The 9 Most Dangerous Animals In Puerto Rico

Dangerous Animals In Puerto Rico

Puerto Rico is a beautiful US island in the middle of the Caribbean. It’s known for its gorgeous landscapes of mountain tops, misty waterfalls, white-sand beaches, and the green El Yunque Rainforest. But these provide plenty of hiding spaces for some seriously dangerous creatures.

Although Puerto Rico isn’t known for its threatening predators, there are a few wild things that could be potentially deadly. There are centipedes, snakes, and spiders in the forests, while sharks, lionfish, and jellies await in the ocean. And, although Puerto Rico is rather a safe holiday destination by most estimations, some animals could be harmful. 

From small venomous insects crawling beneath your feet to large sea creatures and reptiles that you probably don’t want to meet, we’ve listed the nine most dangerous animals in Puerto Rico. Keep this guide handy when you travel! 

Giant centipede

Giant centipede
Photo by Envato Elements

This creepy little animal, also known by its Latin name Scolopendra gigantea, crawls around certain parts of Puerto Rico. The giant centipede is a small, colorful insect found mainly in the wooded and forested parts of the island. And, thanks to its extremely painful bite, it’s considered to be one of the most dangerous animals in Puerto Rico, too.

Although the bite of the giant centipede can be agonizing and could potentially make you very sick, it’s usually not fatal. The venom only poses a minor life threat to little children, and it’s hard to find records of any fatalities in modern times. That said, the nasty sting would probably ruin your holiday!

It’s not easy to come across this small insect while traveling around the beautiful island of Puerto Rico. Most people stick to the towns and the cities, like bustling San Juan and the surf areas of Rincon, but you probably have to venture into the forests and mountains to make their acquaintance.


spider on a web
Photo by Envato Elements

Many of us suffer from arachnophobia, a fear of spiders. There is a good reason for it – they can bite! And the bad news is that there are lots of these eight-legged arachnids around Puerto Rico, and many of them can be dangerous.

The most dangerous of all is the brown recluse. It’s a fairly small spider with long legs and a brown torso. Although they are not very common, their bites could be potentially deadly. The good news is that they fear people and rarely attack them.

Other species of spiders in Puerto Rico include:

  • The black widow – Their venom is potentially deadly to humans. They rarely bite people, only in self-defense.
  • Common Puerto Rican brown tarantula – A small, nocturnal, hairy arachnid. Their bites are harmless.
  • Banana spider – A shy spider that strays away from humans. Their bites are a little painful but not dangerous.
  • Cave spider – A harmless, nocturnal spider that lives in caves.
  • Tent cobweb weaver – Commonly found in homes. It rarely bites, and its venom isn’t harmful.


Photo by Envato Elements

Like most tropical destinations, Puerto Rico has a healthy population of scorpions. There are seven species of these tiny stingers around the Caribbean island. Although there are many deadly scorpions around the world, the ones here aren’t thought to be quite as dangerous as others in, say, South Africa or Central America.  

Although the sting of a Puerto Rican scorpion isn’t usually fatal, it is very nasty and can easily spoil a holiday. It all depends what genus of the species you encounter. Six of the seven scorpions here are tityus scorpions, which are harmful but rarely deadly. Then there’s the more dangerous bark scorpion, which has necessitated the stocking of antivenom on Puerto Rico.

Many people don’t encounter these little creatures when visiting Puerto Rico, but it’s not too hard to come by them. They can hide behind a curtain or a pillow in your hotel room, or be out in the wild. Make sure to check your sheets and clothes for scorpions if you want to avoid that painful sting.


Sharks in the sea
Photo by Envato Elements

Swimming in the ocean always brings the threat of meeting some of the scariest marine creatures in the world: Sharks. Puerto Rican waters are home to many species of sharks, but there were only two deadly shark incidents in the history of the US territory. Although fatal attacks are a rarity around the island, it’s impossible to ignore these beasts when talking about the most dangerous animals in Puerto Rico.

The good news is that most sharks in the area aren’t dangerous and don’t attack people. In fact, it’s quite rare for sharks to even get anywhere near the beaches here, so most days you can safely enjoy your swim. To stay on the safe side, though, it’s better to check for regular alerts.

The great white is considered one of the most aggressive sharks of all. It lives in the waters of all major oceans on the globe. That also includes the Caribbean around the Puerto Rican coast. Although it is unlikely that you’ll encounter the great white, it can’t be ruled out. And believe us, you wouldn’t like to be the unlucky one to come by one of those. Remember Jaws?


snake on a tree
Photo by Envato Elements

There are around ten different species of snake native to Puerto Rico. Luckily, most of them are neither venomous nor dangerous to humans. In fact, there is only one venomous snake in the region: The Puerto Rican racer.

Also known by its Latin name borikenophis portoricensis, it’s the second-largest snake in Puerto Rico. It only grows up to three feet long, is brown, and can be recognized by its neck hood, similar to that of a cobra. The racer, which mainly lives in the trees of the Toro Negro State Forest, has also been spotted in the El Yunque Rainforest. The venom of the racer isn’t deadly but can cause symptoms ranging from mild swelling to serious numbness and immobilization that could last for weeks.

Luckily, it’s unlikely that you’d get bitten by a snake in Puerto Rico, so that shouldn’t be your main concern. As a precaution, we’d recommend staying alert and wearing solid boots while hiking to avoid any nasty surprises.


Photo by Envato Elements

Another marine creature that you won’t like to encounter while enjoying the warm waters of Puerto Rico is a lionfish. This small, colorful fish is covered in spiky, venomous fin rays. The most common type in the area is the red lionfish, also known as the zebrafish. And, although it isn’t native to the Caribbean Sea, it has become an invasive species there in recent years.

The red lionfish can grow up to 18.5 inches (47 cm) long, and it can live more than ten years. Its name comes from the color of the nasty spines that grow around their bodies. Their venom isn’t usually deadly, but their stings are extremely painful. Apart from the pain, the stings can cause vomiting, headaches, and breathing difficulties.

If you see one of these nasty little fish, don’t be tempted to touch them. They use the spikes as a defense mechanism, and they’re pretty effective!


Photo by Envato Elements

Most tropical destinations are a perfect environment for mosquitos to breed, and Puerto Rico is no different. It may seem that, apart from being a little irritating, these small insects are harmless. But the fact is that Puerto Rican mozzies can give you a lot more than just an itchy bite. They can carry some serious diseases that can be potentially life-threatening.

Mosquitos are high in numbers on the island and can transmit diseases that include Zika, dengue fever, and chikungunya. All of those might need hospital treatment and can lead to death. It’s very important to protect yourself from getting bitten by using repellents or protective clothing, like DEET spray and sleeping nets.


Caiman portrait
Photo by Envato Elements

Caimans are alligatoroid reptiles that inhabit parts of beautiful Puerto Rico. They are smaller and less aggressive than their alligator cousins but can be dangerous to children and pets. Although caimans are quite large in numbers around the island, it isn’t their natural habitat. They were brought to Puerto Rico as pets and later released into the wilderness. Their population has since been growing.

Caimans found in Puerto Rico can grow up to 8 feet long and weigh no more than 88 pounds. The most common ones are speckled caimans. These reptiles like living near freshwater, especially rivers, mangroves, and lakes. They are particularly common in the Tortuguero Lagoon located between Vega Baja and Manatí.

Caimans are not known to be aggressive towards people, but there have been cases of some attacks. You should have your wits about you whenever you venture into areas near freshwater.

Box jellyfish

Box jellyfish
Photo by Envato Elements

Box jellyfish are the most dangerous jellies out there, and some inhabit the Caribbean Sea. Although those that can be found in Puerto Rican waters are not generally deadly, their stings can cause some very unpleasant symptoms. From nausea to back pains to limb cramps, these aren’t what you want to experience on your holiday.

Box jellyfish can be hard to spot because of their transparent appearance. You can get stung by touching one of their long and thin tentacles. Because of their nasty sting, they have been nicknamed sea wasps. You can distinguish them from other jellyfish by their long tentacles that grow from each corner of their bell-shaped body. Boxes can weigh up to 4.4 pounds and can live up to a year in total.

Although this type of jelly is particularly nasty, there aren’t many of them in the waters surrounding Puerto Rico.

What is the most dangerous animal in Puerto Rico?

Although Puerto Rico is pretty safe when it comes to dangerous animals, there are a few creatures you should try to avoid. The most dangerous animals in Puerto Rico are spiders. There are a few species of the eight-legged arachnids on the island that could inject deadly venom into their victim. The deadliest spiders are the brown recluse and the black widow.

Are there Jaguars in Puerto Rico?

The simple answer to this question is no. Although jaguars are often associated with rainforests., these large cats are nowhere to be found among El Yunque’s wildlife. In fact, there are no kinds of large cats in Puerto Rico, but the small domestic cat is doing well on the streets of San Juan!

Are there crocodiles in Puerto Rico?

Although crocodiles are not native reptiles to Puerto Rico, there are some species around the island. They were brought here as pets in the 1960s and released into the wilderness when they grew too big. The most popular reptile is the speckled caiman, whose main area of residence is near the Tortuguero Lagoon.

Reece Toth

Reece is the creator and editor of Travel Snippet. He has visited more than 38 countries over a 10-year period. His travels have taken him through the majestic mountains of Italy, into the cities of central Europe, across the islands of Indonesia, and to the beaches of Thailand, where he is currently living. He is passionate about travel and shares his expertise by providing the best travel tips and tricks to help you plan your next adventure.

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