What is most dangerous animal

Interested in discovering the most dangerous animals in the world? Read on for the 15 deadliest animals on earth!

With so much biodiversity our world is full of animals that come in all shapes and sizes. And animals that are dangerous to humans are no different – they range from tiny worms to the largest land animals.

In this article, we’ve tried to rank the most dangerous animals using the criteria of the estimated number of human deaths they cause each year. We’ve excluded human beings from the list – if we’d included them they would probably rank as the second most dangerous animal, responsible for an estimated 490,000 intentional murders per year.

Because of the way we’ve compiled the list (estimated human deaths caused by animals) there are many dangerous animals not on this list that could easily prove fatal to a human, if not treated with the respect that they deserve. We’ve added a section on honorable mentions of these animals – extremely dangerous, but not big killers – at the bottom of the page.

So, with this context in mind, here’s our list of the most dangerous animals in the world:

Box jellyfish

Responsible for an estimated 100 deaths per year

A box jellyfish in the deep sea

Box jellyfish are found floating at slow speeds (up to 8 kilometers per hour) in warm coastal waters all around the world, but the deadly variety tend to live in the Indian and Pacific Oceans around northern Australia.

Considered the most venomous marine animal in the world, their bioluminescent box-like shape drags around 15 tentacles growing up to 3 meters each, all lined with thousands of nematocysts, or stinging cells. Their toxins attack the skins, nervous system, and heart, and whilst antivenom does exist for the box jellyfish, most casualties go into shock and die of drowning or heart failure well before they get to a hospital.

Cape Buffalo

Responsible for an estimated 200 deaths per year

Cape Buffalo – one of the most dangerous animals in Africa

The Cape buffalo is without a doubt one of the most dangerous animals in Africa, and is sometimes referred to as ‘widowmaker’ or ‘the black death’.

These aggressive and unpredictable beasts can weigh up to 1,000 kgs and grow up to 1.7 meters tall. They’re fearless and will mob any predator that dares to take its young. They usually travel in herds but are one of the few animals in Africa that will actively stalk and kill humans if alone.

The buffalo was a favourite of trophy hunters (hence their status as one of the big five), and are known to attack humans by circle back on their victims before charging, then trampling or goring them to death using their sharp horns. Buffalos kill an estimated 200 people every year.

Lion

Responsible for an estimated 200 deaths per year

One of Africa’s most iconic predators

As the apex predator of the African wild, the lion is one of the world’s top predators. Whilst humans are not their natural prey, each year an estimated 200 people are killed by lions. Sick male lions are mostly responsible for this death rate, along with opportunistic attacks in areas where the lions’ natural prey has been depleted.

Whilst there have been a handful of reported deaths of tourists or guides being killed by this keystone species during a safari game drive, these cases are very much the exception. The vast majority of humans killed by lions are of locals going about their daily lives in or on the fringes of African game reserves.

African Elephant

Responsible for an estimated 500 deaths per year

The largest land animal, and one of the most dangerous

Reaching weights of up to 7,000 kg the world’s largest land animals can often be unpredictable, with older bull elephants, young males, and elephants with babies particularly dangerous to anything that crosses their path. Unprovoked attacks by elephants on humans are occasionally reported, usually by male elephants in musth (a sexually active period when testosterone levels increase).

Each year around 500 human deaths are caused by African elephants trampling and crushing their victims. In areas where poaching occurs, or the elephants’ habitat is in danger, elephants tend to be much more aggressive.

Tapeworm

Responsible for an estimated 700 deaths per year

A tapeworm closeup

There are a large number of tapeworm species – parasites that live in the small intestines of many different species of animals. The Echinococcus group of tapeworm are most dangerous to humans, and measure just 6 millimeters in length, and found in raw or undercooked meat. Their size is not indicative of the damage they can cause, however, which if left untreated leads to severe symptoms and can be fatal.

Nile & Saltwater Crocodile

Responsible for an estimated 1,000 deaths per year

Killer saltwater crocodile

Found in the tropical regions of Africa, Asia, Australia, and the Americas, crocodile live in lakes, rivers, wetlands, and even some saltwater areas. The larger saltwater crocodile and Nile crocodile species are the most dangerous, regularly killing people in parts of Asia and Africa. (Know the key differences between crocodiles and alligators?)

Known for their ambush hunting technique, the crocodiles are indiscriminate hunters and attack any animal that comes within reach – including humans. Their attack usually takes the form of launching from the water and clamping its victim in its powerful jaws, dragging them back into the water to drown them before stashing them under submerged branches or rocks to eat later.

Attacks on humans usually occur when people are washing close to riverbanks and lakeshores, and when fishermen are getting in and out of their boats. Around 40% of crocodile attacks on humans are fatal, with children more at risk than adults due to their size. The risk of crocodile attacks has been shown to increase in the warmer season when the crocodiles have more energy.

Hippopotamus

Responsible for an estimated 3,000 deaths per year

The hippo is Africa’s most dangerous animal

With so many dangerous animals in Africa, many people often overlook the fact that the hippopotamus is actually the biggest killer of humans of all large African animals. Although hippos are herbivores, these highly territorial animals are estimated to kill an incredible 3,000 people per year.

Male hippos fiercely defend their territories – which include the banks of rivers and lakes, while females hippos can get extremely aggressive if they sense anything getting in between them and their babies, who stay in the water while they feed on the shore. (Did you hear about the pink hippo milk rumour?)

Hippos weigh up to 1,500 kg – the third biggest animal in Africa behind the elephant and rhino – and can run on land at speeds of up to 30 km per hour. Combine this with their aggressive nature, agility in and out of the water, and sharp, half-meter teeth in enormous jaws, and you can understand why hippos make for such a fearsome creature to encounter.

Ascaris roundworms

Responsible for an estimated 4,500 deaths per year

Ascaris roundworm

The Ascaris roundworm parasites are most commonly found in cats, dogs, and foxes, and can infect humans if they handle soil or sand contaminated with infected animal faeces. For most people, an infection causes no symptoms and the parasites die within a few months, but in some cases the roundworm larvae infect organs such as the brain, eyes, or lungs, and cause severe symptoms and eventually death.

Tsetse Fly

Responsible for an estimated 10,000 deaths per year

A tsetse fly lands on a human

Tsetse flies may look similar to a housefly, but is undoubtedly far more dangerous.

Endemic to sub-Saharan Africa the flies are blood-suckers that carry -and spread – deadly parasites known as trypanosomes. These tiny pathogens are responsible for African sleeping sickness, which can lead to death if left untreated.

There are no vaccines for this disease borne by tsetse flies, though prevention of tsetse bites is helped by wearing neutral-colored clothing (ideally permethrin-treated) and avoiding bushes during the daytime.

Freshwater snails

Responsible for an estimated 20,000 deaths per year

A freshwater snail on seabed

The freshwater snail is another animal that’s extremely dangerous due to the parasites it carries. In this case, the parasitic flatworms found in freshwater snails can infect humans with schistosomiasis (also known as fever or bilharzia), a disease that causes intense abdominal pain.

Schistosomiasis is second only to malaria as the parasitic disease with the highest death rate, causing over 20,000 deaths a year. Transmission to humans comes from the parasites emerging from the snail to contaminate water, which then infects any humans who touch or drink it.

Dogs

Responsible for an estimated 35,00 deaths per year

A rabid dog – one of the biggest human killing animals on earth

Man’s best friend is also one of our biggest killers. Around 35,000 humans die each year of rabies (mostly in Africa and Asia), and it’s estimated that approximately 99% of those cases are caused by the saliva of infected dogs.

Snakes

Responsible for an estimated 100,000 deaths per year

Black mama – Africa’s most dangerous snake

It would have been hard to list each snake species of dangerous snake separately along with their kill numbers, as for most snakebite deaths the species of snake is not known by the person who was bitten. That said, there are plenty of species of exceptionally venomous snakes living in many parts of the world.

Black mambas are generally regarded as one of the most deadly snakes in the world, and for good reason. They are large, one of the world’s fastest snakes, have a well-developed vision, and are a highly aggressive snake when cornered – known to attack and strike repeatedly. On top of this behaviour, black mambas have extremely toxic venom, with one bite containing enough neuro and cardio-toxins to kill 10 people, and a 100% fatality rate for untreated bites.

Mosquito

Responsible for an estimated 1,000,000 deaths per year

Mosquito – the most dangerous animal in the world

Although the tiny mosquito may look far less impressive than the other large creatures on this list, it is far and away the most dangerous animal in the world. The many species of mosquito – in sub-Saharan Africa and Asia particularly – carry a number of different potentially fatal mosquito borne diseases, including Yellow Fever, Zika virus, West Nile virus, Dengue Fever, and of course Malaria. Between them, these diseases kill an estimated one million people each year. The World Health Organization says that:

“Of all disease-transmitting insects, the mosquito is the greatest menace, spreading malaria, dengue and yellow fever, which together are responsible for several million deaths and hundreds of millions of cases every year” (full source)

Active from dusk to dawn, prevention against mosquito bites takes the form of wearing light colours, using spray or lotion repellents, and sleeping in mosquito nets.