How Vultures Can Eat Rotten Meat

How Vultures Can Eat Rotten Meat

Posted: November 5, 2015

When your primary food source is festering meat, acid, poop, and bacteria become some of your best friends.

I’m Anna Rothschild, and this is Gross Science.

Vultures are meat-eating scavengers. That means that they don’t kill their own prey—instead they wait for another animal to make a kill, and then chow down on the leftovers.

The thing is, rotten meat can have harmful bacteria on it, like pathogens that cause food poisoning, or even anthrax. If you or I ate those microbes, we’d be in big trouble. But vultures don’t seem to care. They’ll actually go a disgusting step further. To get at the fleshy goodness inside a rotting carcass, they’ll peck in at the animal’s softest spots, like the anus, inadvertently scooping up feces along with the bacteria-ridden meat.

So, how do vultures cope? Well, they have incredibly acidic stomachs, which help them to digest bone and kill diseases like anthrax. They’ve also evolved either immunity or at least a level of tolerance for certain types of bacterial toxins. In fact, their intestines are naturally colonized by species of bacteria that are related to disease-causing ones typically found on rotting meat.

On top of that, some vultures poop on their legs. This is a behavior called urohydrosis, and typically birds do it to cool down since they don’t sweat. But scientists think the poop may also have antimicrobial properties, and could help clean their legs. Cleanliness is also one hypothesis for why vultures are bald. Feathers on their neck and head would only make it easier for bacteria to stick to them.

But vultures aren’t immune to everything. While they might not fall victim to the same diseases we do, certain medications given to livestock are actually poisonous to vultures, putting these guys at risk.

And, because of their unique ability to clean up disease-ridden carcasses, and keep other scavengers in check, vultures would be a terrible thing to lose.

Ew.

PRODUCTION CREDITS

Host, Animator, Editor

Anna Rothschild

Writers

Elizabeth Gillis and Anna Rothschild

DP, Sound

Elizabeth Gillis

Bye Bye Buddy

Music Provided by APM

IMAGES AND VIDEO

Original Footage

©WGBH Educational Foundation 2015

Vultures Eating Zebra

Courtesy Dan Fagin

Gyps fulvus 02

Wikimedia Commons/H. Zell

SFX

Cockroaches

Freesound/StateAardvark­
(used with permission from author)

Squeak Pack/squeak_10

Freesound/Corsica_S

Jelly Mangling on a Plate

Freesound/lolamadeus

Projector Screen Pull In Out

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Wink

Freesound/bennychico11

Produced by WGBH for PBS Digital Studios

POSTER IMAGE

Gyps fulvus 02

Wikimedia Commons/H. Zell

Want more info?

Vulture microbiome paper:
http://www.nature.com/ncomms/2014/141125/ncomms6498/full/ncomms6498.html

Hawk Mountain Sanctuary Association:
http://www.hawkmountain.org/