You're listening to shortwave from NPR.

It was 2016 in the Florida Keys and a little species of endangered deer called the key

deer weren't acting right.

People just start noticing that these deer seem to be having these wounds on their heads.

That's Sarah Zhang, a reporter with the Atlantic.

She says the deer looked like they'd been injured by something.

There were gashes on their heads.

They were kind of like walking out the street, like really shaking their heads and they're

trying to shake something off.

Warning right here.

It is about to get gross, like real gross.

Kim Gabel is a big pine key resident and has seen the deer in her area.

You'll see gaping holes or wounds in their neck or in their head and you'll see them shaking

their head.

You would see a deer like almost half its head would be missing and you could see down

to the skull.

And eventually these deer start dying and you know it becomes kind of this big mystery

of why are they dying especially with these really really awful wounds on their heads.

Local scientists looked into it and eventually tests confirmed the deer were infected with

a parasite.

Its scientific name is C. Aminivorex, which means man-eater.

It's more commonly known as the screw worm.

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