They're one of the largest animals in the ocean.

Certainly they're the largest of any of the ray species.

They can get up to about 25 feet across.

When they come towards you and they're that size,

they look like an alien spacecraft as they go overhead.

They actually block out the sun.

It's just so incredible to be that close to such

a large animal, especially one that you don't have to fear.

My name's Andrea Marshall.

I'm a manta ray researcher and a marine biologist.

I've been in love with the ocean all of my life.

Ever since I could remember, I wanted to be

a marine biologist.

When I moved out to Africa with the intention

of studying things like great white sharks,

I actually shifted my focus over to manta rays

when I realized that no one had ever done

a study on manta rays before.

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One of the things that makes manta rays so special is

that they're large and sometimes people feel frightened

by them just because of their sheer size,

but actually they're one of the most gentle animals

in the entire ocean.

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Manta rays are very intelligent animal.

They actually have the largest brain of any marine fish,

but one of the things that surprises me the most is

just the fact that they seek out encounters with humans.

So this isn't an animal that swims away from you,

this is an animal that swims to you.

They recognize you almost as a friend.

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Southern Mozambique is just an incredible location.

I've lived here for the last 15 years

and even though I travel all over the world

to do my work, I enjoy coming back here

because this is such a wild place.

It's so exciting.

One of the reasons I began work on mantas is

because I knew that these animals were under threat.

Recently you know within the last 15 to 20 years,

they have started to be fished for Asian tonics

and as a result of this, we've seen manta populations

crashing across the globe.

Even here in Mozambique where we don't even have

a very aggressive fishery, we've seen

the population collapse by up to about 98%

over the last 15 years.

We're starting to lose them faster

than we can study them.

So it's really important for me to get

these messages across to people

who don't have the opportunity to peak down

into the underwater world.

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