Vultures: the acid-puking, plague-busting heroes of the ecosystem - Kenny Coogan

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In the African grasslands, a gazelle suffering from tuberculosis takes its last breath. The animal's corpse threatens to infect the water, but for the vulture, this isn't a problem: it's a feast. With a stomach of steel that can digest diseased meat and waste, vultures are essential to removing dangerous pathogens from ecosystems. Kenny Coogan explores the importance of the desert's cleanup crew.

Lesson by Kenny Coogan, directed by Katarina Jukić.

In the grasslands of Mauritania,

a gazelle suffering from tuberculosis
takes its last breath.

Collapsing near a small pool,

the animal’s corpse
threatens to infect the water.

But for the desert’s cleanup crew,
this body isn’t a problem: it’s a feast.

Weighing up to 10 kilograms

and possessing a wingspan
of nearly 3 meters,

the lappet-faced vulture
is the undisputed king of the carcass.

This bird’s powerful beak and strong neck

easily tear through tough hide
and muscle tissue,

opening entry points
for weaker vultures to dig in.

This colossal competition is too dangerous
for the tiny Egyptian vulture.

With a wingspan of only 180 centimeters,

this vulture migrated to Africa
from his family nest in Portugal,

using thermal updrafts to stay aloft
for hours at a time.

But upon arrival, he finds himself near
the bottom of the pecking order.

Fortunately, what he lacks in size,
he makes up for in intelligence.

A short distance away,
he spots an unguarded ostrich nest,

full of immense, but impenetrable eggs.

Using a large rock, he smashes one open
for a well-earned meal—

though he’ll circle back to the gazelle
once the larger birds are gone.

High above the commotion
are Ruppell’s Griffon vultures.

Soaring at an altitude
of over 11,000 meters,

these birds fly higher
than any other animal.

At this height, they can’t see
individual carcasses.

But the sight of their fellow vultures
guides them to the feeding.

Their featherless heads help them regulate

the sudden rise in temperature
as they descend—

and keep them clean
as they tear into the decaying gazelle.

The carcass is stripped clean in hours,

well before the rotting meat
infects the water supply.

And the tuberculosis doesn’t
stand a chance at infecting the vultures.

These birds have evolved the lowest
gastric pH in the animal kingdom,

allowing them to digest diseased
carrion and waste without becoming sick.

In fact, species like
the mountain-dwelling bearded vulture

have stomachs so acidic,

they can digest most bones
in just 24 hours.

This adaptation helps smaller vultures
supplement their diet with dung,

while larger vultures can consume
diseased meat up to 3 days old.

Their acidic stomachs protect them
from living animals too:

their rancid vomit
scares off most predators.

These stomachs of steel are essential
to removing pathogens like cholera,

anthrax, and rabies
from the African ecosystem.

But while vultures can easily digest
natural waste,

man-made chemicals are another story.

Diclofenac, a common veterinary drug
used to treat cattle in India,

is fatal to vultures.

And because local religious beliefs
prohibit eating beef,

scavengers often consume cattle carcasses.

Since the 1990s, the drug,

along with threats from electricity pylons
and habitat loss,

has contributed to a 95% decline
in the region’s vulture population.

In nearby Africa,
poachers intentionally poison carcasses

to prevent the birds’ presence from
alerting authorities to their location.

One poisoned carcass can kill
over 500 vultures.

Today, more than 50% of all vulture
species are endangered.

In regions where vultures
have gone extinct,

corpses take three times longer to decay.

These carcasses contaminate
drinking water,

while feral dogs and rats carry
the diseases into human communities.

The Asian and African Vulture Crisis
has led to an epidemic of rabies in India,

where infections kill roughly
20,000 people each year.

Fortunately, some communities have already
realized how important vultures are.

Conservationists have successfully banned
drugs like Diclofenac,

while other researchers are working
to repopulate vulture communities

through breeding programs.

Some regions have even opened
vulture restaurants

where farmers safely dispose
of drug-free livestock.

With help, vultures will be able
to continue their role

conserving the health of our planet—
transforming death and decay into life.