductive ecology.

We've learned about their predation.

We've learned a lot about the population genetics

and how these animals are mixing in different parts

of the coastline.

We really have done some of thekeystone work on manta rays.

While researching manta raysAndrea uncovered another giant.

One she's never seen before.

I started noting when we werediving this really large ray

that I was completely unfamiliarwith.

I couldn't even ID it.

It was this crazy mystery, you know,

trying to figure out what this animal was.

One of our friends who worked inIndonesia

eventually helped us ID it as a smalleye stingray,

which is a very rare animal

that comes up mostly in fisheries around the world.

But very few people encounter it alive

and very few people have any data on this animal.

So we were shocked that we hadsuch a rare animal living here.

More than seven feet wide,

the smalleye is the largest of all stingrays.

The ray is named after its small, beady eyes

which leave the animal with poor vision.

We were shocked even morewhen we found it has never beenseen

west of the Maldives.

So we actually wrote a paper back then

and did a range extensionshowing that they actually live

along the eastern coast of Africa

but then we were tasked with finding out more

about this animal,

which is really hard when you don't see them very often.

The rays are so rarely sighted

researchers can't begin to guessthe size of their population.

Andrea's records show sightingspeak in September and October.

With a short two-month window ahead of them,

she and her assistant Anna

set out to find and tag the smalleye stingray.

One of the ocean's rarest creatures.

They don't distribute evenly, they prefer certain reefs

so we're actually going to target those reefs today.

It's going to be great to try and learn where they're going

and what they're eating

and where they are when we're not seeing them.

Hopefully in the same way that we do with manta rays,

we can find out how large the population is

by taking the ID shots of the spot patterns

that they have on their backs.

We'd like to be able to start with telemetry,

putting some tags on them and finding out

how they use the local habitats,

how far they travel.

So really, the world's largest stingray,

we know nothing about it

and that's what we're endeavoring to do,

learn more about this awesome animal.

The visibility isn't ideal.

But Anna and Andrea hope they'llbe able to spot the smalleye

if they see it.

The temperate reefs along Tofo'scoastline appear dull and rocky

in stark contrast to the colorful coral reefs

of the tropics.

The lack of color on this reef

makes the researchers' jobs much more difficult,

as they try to spot well-camouflaged animals

through water clouded by plankton.

Many, like this alligator fish disappear against the rock.

As they scour the reef for smalleyes,

a curious potato bass joins them.

It's named for the large potato-sized markings

on its body.

The potato bass or potatogrouper can grow to seven feet.

It's one of the largest predators on the reef.

Despite their round physique,

potato bass are extremely swift hunters.

But this one seemed content to just hang out.

There was this potato bassthat wouldn't leave us alone.

It was trying to bite my strobe...

and everywhere we went it seemed to be following us.

Potato bass tend to be inquisitive toward divers.

As a result, they make easy targets for spear fishermen.

Because it's so big the potato bass

is a sought-after trophy fish.

Its survival is now threatened by overfishing.

Anna grabs a photo ID of the fish

so the team can keep an eye

on this friendly giant on future dives.

Still no sign of the mysterioussmalleye stingray.

There are no rays here at the moment.

But the information they've collected over the years

indicates this reef is a hotbedfor both manta rays

and smalleye stingrays.

Anna and Andrea deploy a listening station

that will record activity on the reef,

when they're not there to monitor it themselves.

The acoustic station picks up pings from tagged manta rays

as they pass by.

If Anna and Andrea are successful,

this listening station will also pick up pings

from the first-ever tagged smalleye stingray.

The equipment is ready.

Now the team just needs to finda smalleye stingray to tag.

Down the coast at Zara Marine Lab, Nakia and her team

hope to find and ID manta rays at an inshore reef.

Andrea's network of acoustic listening stations

and her photo database

have helped her document more than a thousand

individual mantas at Tofo.

Here at Zara, Nakia and her team

have logged fewer than 400 mantas.

And there is no network of tags to track the rays.

It would be nice to start tagging with the mantas

so we actually know their migratory patterns

and what they're doing.

There's a lot of unanswered questions

and I'd love to get to the bottom of it.

The team heads out to find answers.

Nakia needs to identify which reefs the manta rays favor.

So she can install acoustic listening stations

to monitor their whereabouts.

But working on a wild, remote coast is never easy.

Nakia and her team face their first set of challenges

before they even get on the water.

Normally, what we do

is the tractor will pull the boat along the beach

and then when we get to the launch spot

the tractor will launch us into the water,

usually with the back first.

But with today's sticky, wetsand and rough seas,

this isn't possible.

So it's on to Plan B.

They ask us to and push, push, push through the waves,

over the waves, and then we hop on the boat

and we head out.

Nakia and her team continue to battle the elements.

We tend to have a lot of plankton in the water,

which in turn leads to bad visibility for us divers.

However, it does bring in a lotof our big megafauna

and for us we photo ID for a lot of our surveys

it can be challenging to fight through that visibility

and the heavy surge and the swell.

So definitely poses challenges

but we continue to go out and sample.

When you go down in this water, yes, the viz is not so beautiful

but you go down and you've got this feeling of it's

you, your soul and the water around you

and the creatures around you.

When you see animals in their natural habitat,

you get a certain amount of respect for an animal.

Before long, Nakia spots oneof the Zara Coast's

most graceful animals.

A reef manta ray appears from the gloom.

Soon several rays circle the team.

We're very very lucky with our mantas.

They're very, very curious.

They come extremely close so itmakes it very easy for us to get

some nice identification photos.

Nakia takes photos of the spot patterns

on the manta ray's belly to ID the animal.

She uses a laser to measure its size.

They swim over you, they swim with you,

it's breathtaking and it will never get old, ever.

It's wonderful.

The mantas have come here to be cleaned.

Mozambique's manta rays form partnerships

with eight different species of cleaner fish.

The cleaners remove parasites,

mucus and dead skin from the manta ray's body.

Each fish cleans a different area

so they don't compete with each other.

But on this reef, the sergeant major damselfish outnumber

the other cleaners.

The rays can spend as long as 10 hours

interacting with the cleaners.

Mantas have the largest brain of any fish in the ocean.

Specifically, the regions of the brain responsible

for sensory functions, memory and learning.

Behavior in this researchfootage suggests that manta rays

signal to the fish the body parts they want cleaned.

They flick the back of their pectoral fins

or flare their gills to indicatethese areas require

immediate attention.

On this reef, one manta ray demands more attention

than the rest.

This female reef manta bears a scar from a shark bite

on her pectoral fin.

A damselfish follows closely behind her to clean the wound.

The ray's bloated stomach showsshe's pregnant.

She will need to be cautious inthese waters.

With the mantas you do see alot of predator scars

on their pectoral fins.

This is usually from bigger shark species,

Zambezi sharks, blacktip sharks,

lot of different shark species that could

potentially be preying on the mantas

so we do see a lot of the mantas

with these big chunks taken out of them.

The manta isn't typically a target for large predators.

Nearly 3,000 miles east of Mozambique,

the Maldives has one of the world's largest

reef manta populations.

Yet relatively few are attacked there.

In an estimated population ofmore than 5,000 reef manta rays

only 500 exhibit any sign of bite marks or scarring,

about 10% of the population.

The manta ray's size alone isenough to deter most attackers.

But in Mozambican waters morethan 70% of the reef manta rays

have visible scars.

The direct result of shark attacks.

While we don't always see these large predatory sharks

while we're out on our surveys,

we tend to see some remnants that they're there.

As Nakia and her team survey the area,

they come across an unexpected find.

A half-eaten blacktip shark.

It's a little eerie, bad visibility,

this looks like it didn't happen too, too long ago

so you're wondering if these sharks

are still looming in the area.

I was very curious as to what could've taken

half of this shark in a clean swipe.

The size and shape of the bite mark

suggests a much largerpredatory shark is responsible.

There's no sure way to determine which shark actually did take

the chunk out of the blacktip,

however, this nice clean cut andthe blacktip was quite big,

we are assuming that it was a white shark or a Zambezi,

one of these bigger sharks in our area.

Researchers believe that Zambezi sharks

are the primary predators in these waters.

Also known as Bull Sharks.

These predators are consideredto be one of the most dangerous

sharks in the world.

They're fast, agile and will eatalmost anything.

Bull sharks are opportunistic hunters.

Though they prefer smallerfish like snapper and mackerel.

They will eat what's readily available.

Bull sharks have been known to attack rays, dolphins.

Even other sharks.

They prefer to hunt in murky waters.

And Mozambique's plankton-fuelled coast

fits the bill.

For this soon-to-be mother, the worst is over.

A manta ray's tissue regenerates incredibly fast.

With a little help from the damselfish

the wound remains clean

and should heal completely in a few weeks.

Meanwhile in Tofo, Andrea and Anna continue their search.

But there are no smalleye rays in sight.

Not even a single manta ray.

In the distance, Andrea spots ablotched fantail ray.

Also known as a marble ray or its distinctive light-and-dark

blotched colouration.

These rays are found throughoutthe Indo-West Pacific

in a wide variety of habitats from reefs to shallow lagoons.

The ray moves its disc-like pectoral fin

to cruise through the water.

The marble ray can grow to six feet in width.

The blotched fantail ray isn't aggressive.

But it's cautious of strangers in the water.

The ray assumes a defensive position.

It's just amazing how you can't get close to them at all

without them starting to posture.

The smaller the ray the morefrightened they are of a large,

strange animal.

The ray's stinger sits near the base of its tail

and contains a sharp spine

with serrated edgesthat face the body of the fish.

Its greatest weapon, a venomous gland

rests at the base of the spine.

A membrane-like sheath covers the entire stinging mechanism.

Anna approaches carefully to geta photo ID of the stingray.

When a ray strikes, its tail shoots up,

jamming its stinger into the body of its victim.

The pressure from the strike tears the protective sheath.

The sharp, serrated edges of thespine sink in.

And an excruciating venom flowsinto the wound.

If released into a vital organ, the venom can kill a human.

These bottom-dwelling hunters often hide in the sand

and go unnoticed by divers.

If stepped on, the ray's sting usually leaves a wound

around the ankle.

It's a treatable injury if it'slooked after quickly enough.

The smalleye stingray is far larger in size

and its tail is much more robust.

So it could be more dangerous.

But there are no recorded incidents

with this rare and elusive animal.

Over millennia, the giant oceanic manta ray

lost its stinger entirely.

Its size alone is enough to keepmost predators at bay.

A small bump on the back of itstail serves as a reminder

of the time this large fish had a stinger.

Another day breaks in Tofo.

And Andrea and her team get a second chance

at finding the smalleye stingray.

They prep the research boat as the hunt presses on.

But a new challenge lies ahead.

The sea's actually really flattened out today

which is amazing!

It's gonna be a great ride out there, much flatter.

We have a little bit of a tricky launch,

even though there's no waves, there's a massive sandbank

so I'm actually going to have to launch sideways

which is pretty strange and track along the coast

and then spin out just around the sand bank.

We'll see how that goes.

I don't normally launch like that here

but this sort of sand bank popped up

so we'll see how it goes.

Everyday is something new here so a little bit of a challenge

but we'll see.

Andrea steers the boat clearof the sandbank

and the team heads out.

Hopeful that the flatter seas will yield better visibility

and allow them to spot the smalleye.

The visibility is much better today

providing a much better view of the sea life.

Unfortunately the better visibility

also reveals a disappointing reality.

The larger animals just aren't there.

Not seeing one of the most rare animals in the ocean,

the smalleye, isn't surprising.

But not seeing manta rays off Tofo's coast, is.

We were chasing the good vis today.

I'm guessing maybe all the animals are hiding

down in the green water down south.

We're gonna brave it tomorrow and go all the way south

to some of the sort of flagship reefs here.

It might be cold, it might be green

but we're still hoping for a lot of animal life.

In the last few days we haven'treally seen very many animals,

which is kind of rare.

How do you hide some of the world's largest fish?

You know, where do they go?

The lack of sightings over the last several days

reveals a sobering truth

about Mozambique's manta ray population.

It's indicative of the fact that the populations are crashing.

Mantas, we used to encounter them 80, 90%

of the time we go diving and now sometimes it's 30%

of the time that we go diving.

We've lost a lot of our animals here

so it's not as easy to have encounters

with these giants anymore.

Andrea's concerned about hermanta ray population

but she must press on with the task at hand.

Locating the smalleye stingraysthat come here seasonally.

Today Andrea's team will head south to continue the search.

The visibility underwater will be poor,

so finding the animals will be harder.

But for researcher, Claire Prebble,

the murky conditions here in Tofo are an advantage.

Cloudy water is often created by nutrients.

Plankton, the tiny plant and animal-based organisms,

that drift on the ocean's current use these nutrients,

along with sunlight, to grow.

Plankton is the main food source of the animal

Claire hopes to sight today: the whale shark.

One of the first and mostimportant pieces of information

we like to get about the whale sharks

is actually their identity.

So the way that we do this is through a technique

called photo identification.

The spots and stripes make a wonderful fingerprint

really for us to be able to identify individual sharks.

The ID area is here

so we take a photograph behind the gills

and next to the pectoral fin inthis sort of square box here

just before it gets to the ridges.

At the moment in Mozambique we have identified 665 sharks.

We have a good idea of what thewhale sharks are doing

when they are close to this coastline.

So the information that we're lacking at the moment

is what these animals are doing

and where they're spending their time

when they're away from this coastal aggregation site.

By looking at their diet, looking at their tissues,

we can find out what they're eating, and from that

we can also find out where they're eating.

We do a couple of differenttypes of analyses on this tissue

and it's based on a you are what you eat' principle.

As the whale sharks go through their life they

will swim into different areas

and they will eat different things

and this biochemical analysis we do

is just taking advantage of this tissue passport

that the whale sharks have created unknowingly

in their skin and we can almost reverse engineer

what they've been doing and

where they've been going from this.

To collect a sample, researchers poke the whale shark

with a pole spear rigged with a biopsy tip.

They target an area near the dorsal fin.

Where the animal's skin is thickest.

And the density of nerve endings is lowest.

This ensures the animal doesn't suffer

It's likely the whale shark doesn't even feel the poke.

As the team heads out, Claire looks for whale sharks.

But spotting them is no easy feat along this coastline.

The whale sharks don't spend very much time

very close to the surface.

So, we're really just looking for a suspicious

shark-looking shadow underwater.

So far, no whale sharks.

So turns her attention to another, less glamorous,

area of research.

Zooplankton are tiny aquatic animals,

no larger than a grain of rice.

From copepods, to crustacean and snail larvae,

these tiny creatures drift in the water

nourishing ocean filter feeders small and large.

Zooplankton is a favorite food of whale sharks.

These tiny animals could be the reason

that the resident population of whale sharks

remains along this coastline.

Without a microscope,

Zooplankton are nearly invisible.

Claire sieves the water out.

If the tissue sample from the whale shark

matches these plankton samples

it will prove that Claire's sharks do in fact

feed along this coastline.

The diet of a jellyfish

is similar to that of a whale shark.

Both feed on tiny plankton thatdrift in the water.

Jellyfish are short-lived creatures.

They're also poor swimmers,

and rely largely on the current for transportation.

Making them a good representative

of the local food web.

Claire jumps in to grab a sample.

She wears gloves, to prevent a painful jellyfish sting.

What I like to do is take a bit of the bell,

so around the edge of the domed part of the jellyfish,

I only need a small tissue sample.

Andrea and Anna are hopeful the plankton in these murky waters

will invite some megafauna.

And it has, but not in the way they hoped.

We're on our way to a dive site now and we actually see

the locals cutting up somereally big animal on the beach.

So I'm assuming it's a manta ray.

We see a big gill net behindthem so it's obviously an animal

that's probably run into a gill net

as it happens along this coast.

We've lost a lot of our mantas as a result of that,

a lot of our other megafauna

so it's really important for us to get an understanding of,

you know, what's being caught,

how it's being caught and where.

Let's go!

Waves coming!

So Andrea and Anna and Claire decided to swim through

the waves to go and see what it is,

before they chop it up and it's unidentifiable.

I'm just gonna quickly fly the drone

to get some evidence and also to get a picture.

Photo and video evidence of this incident is crucial

for Andrea and her team

to convince the Mozambique government

of the need for manta protectionalong this coastline.

They head in for a closer look and to collect specimens

from the dead ray.

The death of a mature female manta ray is a huge loss.

Most females don't reach sexual maturity

until they are 10 years old.

It's assumed that a healthy mother,

gives birth to just one pup every 2-5 years

throughout her lifetime.

Which is thought to be 40 years.

It's a big problem for these large animals

because they reproduce so slowly

that they cannot withstand any sort of fishing pressure.

By far the biggest threat to ourmarine megafauna here

are gill nets.

Gill nets are set up by many different groups of people

and villages up and down this entire coastline.

And they're set perpendicular to the coast

so as these animals travel up and down

this stretch of water that they're utilizing,

they'll run straight into these gill nets.

And the fishermen might belooking for smaller fish to eat

for dinner but if they catch a manta, most of these people,

they're hungry, they don't have many options

and they're going to eat whatever swims into that net.

The manta ray is now completely chopped to pieces.

This is a meal for an entire village.

For Andrea and Anna it's a tragedy.

I've established such a close connection to these animals.

They're not just mantas for me anymore,

I want to know who it is.

I want to know which manta's gone.

She scours the beach in search of any body part with spots.

Anything she can piece togetherto identify this manta ray.

But it's hopeless.

It's like finding a friend.

But at the same time, you know,

I think it's really important to try and rise above

that a bit and try to get a positive out of a negative.

Andrea and her team are ableto take samples from the manta ray

that will advance their research.

Luckily we were able tosecure almost all of the samples

we wanted.

So we are able to do a lot of science

even though it's obviously a really sad thing to see.

With heavy hearts, the team heads back to shore.

Down at Zara, Nakia and her team

encounter a sobering reality of their own.

Just as we were finished launching the boat we were on our way

just beyond the breakers and a local fisherman came to us

and he said he has a problem.

We got ready to go assess the situation.

A leatherback turtle's been caught in a gill net.

I think it's a leatherback turtle?

It's a big leatherback on the net, big one.

It's a big leatherback, it's getting drowned.

I was in a state of mind of just get in the water,

get this turtle cut out, let itfree, no matter what happens,

no matter the conditions just dive down.

When a turtle is in distress

they have a range of about a few minutes of surviving time

cause they lose oxygen when they're stressed.

Very big turtle and it's a really rare turtle to see.

I haven't seen a leatherback right close to the beach,

so this is my first time.

The team only has 10 minutesto save this endangered turtle.

Nakia holds the leatherback still for Mornay.

I'm just cutting the net off,

trying to free this turtle as quick as possible

but at the same time not cutting off parts

that will make it swim away with netting around the neck

or the flippers.

I don't know what's gonna happen with the guys in the water now

so Pedro can we go closer to seewhat's happening please.

The turtle swims off buta piece of netting

is still tangled around her fin.

Mornay chases after her.

Finally, the team can breathe asigh of relief.

She is free.

It was entangled very, very badly

and luckily we were there to rescue it

but had we not been there, you know,

it probably would have drowned.

And it's sad to see these larger animals get entangled

and die just at thecost of these fishing practices.

It's not only one net, youcan see it, it's a lot of buoys.

We have like 7, 10 nets at the same place...

so it's quite, it's quite dangerous.

They caught a big mantas and big rays

a lot of rays and sharks and stuff.

It's not legal, but yeah, our government tried to stop

but it's the local people, this is their food source.

Back in Tofo, Claire freezesher plankton and jellyfish samples

to be sent off for analysis.

Once I've analyzed all of thedata this is the kind of graph

that I get.

An overlap between the bluedots belonging to the whale sharks

and the red dots belonging to other plankton-eating animals

will prove that that the whale sharks come here specifically

to feed on the plankton.

What I'll be looking for withthe data in Mozambique

is whether the whale sharks fallvery close and very nicely

within the species that we sample from this coastline.

Andrea's research, is a little messier.

We just got back from the boat and I'm trying to rush to get

some of these samples processed.

Obviously nobody wants to see mantas get killed

so we're trying to make something good out of a bad situation.

We got a bunch of things from the manta:

we got a bit of the jaw, so we can have a look at the teeth.

The gill raker, that's actuallywhat people kill mantas for

is literally for the gill rakersto trade for Chinese tonics.

We got a piece of liver, I meanjust endless amounts

of little bits we got from the manta.

Very few biologists have the opportunity to be able to

dissect mantas and collect parts from them.

It's one of the biggest issues of trying to describe species

is you actually don't have access to dead specimens.

In order to document a species you actually have to look

at everything from their teeth to their skin to their gills.

In the early days I used to getquite upset and emotional and

now you have to just try and think to yourself that manta's

already gone, what can we get from this?

You know what information can we get from the locals

to understand their perspective.

What information can we get fromthe animals that can help

further science, that we can figure out how to stop this,

and that's what we did today.

It was very much business, we went in,

we talked to the fishermen,

collected our samples and we left.

Later tonight I might have a drink to that manta

but you know at the moment we're still processing

those samples and trying to get as much as we can

so that wasn't a wasted life.

The next several days yield no sightings of smalleye stingrays.

And, more concerningly, no manta rays.

With smalleye stingrays, ourstudies are so new with them

we can't really give much good information on whether

the population is increasing or decreasing.

They are something that's quite uncommon to see

which is why we reallyhave to integrate their research

in opportunistically when we're studying mantas

because the mantas have historically been much

more consistent in this area

whereas smalleyes show up less frequently.

Three days after the camera crew left,

a Marine Megafauna researcher

filmed this sighting of a smalleye stingray.

One of the ocean's most rare animals has been seen.

But this coastline's most frequent visitors,

the manta rays are nowhere to be found.

Highlighting the problem.

We've seen more than 88% decline in sightings,

which is the largest decline onrecord anywhere in the world.

That's huge.

A lot of that is due to fishing.

From Tofo beach, to Zara Bay,

the coast of Mozambique is under pressure.

Gill nets snare the marine giants

that call this coastline home.

But the researchers that live here will stop at nothing

to protect them.

It got under my skin this place, these animals.

I'm really committed to this coastline now.

This is still my home and I won't leave until

I see this population is protected.

We recently increased our conservation outreach

into the local communities...

working with local fishing collectives and co-operatives

to implement more sustainable fishing methods

and really have them manage their own resources.

Researchers here in Mozambique

are targeting the creation of marine-protected areas

and the way that we're doingthat is we're trying to isolate

what are the most important critical habitats

along this coastline so that we can figure out

how to protect them first.

The manta rays use a very close reef as a cleaning station,

turtles are using our beaches to nest on

so protecting these areas is very important

in order to keep these species from declining

any more than they already are.

The ocean really supports the life on this planet

and so we don't really have a choice

but to fix some of these issues.

Hopefully we can build a chain of parks along the coastline,

maybe even connect those areas so that

we can have a large enough marine-protected area.

It's only by working together that we're going to figure out

how to save the ocean.

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