Why Don't Vultures Eat Live Prey?

iStock / iStock

Why do vultures not take live prey? They are huge and have sharp talons and bills. They are excellent flyers and can soar to great heights. They have whatever it takes to be superb predators, however they seldom take live prey. Why?
Stefan Pociask:

Here is the infamous folk drawing that started it all, and spawned posters, T-shirts, patches, and hundreds of memes, well before the internet even existed. It was drawn in Bismark, North Dakota in 1973, but no one knows the artist to attribute it to. “Patience my ass … I’m gonna kill something!!”

It’s funny and ironic, but the truth is, a vulture would never say that. They are, as we all know, “nature’s garbage men,” or, to be more PC, "nature’s sanitation engineers." So, why don’t they kill something? Why bother? Just like undertakers have the world’s most secure job, vultures have the world’s most secure food source. A healthy vulture will never go hungry. The two things you can never avoid are taxes and death. The government takes advantage of the former; vultures take advantage of the latter. They fill a truly vital ecological niche on the planet. We need them. They have evolved to be specialists in their occupations. Without vultures, I doubt the world would survive 100 years before most vertebrates were wiped out. They keep disease in check. Let me point out that I’m referring to areas where vultures were present, but then were eliminated or reduced. Ecosystems that never had vultures have their own established way of dealing with things, through other means.

A vulture’s digestive tract can easily handle bubonic plague, rabies, distemper, anthrax, and most all other evil, little, biological nasties that threaten other forms of life on Earth. It’s all good to them. How can they do this? It’s complex. But basically, their digestive tract has two tools it uses: One is a very low Ph in their digestive juices. It is so corrosive that if a vulture eats meat that contains lead bullets, it will dissolve the lead and give the vulture lead poisoning. That is their Achilles’ heel. A poisoned vulture usually means lead poisoning and is one of the biggest threats to vultures.

Of course, lead bullets are a manmade invention so, once again, hurray for mankind for finding a way to poison the unpoisonable. But besides that, up to 60 percent of toxic bacteria is simply dissolved. Bye-bye deadly microorganisms. The other tool that vultures have is that the remaining 40 percent of toxic bacteria that isn’t destroyed just hangs out in a vulture’s gut, doing nothing. Vultures are cool with that. No biggie. It’s got to be pretty frustrating for the toxic microorganisms, who are used to getting their way. But vultures are simply not affected.

They have some other features that help them with this. You’ve probably heard that the reason their heads are featherless is so that they can freely stick their heads into the nastiest of stink-holes, and not worry about getting their feathers all contaminated. That’s true. They stay cleaner that way. The sun and rain wash away extraneous filth. It comes in handy. Also, they have a way to disinfect their feet, which are always walking on top of putridness. In another irony, to cleanse their feet, they simply defecate on them ... quite regularly. The uric acid is so strong, it kills whatever is on their legs and feet (and it also keeps them cool). All these things make them excellent at staying healthy, despite what they eat.

Now the original question asked noted, “They are huge and have sharp talons and bills.” That’s not exactly true. Let me explain it this way: When I first started working as a Raptor Rehabber, I was introduced to all types of raptors—including eagles, hawks, owls, osprey, and vultures. I had to learn how to handle and hold these large vicious birds. They all have large, sharp beaks, as we know. Understandably, I was concerned about getting bitten by any of these birds. It wasn’t long before I learned something quite surprising. All these beaks, even an eagle’s beak, are the least of my concerns:

Even this guy really isn’t going to hurt me with his beak. I’ve been bitten by raptors more times than I can count. No big deal, other than the occasional pinch, when they get you just right. No, beaks of most raptors are not a problem. The problem is these:

These are sharp talons. This is an osprey, which is very dangerous to handle. Osprey and most all raptors use them to hunt live prey. On the other hand, these are the talons of a vulture:

These feet are the 90-pound weaklings of the raptor world. They are like chicken feet. Not sharp, the talons are not long, not strong. A vulture can’t grab with them. Guess what he uses them for. I’ll tell you: walking! Imagine that! Yep, just for walking. They are not weapons. So vultures can’t kill live prey with them, or even grab it. But they can walk and balance a heck of a lot better than an osprey, with those long sharp talons. So, when I handle most raptors, the feet must be controlled because they can do serious damage. But with vultures, it’s not a worry at all.

On the other hand, whereas beaks of most raptors are not a concern, the beak of a vulture most definitely is. Look at this:

And this is just a tiny baby! (I love this picture. I call it “I am Vulture! Hear me Roar!”) Beaks are long, big, sharp, and strong. They use them to tear apart large dead animals like wolves, lions, elephants, etc. I was once carrying a Black Vulture against my chest, trying to control his head. I slipped up, he spun his long neck around, and slashed out at my eye! I had a long deep scar just a half-inch below my eye for quite a while. So they are nothing to mess with. But a vulture can’t kill live prey with his strong beak because he’d first have to catch it with his chicken feet. And that’s not going to happen.

So there you go. Vultures are very specialized. They eat dead animals and they are very good at it. But they generally don’t hunt them. They are very good at finding dead animals. A Turkey Vulture has one of the most amazing senses of smell in the animal world. They can smell a rotting carcass from thousands of feet in the air. And here’s something interesting: the Black Vulture, a close relative, is nearly always hanging out with a Turkey Vulture (red headed vultures). Black Vultures can hardly smell at all. So what they do is, they soar up in the sky a few hundred feet above the Turkey Vulture. And when the Turkey Vulture smells a meal, they follow him down and take it from him. The Black Vultures are the more aggressive of the two. So the Turkey Vulture, after finding food, has to share his meal, and sometimes even wait until the others are done. He doesn’t seem to mind though. Black vultures act as protectors. They have a strange but stable relationship that way.

Vultures are very important, but they aren’t killers. We call them ugly, but even a vulture is cute when he’s little and fluffy. Here’s a video of me feeding a brood of little vulture chicks. A little messy ... but who among us can say we haven’t had our faces covered in chunks of raw meat?

Yes, that’s me wearing camo, so that they don’t recognize me as a human. They are the most impressionable of all birds when young. Very smart. We don’t want them thinking man is where they get their food. I don’t want them believing I’m the mama. So I cover up, don’t talk to them, and use this adult vulture puppet to feed them until they can be set free.

Now here’s the bad news. Certain populations dropped drastically over the past three decades from as many as 90 million to only 10,000 today, making them critically endangered worldwide. Most species are endangered. Some species are better off.

There are a few reasons why this magnificent bird could be close to disappearing. In 2003, scientists identified diclofenac, an anti-inflammatory drug used to treat livestock, as the main cause for this decline. So, when cattle treated with diclofenac die and the vultures feed on them, the medicines work their way into the vulture's body system, causing renal failure. Vultures don't have a certain enzyme that can break down diclofenac and therefore it hits their kidney dangerously. Vultures eating the carcasses of animals recently treated with the drug die from severe kidney failure within weeks of ingesting it.

Then there’s the rampant lead poisoning killing many more.

Plus, many people shoot them. Please help people understand they are vital and endangered. This is no joke. They could soon be gone.

In the 1990s, India lost 95 percent of their vultures. Following the decline of vultures, India experienced a strong uptick in feral dogs—by an estimated 7 million. The increase in dogs, feeding on disease-ridden carcasses, is thought to have at least partially caused a rabies outbreak that was estimated to have killed 48,000 people from 1992 to 2006 in India—deaths that may have been avoided if not for the disappearance of vultures. Vultures can eat any disease that shows up on a carcass. Many of those diseases are deadly to various other vertebrates. But since the vultures get there first and consume the disease-ridden flesh or eat it before a disease takes hold, or before some insect infects it, they have just prevented the spreading of any number or diseases. Insects become carriers. Other animals that have more contact with humans and other mammals get infected by those animals become carriers, and it just spreads. The number of diseases that can result from rotting carcasses is immense.

Meat doesn’t have to be rotting to putridity to become diseased. Many animals are scavengers and will eat flesh they don’t know is diseased. Rats are one classic example. And many of those animals die. They, in turn, are eaten by more animals, further spreading the disease, and so on. And/or more insects spread the disease. That’s how epidemics happen.

So: Save a Vulture, Save the World

This post originally appeared on Quora. Click here to view.