Skip to Content

What Snake Ranks as the Most Dangerous in the Americas?

I watch a lot of survival shows on TV, and often the protagonists are most worried about encountering deadly snakes. I have often wondered exactly which snake is the most dangerous, so I did some research. I decided to share my findings in this article.

The most dangerous snake in the Americas is the Fer-de-Lance, known locally as Terciopelo. It is an aggressive species of pit viper found in Central and South America. A bite can have enough potency to kill up to 32 people. Its venom produces a hemotoxin, which destroys the tissue around the bite.

The rest of this article will give you details on the Terciopelo as well as the most dangerous snakes if every region of the Americas. That way, you will know what to look out for in the area you live or are visiting.

Green Fer-de-Lance Snake on a Log

The Most Dangerous Snake in the Americas

The most dangerous snake is often difficult to pinpoint because it depends on the definition of ‘dangerous.’ Snakes with the most deadly venom are not necessarily the most aggressive, for example.

To truly obtain the most dangerous snake, the following categories must be factored in:

  • The average size of an adult snake
  • Average venom released in a bite
  • Toxicity of the venom
  • The level of aggression
  • The number of deaths per year from each species.

When all of that is considered, the Fer-de-Lance (Bothrops asper) is the most dangerous snake in the Americas.


The Fer-de-Lance (Bothrops asper), more commonly known as the Terciopelo or Barba Amarilla, is a pit viper with both light and dark brown markings that enable it to blend into its surroundings. It can grow to six feet in length, with a head size of up to four inches wide and fangs that can be almost an inch long.

The venom produced by the Terciopelo is a hemotoxin. Hemotoxins attack the blood and cause clots that can destroy the tissue around it. When threatened, this snake will raise itself up before attacking, so it often bites and injects this venom above the knee. The Fer-de-Lance is dangerous, in part, because it is very aggressive.

Mortality Rate

The Terciopelo is responsible for nearly half of the snakebites in Costa Rica, which is one of its favorite places to reside. Fortunately, the number of deaths caused by this viper, and most others in the Americas, is only about 9%. It’s the sheer number of attacks that make this snake so deadly. In fact, half of all venomous snake bites are perpetrated by the Fer-de-Lance.

The Clodomiro Picado Research Institute produces snake antiophidic sera, which prevents most bites from becoming fatal. The severity of the bite and the location on the body largely determine survivability.

Geographic Range

Moist environments are generally the home of choice for the Terciopelo. They can often be found in Colombia and Ecuador’s forests, the cloud forests of Guatemala and Mexico, and Costa Rica. However, these dangerous snakes don’t limit themselves and have been known to live in drier areas near water.

What Are the Most Dangerous Snakes in North America?

There are quite a few venomous snakes in North America. Here are the 3 most deadly:

  • Eastern and Western Diamondback Rattlesnakes – These snakes can grow to a length of nearly eight feet and have a distinct diamond pattern on their backs, hence the name. Both the Eastern and Western are quite aggressive if you invade their space and sport large fangs and rattles. Their smaller cousin, the Timber Rattlesnake, is also quite dangerous.
  • Mojave Rattlesnake – These snakes may not look as intimidating as the others since they are only three or four feet long. Still, they pack a potent venom that causes blurred vision and respiratory failure. Mojave Rattlesnakes have a light brown body with large, dark brown circles running down it’s back.
  • Cottonmouth (also known as Water Moccasin) – This snake is the only semi-aquatic viper known to man. The Cottonmouth is also incredibly aggressive, with a cytotoxic venom that eats away flesh, and it prefers to hide in water and attack unsuspecting victims. They get their name from the white coloration inside their mouth, which contrasts with their dark olive or black scale coloring.

What Us State Has the Highest Number of Snake Bites?

North Carolina, where I happen to reside, is reported to have the highest number of reported snake bites, out of all the U.S. states. The majority of the bites have occurred around the Raleigh area, suggesting that the continued population growth is encroaching on snake habitats and people don’t generally know what to do if they encounter a snake.

Scientists also report that there is an increase of bites after heavy rainfall. Other states with high bite numbers include Georgia, Texas, and Florida (where I was raised).

Which American Snake Bite Kills Fastest?

Because of advances in medicine and anti-venom, fatalities from snake bites in the U.S. are quite rare. The Eastern Coral Snake has enough venom to kill five people, and a hefty dose of the venom can kill a human within two hours. Fortunately, it is a reclusive snake that mainly bites for defense, and usually injects only a small amount of venom. I grew up in Florida and always heard stories about the dangers of being on the water and falling into a coral snake nest.

Do Any States Not Have Poisonous Snakes?

Alaska and Rhode Island are the only states in the United States that have no native venomous snakes. Several states only have one species, however: Delaware, Hawaii, Maine, Minnesota, Michigan, Montana, New Hampshire, North Dakota, South Dakota, Vermont, and Washington.

To find out about the venomous snakes found in your state, check out this web page.

What Are the Most Dangerous Snakes in Central America?

  • Fer-de-Lance (Bothrops asper) – The large, aggressive snake is the most dangerous in the Americas.
  • Common Lancehead – This snake is also known as a Fer-de-Lance (Bothrops atrox). The Common Lancehead is shorter, stretching to only five feet, with darker brown markings than the Terciopelo. This viper, however, is more defensive than aggressive. It is commonly found on banana and coffee plantations, where it hunts for small animals.
  • Bushmaster – This viper can reach nearly ten feet in length and are the longest venomous snake in the western hemisphere. While its venom is not as potent as other vipers in Central America, it administers a large amount of venom when it bites, and it can strike several times in succession, making it quite deadly. The Bushmaster is a nocturnal snake that has triangular patches of black scales that run the length of its body.

What Are the Most Dangerous Snakes in South America?

  • South American Rattlesnake – This snake is particularly dangerous because it is the most venomous of all the rattlesnakes. If not treated, the likelihood of a bite being fatal is 75%. The venom can also cause permanent vision problems or blindness. The South American Rattlesnake can be found in many countries in both South and Central America.
  • Golden Lancehead – This viper mostly eats birds, and its venom is so quick that its prey can’t fly away. The Golden Lancehead’s venom is noticeably more potent than other Lanceheads. Fortunately, this snake is only found on an island off of the Brazilian coast.
  • All three of the most dangerous snakes in Central America can be found in South America, too.

Final Thoughts

I was actually surprised to find out that the Copperhead did not make the list of most dangerous snakes. I guess that’s because they are mostly on my radar since I live in the Southeastern United States. At least that is good news for me that they aren’t nearly as deadly as those near the top of the list!

If you have ever encountered a deadly snake, please share your story in the comments. Thanks for stopping by.

For more, check out What to Do if You Encounter a Snake While Hiking.