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The Top 10 Most Dangerous Wild Animals in the U.S.A.

Since completing university in England, Paul has worked as a bookseller, librarian and freelance writer. He currently lives in Florida.

The U.S. is home to many wild predators, but which are the most dangerous?

The U.S. is home to many wild predators, but which are the most dangerous?

In most situations, humans pose far more danger to wild animals than they do to us. In the United States, wild animals are injured or killed frequently via hunting, vehicular traffic, destruction of natural habitats, accidental poisoning of food or water supplies, and other human activity.

That said, humans are also occasionally injured or killed by wildlife. Below—in no particular order—is a list of what I consider to be the most dangerous wild animals in the United States in terms of potential for injury or death. For the purposes of this list, only animals that can attack humans directly (via bite, sting, scratch, etc.) are included. Animals that can spread disease or are poisonous if consumed are not considered.

Before we dive into the list, however, I should make it clear that practically all wild animals tend to avoid human contact and don’t present much of a threat unless they are provoked, shocked, surprised, or protecting their young from harm. If approached by a human, most wildlife will attempt to hide or escape if possible.

The 10 Deadliest Wild Animals in America

Listed below (in no particular) order are 10 U.S. animals that are capable of causing harm or death in humans.

  1. Alligator
  2. Cougars
  3. Coyotes and Wolves
  4. Spiders
  5. Scorpions
  6. Bees and Fire Ants
  7. Bears
  8. Wild Boars
  9. Snakes
  10. Sharks, Stingrays, and Portuguese Man O’ War
American alligators are found in the southeastern areas of the U.S. Although timid by nature, they can pack a powerful bite if surprised, confused, or threatened.

American alligators are found in the southeastern areas of the U.S. Although timid by nature, they can pack a powerful bite if surprised, confused, or threatened.

1. Alligators

Alligators are found primarily in the southeastern United States. They are normally pretty timid and in most cases will attempt to escape if approached. However, their skill at remaining motionless for extended periods and their ability to camouflage themselves can make it possible to stumble across them accidentally.

They are quick moving over short distances and have an incredibly powerful bite perfect for cracking open turtle shells. Like most animals, they can also be aggressive if they feel that their young are threatened. You should always remain a safe distance from these large reptiles and never provoke them.

  • Size: 440–770 lbs
  • Range: Southeastern U.S.
  • Average Deaths Per Year: < 1

2. Cougars

Also known as pumas, mountain lions, panthers, and catamounts, these big cats can be ferocious fighters and live across the western United States. However, they do not see humans as prey, so attacks are extremely uncommon. Across the whole of North America, there have only been 88 recorded attacks and 20 fatalities since 1890.

Cougars that are starving for food are the most likely to attack. Juveniles who are searching out new territory can also be aggressive. These cats typically attempt to subdue their prey with a bite to the neck.

In the event of an encounter with an aggressive cougar, it is important to be loud and assertive. Look at the animal but avoid direct eye contact so as not to appear aggressive. Do make loud noises and try to appear as large as possible by opening your jacket. Throw sticks and stones in its direction (but not directly at it) to scare it off. Do not behave passively or try to play dead.

  • Size: 64–220 lbs
  • Range: All of U.S. (but much more common in western and central states)
  • Average Deaths Per Year: < 1
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Wolves are far less common than they used to be, and attacks on humans are extremely rare.

Wolves are far less common than they used to be, and attacks on humans are extremely rare.

3. Coyotes and Wolves

Coyote attacks on humans are extremely rare. These wild dogs are dangerous, however, and a pack of coyotes is certainly capable of killing an adult.

Coyotes are also able to mate with domestic dogs, producing “coydogs,” which are canines that have the predatory instincts of a coyote but may have less fear of humans, which can be a dangerous combination.

More of a threat to livestock than humans, coyotes and coydogs should be treated with respect and distance.

Wolves can behave aggressively towards people, but U.S. attack numbers are low, although they have increased in recent years. It is important to note that wolves are naturally afraid of humans, so attacks don’t happen very often.


  • Size: 15–44 lbs
  • Range: All of U.S.
  • Average Deaths Per Year: < 1


  • Size: 82–88 lbs (average)
  • Range: Forrested and mountainous areas in northern U.S.
  • Average Deaths Per Year: < 1

4. Spiders

The two most venomous spiders in the U.S. are recluse spiders and widows. Despite its small size, the brown recluse is the most dangerous type of spider, with a bite that can develop into a necrotic ulcer capable of leading to gangrene and permanent tissue damage if untreated. This spider is also sometimes referred to as a “fiddle-back” because of the violin-shaped mark on its abdomen.

There are numerous species of widow spiders that live in the U.S. The black widow is the most notorious, given its recognizable markings and the dangerous bite of the female (as well as her habit of eating the male after mating with him). Thanks to anti-venom, the bite is not often fatal if medical treatment is sought out quickly.


  • Size: .5–1.5 inches (with legs)
  • Range: Southern central U.S.
  • Average Deaths Per Year: < 1


  • Size: .5–2 inches (with legs)
  • Range: Most of U.S. (native to and more concentrated in southern states)
  • Average Deaths Per Year: < 1
There are around 90 different species in the country, the most dangerous of which is the bark scorpion, which is most commonly found in the Arizona area.

There are around 90 different species in the country, the most dangerous of which is the bark scorpion, which is most commonly found in the Arizona area.

5. Scorpions

There are around 90 different species of scorpion in the U.S., with the highest concentration in the southwestern area of the country where the climate is hot and dry. Most scorpion stings are not considered life-threatening to humans, although they can be extremely painful. The most venomous species in the country is the bark scorpion, which can be found in Arizona and some other southwestern states.

  • Size: 0.5–10 inches
  • Range: All of U.S.
  • Average Deaths Per Year: < 1
Red imported fire ants are among the most aggressive ant species in the U.S. and will not hesitate to bite if there is a threat to the colony.

Red imported fire ants are among the most aggressive ant species in the U.S. and will not hesitate to bite if there is a threat to the colony.

6. Bees and Fire Ants

Africanized honey bees, sometimes called “killer bees,” are an aggressive type of bee that has resulted from the cross-breeding of African honey bees with other varieties. They are spreading up through the southern United States from the Mexican border.

Although there is widespread fear of killer bees, their sting is no more potent than that of a normal honey bee, and only one or two people die each year from stings. They are easier to provoke, faster to swarm, and attack in larger numbers than other types of bee, however, so they should always be respected when encountered.

Another insect to avoid is the fire ant, especially the red imported fire ant, which is considered by many to be the most aggressive species in the U.S. These insects can bite and sting if they think that their colony or food source is under attack. Their sting is intense, causing a painful burning sensation. A white pustule often appears a couple of days later. Very occasionally, there can be an allergic reaction. If this happens, hospital treatment should be sought.


  • Size: < 1 inch
  • Range: All of U.S. (Africanized honey bees only in south-central and southwestern U.S.)
  • Average Deaths Per Year: 43–89 (includes hornets, wasps, and bees)

Fire Ants

  • Size: 1/8–1/4 inch
  • Range: South-central and southeastern U.S.
  • Average Deaths Per Year: Unknown (but likely < 1)
Once common, grizzly bears have dwindled in numbers.  Black bears are the most commonly encountered. They are less aggressive than grizzlies but can be fierce if provoked.

Once common, grizzly bears have dwindled in numbers. Black bears are the most commonly encountered. They are less aggressive than grizzlies but can be fierce if provoked.

7. Bears

Bears have a ferocious reputation, but like other wild animals, they are unlikely to attack unless provoked, protecting their young, or starving. Usually, they will run away or stage mock charges. If you are unlucky enough to be attacked by a bear, you should fight back—not submit or play dead.

There are two main species to be found in the U.S.: brown bears (grizzlies) and black bears. Brown bears were once common, but population numbers have declined, and they are now only found in Alaska, Idaho, Montana, Washington, and Wyoming. Grizzlies are larger and more aggressive than black bears. They are especially dangerous because they have an exceptionally strong bite that is said to be powerful enough to crush a bowling ball.

Black bears are far more widespread and common than brown bears. Although they generally prefer to stay in forested areas, they can come into populated areas in search of food. Despite their name, black bears vary in color and aren’t necessarily black.

  • Size: 90–500 lbs
  • Range: Many parts of U.S.
  • Average Deaths Per Year: 1–2

8. Wild Boar

Wild Boar (also called pigs and hogs) arrived in the U.S. with Spanish explorers as farm animals. Some of them escaped into the wild and developed into a feral population.

These wild pigs should be treated with respect, as they are capable of being very aggressive, especially during mating season or if they believe their young are under threat. Boars will charge an intruder, usually to warn them off, but if contact is made, their tusks can cause serious wounds.

  • Size: 99–220 lbs
  • Range: Southern U.S., California, and small, scattered areas throughout the western U.S.
  • Average Deaths Per Year: < 1
Two male northern pacific rattlenakes perform a "combat dance."

Two male northern pacific rattlenakes perform a "combat dance."

9. Snakes

Despite fatalities from snakebites being extremely rare in the U.S., these reptiles still inspire fear. There are basically two categories of venomous snakes that can cause serious harm. These are pit vipers and coral snakes. Pit vipers include rattlesnakes, copperheads, and cottonmouth snakes.

There are 25 species of rattlesnake in the U.S. and Mexico, possessing bites that can be anywhere from mild to seriously venomous. Some rattlesnakes have bites that are capable of killing a human.

One type of rattlesnake to watch out for is the eastern diamondback, which lives in North and South Carolina, Louisiana, and Florida and can reach 84 inches (2.4 meters) in length, making it the largest venomous snake in the U.S.

Another type to be aware of is the western diamondback, which inhabits an area from Arkansas to southern California, Oklahoma, Texas, New Mexico, and Arizona and is also very aggressive, delivering a haemotoxic venom. The Mojave rattlesnake lives in desert areas in the southeast. It is relatively short but delivers a powerful bite.

Copperheads are another type of venomous pit viper that should be avoided. As their name suggests, they are copper in color. They rely on camouflage to keep themselves hidden from their prey, but this makes them easy to tread on by accident. Their bites are usually mild but can be very serious in some circumstances.

Cottonmouths or water moccasins are aggressive, semi-aquatic snakes that live in the southeastern United States and are capable of delivering a painful bite. They often hang around near water where they hunt for prey. The inside of the snake’s mouth is white, hence the name “cottonmouth."

Coral snakes are related to cobras, and there are three species in the U.S. Their bites can be dangerous, but they are shy and slow to bite, partly due to their biology. They cannot deliver a significantly venomous bite without waiting for a period of time while envenomation takes place. Statistically, most of the bite injuries caused by these snakes come from people deliberately handling them.

Coral snakes can be difficult to identify if you don’t know what you are looking for, as their markings make them easy to confuse with other types of snakes, especially king snakes.

  • Size: 2–15 lbs
  • Range: All of U.S. but depends on species
  • Average Deaths Per Year: 2–3
Shark attacks are rare but have resulted in fatalities in a number of cases.

Shark attacks are rare but have resulted in fatalities in a number of cases.

10. Sharks, Stingrays, and Portuguese Man O’ War

Out in the oceans, there are a number of dangerous creatures to be aware of. Sharks have a ferocious reputation and are certainly capable of causing great harm, but it should also be noted that the number of shark attacks across the U.S. only averages around 16 each year, with some years seeing no fatalities. The three most dangerous species of sharks, which are responsible for the most attacks on people, are great white sharks, tiger sharks, and bull sharks.

In the Gulf of Mexico, there are a number of stingray species that rest underwater on sand and rocks. They won’t attack you, but if you stand on one by accident, they can strike with their barbed tails, which inflict a poisonous sting.

Another sea creature to be aware of is the Portuguese man o’ war. It looks similar to a jellyfish but is actually a colony of minute, interconnected organisms called zooids. Its venomous tentacles are capable of delivering an extremely painful sting.

Bull, Tiger, and White Sharks

  • Size: 200–2400 lbs
  • Range: Coastal regions
  • Average Deaths Per Year: 0–2


  • Size: Varies by species
  • Range: Coastal regions
  • Average Deaths Per Year: < 1

Portuguese Man O’ War

  • Size: Tentacles can be up to 30 feet long
  • Range: Coastal regions
  • Average Deaths Per Year: < 1

So, What's the Most Dangerous Animal of All?

This may surprise some people, but my vote for the most dangerous animal in the U.S. in terms of injuries and fatalities is not actually a wild animal but a common pet.

Each year, it has been estimated that as much as two percent of the U.S. population is bitten by dogs; that works out to around 4.5 million people. Around 16–39 people are killed by dogs annually. Pitbulls and Rottweilers are responsible for the majority of deadly attacks, but smaller dogs can be dangerous too, especially when it comes to babies and young children.

So while wild animals inspire fear in many, you are far more likely to be attacked or killed by a domestic dog than a wolf, bear, coyote, or other mammalian predator. As humans, if we respect and keep our distance from wild animals when in their vicinity, we are very unlikely to come to harm.


This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.

© 2013 Paul Goodman


unnamed on August 18, 2020:

What about mosquitoes?

Yzan on March 13, 2020:

That dog above is abviosly wanting to play DUHHHH

nancy jarrett on January 01, 2020:

play dead with grizzly bears, but run, climb very high or fight back with black bears which would love to make a meal of you. the best thing is to make noise in bear territory and carry bear spray, or handgun for just in case the other things don't work. and yes dogs being habitualized and untimid of most or even being timid hurt more humans than wild animals, there are more of them living with or close to us.

Martelli Macomber on December 06, 2019:

I don't know where you got your info, but playing dead is often your ONLY chance of escaping a grizzly attack alive. That's a quick lesson you learn - along with real life examples where the tactic worked - when you move to grizzly country (in my case, northern Wyoming adjacent to Grand Teton National Park).

You can look up the details of an attack involving a couple from San Francisco visiting Yellowstone National Park a few years ago in which the bear killed the husband as he ran but let the woman be after she played dead (injured, but alive).

While young bears may mock charge, adult bears generally attack to cripple or kill and generally don't retreat until they feel they have eliminated the 'threat'.

You fight back with an adult grizzly and it's going to be a darn short one - and you aren't gong to win it!

Hayden Coombs on November 16, 2019:

Quote from a article that used facts rather than opinion- Wrong. It turns out that "other mammals," a bucket category covering everything from cows to horses to raccoons, were the most dangerous on the list, causing 1.7 deaths per 10 million people every year. (Other research has shown that most of the deaths in this category involve farm animals like cows and horses.) Hornets, wasps, and bees were slightly less deadly (1.4), and dogs came in next at 0.8.’ (Per the CDC)

Michael Hartsook on October 20, 2019:

Like you said main reason most people get bitten by a snake is by handling them or trying to catch one, I was born and raised in east Tennessee and still live here. Growing up I used to catch snakes all the time in the woods and wetlands plus there was a creek that ran through the neighborhood and i caught water snakes non venomous one,s.i caught black rat snakes corn, snakes garter snakes and caught a copperhead, or two, i had got bitten a time or two by a black rat snake and a Garter snake which was my fault every snake I caught I would turn them loose and not harm them, back in September of 2007,i was in the mountains and was trying to catch a copperhead and got bitten on the thumb when it bit,me it didn't hurt but after my hand swelled up it hurt all the way from my hand to my elbow, i spent 24 hours in the hospital and the doctor said it was a dry bite heck i would have hated to see what a real bite was like I could see the venom on my thumb where the bite marks were on my thumb. That was my fault for trying to catch it.

Realist on July 14, 2019:

The most dangerous animal in North America are humans; just ask the people in Chicago!

unnessecary name on February 01, 2019:

thanks! this really helped out for my presentation!! I can't believe the most dangerous animal as in the one that kills the most are dogs!!

gjdkfdjsf on July 27, 2015:

i cant believe that a beloved pet is the most dangerous animal in the US

Ronald E Franklin from Mechanicsburg, PA on February 07, 2014:

Well written hub with some good advice on how to protect yourself. I enjoyed reading this. Voted up.

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