30 Animals You Don’t Want to Mess With

Arachnophobia. Entomophobia. Ophidiophobia. If you didn’t have a fear of spiders, insects or snakes before, you will after learning they’re some of the most dangerous animals on the planet. Some are isolated, like Komodo dragons, which are found only in Indonesia. But others, like the bull shark, are much more widespread. Either way, these animals represent the very deadliest that Mother Nature has to offer.  

Cape Buffalo

Weighing anywhere from 600 pounds to well over a ton, the cape buffalo is one of the most dangerous species on the African continent. Their status at the very top of the food chain means they have few natural enemies, and these unpredictable animals are known to kill or maim hundreds of people every year.

What makes this particular species, also known as an African buffalo, so dangerous – and therefore so desirable for trophy hunters? Their horns, which fully fuse together at around five or six years of age, are a built-in battering ram, and their massive size and weight can overcome almost any predator. They’re also highly vocal creatures who will attack as a herd, overwhelming even the most cunning of animals. 

Box Jellyfish

Box jellyfish are beautiful to look at, with their translucent bodies and wispy tentacles gliding through the water. Out of the dozens of species of box jellyfish known to man, most won’t harm you if they brush up against you in the water, but there are several whose venom is potent enough to make you sick (or even kill you).

The three most dangerous sub-species of the box jellyfish are the “hub” jellyfish, found mainly in the coastal waters of Japan. the tiny Irukandji, which actively hunt prey in the waters of northern Australia, and carukia barnesi, another highly venomous Australian jellyfish. Even the smallest amount of their venom can cause dizziness, nausea, difficulty breathing and body pain. 

Cone Snail

Wait a minute, you’re saying snails are dangerous? Well, not all of them; your average garden variety snail is as harmless as a butterfly. We’re talking cone snails, which refers to a group of venomous, carnivorous and predatory tropical marine snails (also known as gastropods) that come in all kinds of sizes, shapes and colors.

In general, the bigger the cone, the more venomous the snail. The larger ones actually hunt small fish, while smaller snails snack on micro-organisms and all manner of aquatic worms. They paralyze their prey and inject their venom via a needle-like extension that is barbed to better catch on to their victim. Some venoms are quite mild while others can be fatal.

Pufferfish

Found mostly in tropical waters, pufferfish have developed a unique natural defense that helps compensate for how slow they are in the water – they’re highly toxic. The level of toxicity can vary from species to species, and even where the poison is held can differ. Scientists have found venom in the liver, ovaries and even in the skin itself of certain puffers.

Despite how dangerous it can be eaten, pufferfish is considered a delicacy in Japan and several other countries. It takes a highly trained chef to be able to successful remove the venomous parts of the fish and correctly prepare it for consumption. Every year, there’s at least a few deaths due to incorrectly prepared pufferfish.  

Golden Poison Frog

These brightly colored frogs may look all innocent just hanging out in tropical rainforests, but their skin is covered in a highly toxic poison that deadens its victims’ nerves and can lead to heart failure and death. It’s their natural defense mechanism for an environment in which they’re at the lower end of the food chain.

The golden poison frog comes in a variety of colors, including green and pink, with yellow being the most common. Many indigenous cultures use the concentrated poison as a hunting weapon, dabbing it onto the tips of their spears and arrows. The frogs themselves are immune to it, and hunt for prey using their exceptionally long tongues. 

Black Mamba

There’s a reason assassin Beatrix Kiddo, played by Uma Thurman in Quentin Tarantino’s bloody revenge film Kill Bill, goes by the code name “Black Mamba;” she’s the deadliest hitwoman on the team. The black mamba, which is native to sub-Saharan Africa, is incredibly lethal, second only to the king cobra in terms of size.

It has few natural predators, and is equally comfortable high up in the trees or gliding across the dry desert floor, where they can reach short distance speeds up to 10 mph. Their venom is comprised of mostly neurotoxins, which can induce symptoms like blurred vision, vertigo and respiratory paralysis in as little as 10 minutes. One good thing about the black mamba is that it only attacks when it feels cornered or threatened, so be sure to keep your distance.

Mosquito

Sure, you probably think mosquitos as more annoying than anything, but these buzzy, blood-sucking insects are actually one of the deadliest creatures on the planet. They kill more than 700,000 people a year through the spread of infectious diseases like West Nile virus, dengue fever, malaria and yellow fever.

They’re especially dangerous in areas where fresh running water isn’t always available, since the females lay their eggs in stagnant water. And, in addition to the diseases mosquitoes spread, their saliva can induce an allergic reaction in some people that can range from mild discomfort to severe shock.

Saltwater Crocodile

The saltwater crocodile is one of the largest crocodiles in the world, and an incredibly dangerous predator that ambushes its prey and swallows it whole. But that hasn’t stopped poachers from hunting it. Crocodile skin is highly prized for its commercial value in the fashion industry, and the meat and eggs are considered delicacies.

As its name implies, the saltwater crocodile is found mainly in the salt marshes and wetlands of India’s east coast down through Australia. Males can grow up to 20 feet in length and weigh up to 2,300 lbs. In general, they’re about four to five times bigger than female saltwater crocs and are surprisingly agile.

Tsetse Fly

The tsetse fly is similar to the mosquito in that its lethality comes not from the fly itself, but from the highly infectious diseases it spreads – mainly sleeping sickness that affects both humans and animals. It’s found predominantly in tropical Africa and is generally divided into three different categories: savannah, forest and riverine.

Areas infested with tsetse flies are also doubly affected because they make raising cattle and other livestock virtually impossible, resulting in hunger, famine and general poverty. Surprisingly, the easiest and most inexpensive way to control the tsetse fly population is with a simple blue tarp; the color confuses the flies and allows them to be collected and killed. 

Western Taipan Snake

Unless you’re trekking through the outback of eastern Australia, it’s highly unlikely you’ll ever come across this snake that’s considered to be one of the deadliest in the world. It’s not even particularly aggressive for a snake, but if it does strike you, better have your affairs in order. Its venom is the most toxic of any snake on the planet.

The deadly venom is a mixture of neurotoxins, hemotoxins and various other elements that affect numerous parts of the body. Also known as the inland snake, the western taipan is protected by special conservation laws and can be safely observed at several zoos in Australia, Russia and the U.S.

Hippopotamus

The name “hippopotamus” is derived from Greek meaning “river horse,” which is not at all what comes to mind when looking at the stout, stocky and altogether awkward hippo – the third-largest land mammal in the world. And though they’re generally herbivores and not territorial, their aggressive and unpredictable behavior can be extremely dangerous.

A fully grown male hippo can weigh up to 3,300 lbs. Even on land, the hippo can be surprisingly fast – they can reach top speeds of 19 mph over a short distance. And it’s not unheard of for male hippos to attack boats and other small crafts in the rivers and streams of sub-Saharan Africa. They’re very territorial, and kill thousands of people every year.

Bull Shark

Despite their small size in comparison to bigger sharks like great whites, the bull shark is among the deadliest known to man. They’re incredibly aggressive, quick to attack and hunt and swim mainly in shallow, coastal waters, which means they’re much more likely to encounter humans – which doesn’t always end well.

Unlike many other species, female bull sharks are generally bigger than the males, and can top out around eight feet in length and weigh 300 lbs. Though they prefer to hunt in the murky shallows of warm coastal waters, they can identify bright colors and other nearby objects. Even worse? They’re opportunistic feeders and will feed whenever they can.

Deathstalker Scorpion

Even if you’re the kind of person who doesn’t usually get freaked out by scorpions, this one is definitely worth panicking over. Also known as the yellow or Naqab desert scorpion, the Deathstalker is one of the most dangerous scorpions in the world thanks to its highly toxic venom and painful sting.

The Deathstalkers preferred habitat is desert and arid shrubland areas that span from the Sahara and Arabian desert through Egypt and Ethiopia. If you do happen to get stung, there has been a breakthrough development in anti-venom treatments, but (of course) the Deathstalkers venom has been proven to be very resistant.

Great White Shark

It’s almost impossible to think of the great white shark without thinking of Steven Spielberg’s “Jaws,” which was based on a novel about a shark that terrorizes a small beach community on the Fourth of July. Great white sharks love to hang out in warm, coastal, offshore waters of places like Mexico, South Africa and the United States – all places that ensure contact with humans.

The great white has no natural predators (who’d want to mess with a shark that can weigh up to 4,000 pounds?) and hunts everything from fur seals and seabirds to sea lions and other marine animals. In fact, humans aren’t a natural prey for great white, but close contact with great whites can provoke attacks, which number in the hundreds every year. 

African Bee

There’s a slight misconception in just why the African bee, which is in many ways similar to the average European bee, is so dangerous. Scientists have discovered their sting is not much more venomous than the typical bee sting, rather, it’s aggressiveness with which the bees attack.

African bee colonies are extremely aggressive and prone to swarming. If they perceive a threat to the hive, they’ll send out three to four times as many bees as a European bee colony would. Think of it as quantity over quality. The more bees there are, the more opportunity there is for them to sting, and the more likely it is that the unfortunate victim will suffer maximum damage. 

Bullet Ant

Venomous stinging ants seem like something made up by the writers of a Sci-fi movie, but these nasty little guys are all too real. They were discovered in 1775 by a Danish zoologist, and got the nickname “bullet ant” because some victims have likened the pain of their attack to a gunshot wound.

The only good thing about these ants, which live in the tropical rainforests on the eastern side of South America, is that they’re not naturally aggressive or territorial. They are foragers, not hunters, and they generally only attack when defending their nests, which can contain up to several hundred worker ants, as well as a queen. 

Stonefish

Similar to the pufferfish, the stonefish is a highly toxic marine fish that has nevertheless become a sought-after delicacy throughout Asia and the Indo-Pacific. It delivers its venom through a ridge of fins on its back, which can be easily stepped on or disturbed by swimmers. The worst part? The more pressure that is applied, more venom is released.

Stonefish stings can be incredibly painful and sometimes lethal. As recently as 2008, more than a dozen non-fatal stings were reported in Queensland, Australia. But in one of nature’s ironic twists, stonefish meat is actually quite sweet and mild, and can be eaten safely if the venom-packed fin spikes are removed. 

Deer

This one may not seem so obvious, but in reality, deer are one of the most dangerous animals in America. The problem? Humans are encroaching on their natural habitat, and forcing deer populations into close quarters with more roads and highways, leading to an increase in deer-related car crashes.

That’s why those “deer crossing” signs you see on the side of the road should be taken extremely seriously. (It’s also where the phrase ‘deer in the headlights’ originated). It’s estimated deer-related car accidents kill more than 100 people every year, which is more than dogs, horses, spiders and snakes combined. 

African Elephant

The African bush elephant is the largest terrestrial mammal on the planet, and one of the deadliest, too. Their overwhelming size is one factor – fully grown males can stand up to 13 feet tall and weigh over 6.5 tons, while females are generally about half as big. Their tusks alone can reach up to eight feet in length.

Elephants are highly intelligent creatures and can be quick to attack when provoked or threatened by poachers and hunters. In some cases, elephants have been known to go on rampages that kill hundreds of people. And like deer, their natural habitat is shrinking, which makes more such confrontations inevitable. 

Spotted Hyena

Humans and hyenas go way back. There are depictions of hyenas in the cave paintings at Chauvet, which date back nearly 40,000 years. They’re famous for being vulture-like scavengers that will eat literally anything, but the spotted hyena is also an aggressive predator that can (and will) attack humans.

Hyenas are built for power and speed. Males can grow up to five feet in length and weigh more than 100 pounds, with powerful jaws and a bite capable of crushing bones in a matter of seconds. They typically roam in packs, and have been known to attack more frequently at night.

Komodo Dragon

Found exclusively in a handful of Indonesian islands, the Komodo dragon is the largest species of lizard in the world and a deadly predator. They sit at the very top of the food chain, and hunt pretty much anything that walks (and sometimes not – they’ve also been known to scavenge carrion).

Their enormous size (males can grow up to 10 feet long and weigh over 200 pounds) makes it easy for them to kill their prey outright. This happens through a combination of the dragon’s razor-sharp slashes and venomous bite that prevents the victim’s blood from coagulating. In recent years, they’ve been put under special conservation status in Indonesia, and even have their own national park. 

Boomslang Snake

The boomslang is found only in sub-Saharan Africa and is generally considered to pose a threat to only the small animals it feeds on. You have to give this highly venomous tree snake a little credit; it’s a fairly timid species and won’t attack anything too big for it to eat or strike unless it’s provoked.

But what makes this snake so lethal is its highly toxic venom, which is designed to stop the victim’s blood from clotting, leading to massive internal and external bleeding. Also, it can open its jaws a terrifying 170 degrees, and has larger-than-usual fangs to ensure a secure bite. The worst part? It can take hours for symptoms to develop.

Australian Funnel-Web Spider

What’s scarier than a highly toxic spider? A highly toxic spider whose fangs are powerful enough to penetrate through fingernails, shoes and other soft materials. Thankfully, the Australian funnel-web spider is only found on the eastern coast of the island continent, making it highly unlikely you’ll ever encounter one.

But if you did, even the smallest bite should be considered extremely dangerous. The funnel-web spider’s venom is one of the most lethal in the world and works extremely quickly, producing symptoms ranging from nausea and confusion to shortness of breath and muscle spasms. And pray that it was a female that bit you; they’re generally considered to be less toxic than males.

Blue-Ringed Octopus

Octopuses are some of the ocean’s strangest creatures, and in the case of the blue-ringed octopus, one of the deadliest. Their venom is extremely lethal, containing high doses of compounds that induce nausea, respiratory failure and heart failure. As of now, there is no known anti-venom.

The blue-ringed octopus is small, usually only about five to eight inches in diameter, and hunts shrimp, crab and other small prey. It spends most of its time hiding from larger predators, but is quick to attack if provoked, displaying its signature blue-ringed pattern in a highly visible threat display.

Portuguese Man O’War

Just the mere sight of a single one of these venomous hydrozoa (yes, they’re actually not jellyfish) on a beach can be enough to warrant closing it to the public. Their tentacles, which can extend for as long as 30 feet below the surface, sting and paralyze their prey, but don’t worry – for humans, it’s more painful than it is deadly.

They typically can be found in groups of up to 1,000 or more (which is pretty scary, if you think about it), and attract other animals who feed on the smaller fish that seek shelter among their stinging tendrils. At least they’re easy to spot, thanks to the blue-purple tinged bladder that sits on the ocean’s surface.

Assassin Bug

The assassin bug lives up to its name with a terrifying method of killing its prey. It uses its long proboscis to inject a venomous saliva that liquifies the insides of its prey, making it easier to digest. But what makes the assassin bug truly dangerous to humans is the fact that there are some species that feed on blood, making them as deadly as mosquitos.

One species in particular, the “kissing bug,” gets its name from how it bites the soft tissue of the eyes and lips of sleeping humans. Found primarily in Central and South America, these bugs have been known to spread a tropical parasitic illness, Chagas disease, that kills around 12,000 people every year.

Rhinoceros

These giant herbivores are some of the largest creatures on Earth and are hunted for the very thing that makes them so dangerous – their horns. They’re highly coveted by trophy hunters and poachers, and are even believed to have medicinal properties in some cultures. Every year, people are gored by black rhinos, who are the most aggressive of all.

Black rhinos can weigh up to 6,000 lbs. and are shockingly agile; in short distances over open ground they can reach speeds up to 34 mph. And though poaching and hunting has made them wary of humans, it’s still best to keep a safe distance, lest they perceive a threat. 

Leopard

With a top speed of 36 mph and incredible agility and strength, the leopard is a fearsome predator in sub-Saharan Africa and Southeast Asia. They typically stick to hunting wild prey at night, but have been known to attack sick or injured humans if they are desperate enough, or if their territory is invaded.

In fact, there are two well-known cases of so-called “man-eating leopards,” both of which occurred in India. The first, the Leopard of Rudraprayag, was reported to have killed more than 100 villagers between 1918 and 1926. Panar Leopard, the second, was far more deadly, killing 400 people in the early 19th century.

Giant Pacific Octopus

Though not nearly as dangerous as the blue-ringed octopus, the giant pacific octopus is one of the ocean’s deadliest predators, eating literally anything it can get its tentacles on; shrimp, lobster, snails – even other octopuses. There have also been reports of Giant Pacific octopus attacking small sharks, making this one crafty cephalopod.

All octopuses contain toxins that paralyze and digest their prey, and the Giant Pacific is no different. It uses its tentacles and compressible body to smother fish and other small marine animals before injecting the toxin, which goes to work immediately. And just how big do they get? Guinness World Records lists the biggest one at weighing more than 600 lbs. with a reach of around 30 feet.

Six-Eyed Sand Spider

A cousin to the highly venomous recluse spider, the six-eyed sand spider is just as dangerous, though not quite as common. These medium-sized spiders are found mainly in sandy areas in southern Africa. They get their name from their preferred method of attack – they hide their flattened bodies in the smooth sand and strike when small prey (or a foot) is near.

The six-eyed sand spider contains a highly dangerous venom with necrotic effects that can lead to severe tissue damage, infection and even death. What makes this spider even more scary is that it can go up to a year without eating, making it one of the most patient killers around.