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!
Table of Contents
Giant centipede

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.
Spiders

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.
Scorpions

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

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?
Snakes

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.
Lionfish

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!
Mosquitos

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.
Caimans

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 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.
FAQs
The 9 Most Frightening & Dangerous Animals In Puerto Rico? ›
The spectacled caiman (Caiman crocodilus) was introduced to Puerto Rico over 50 years ago with the Tortuguero Lagoon Natural Reserve (TLNR) as its epicenter, where it is now established as an apex predator.
What dangerous animals are in Puerto Rico? ›- Giant centipede: This brightly colored insect can reach 12 inches in length. Its bite is extremely painful. ...
- Spiders and scorpions: Like most islands, Puerto Rico has a high number of spiders, including the brown recluse. It also has a healthy population of scorpions.
The spectacled caiman (Caiman crocodilus) was introduced to Puerto Rico over 50 years ago with the Tortuguero Lagoon Natural Reserve (TLNR) as its epicenter, where it is now established as an apex predator.
What dangerous animals are in San Juan Puerto Rico? ›- Sand fleas.
- Spiders.
- Snakes.
- Scorpions.
- Sharks.
- Caimans.
- Lionfish.
- Giant centipede.
Bats are the only extant native terrestrial mammals in Puerto Rico. All other terrestrial mammals in the area were introduced by humans, and include species such as cats, goats, sheep, the small Indian mongoose, and escaped monkeys. Marine mammals include dolphins, manatees, and whales.
What is a dangerous spot in Puerto Rico? ›Dangerous places in Puerto Rico include parts of cities like Carolina, Bayamon, Vega Baja and some San Juan areas like Santurce, La Perla, Parque de la Palomas, and Puerta de Tierra.
Does Puerto Rico have a jungle? ›El Yunque is the only tropical rainforest in the U.S. National Forest System, and one of Puerto Rico's most beloved natural gems. The park has a very diverse ecosystem, with hundreds of unique plant and animal species, including Puerto Rico's famous coquí frog.
What are the most violent cities in Puerto Rico? ›La Perla is a neighborhood known for its high crime rate and poverty. It has been the subject of numerous documentaries and is often referred to as "the most dangerous place in Puerto Rico". The area is known for its high rate of drug-related crime and gang activity.
Is Puerto Rico known for sharks? ›The Caribbean is a known hot-spot for sharks, and Puerto Rico is slowly but surely making its mark as a “must see” shark research area.
What's the biggest snake in Puerto Rico? ›The Puerto Rican Boa or "culebr" is the largest native species of snake, and one of only three Boidae on the island. It typically grows to a length of 6 or 7 feet, although 12 foot long specimens have been reported.
Does Puerto Rico have bull sharks? ›
Yes, there have been sightings of the Bull Shark in Puerto Rico. Bull Sharks are rare in Puerto Rico, but have been spotted. Bull Sharks are rare to spot. They prefer warm coastal waters but can also live in fresh waters and lakes.
Does Puerto Rico have poisonous snakes? ›There are 11 species of snakes in Puerto Rico and the only one thought to be venomous is the Puerto Rican racer and this snake is not thought to have strong venom. There has been research done on actual bite victims and all of them were released from the hospital within 24hrs.
Are there wolves in Puerto Rico? ›No, Puerto Rico was never within the range of any type of wolf, as most subspecies have adapted well to environments outside the tropics. In fact, there are no canids at all in Puerto Rico.
Are there wild monkeys in Puerto Rico? ›Primates are not native to this country, but the one monkey in Puerto Rico is the rhesus macaque.
Are there wild dogs in Puerto Rico? ›Feral Dog, Wild Dog (Eng.), Perro Salvaje (Sp.), Canis familiaris (Sci.), Native to Puerto Rico; introduced exotic species in the El Yunque NF.
Are sloths in Puerto Rico? ›The Puerto Rican ground sloth, Acratocnus odontrigonus is known from several poorly documented cave excavations in northwestern Puerto Rico. The various species are regarded as being semi-arboreal because of their (relatively speaking) small size and their large hooked claws.
What areas of Puerto Rico to avoid? ›Other spots to avoid at night are the neighborhoods of La Perla (next to Old City) and parts of Puerta de Tierra. Stick to the neighborhoods of Old San Juan, Isla Verde, Miramar and Condado at night, where there are regular police patrols. Should you have an emergency, call 911 as you would in the US.
What is the safest city in Puerto Rico? ›San Juan is the safest city for tourists in Puerto Rico. Although there are some dangerous areas, it features extensive public transportation, some of the best attractions in Puerto Rico, and beautiful beaches. Taking common precautions should be enough to stay safe.
Where do the rich live in Puerto Rico? ›Dorado: Accessible, Upscale, and Safe
If an upscale, livable, walkable area is what you desire in Puerto Rico, Dorado is a great choice. Dorado is one of the wealthiest areas near San Juan, with gated communities everywhere you look.
The vibrancy of Puerto Rican culture comes alive in its dishes, a celebration of flavors that visitors have the opportunity to indulge in. Some of the favorites are mofongo, tostones, pasteles, arroz con gandules, tembleque, and coquito.
Does Puerto Rico have tarantulas? ›
Description. The Common Puerto Rican Brown Tarantula (Cyrtopholis portoricae) is a medium-sized terrestrial arachnid, typically no more than 3 to 5 inches (7.6 to 12.7 centimeters) in length (including leg span), having a dark brown body covered with short, shiny hairs called setae.
How rare is Puerto Rico? ›Puerto Rico population is equivalent to 0.05% of the total world population. U.S. Population Rank: 31th (2021 est.) The population is 4.9 million, although about another 2 million Puerto Ricans live in the USA.
Where is the poor side of Puerto Rico? ›Adjuntas, Puerto Rico has the lowest median household income of any county or county-equivalent in the United States. Per capita income ranges from $24,264 in Guaynabo to $5,943 in Maricao.
What are the blackest cities in Puerto Rico? ›In modern times, most of the music, dance, culinary traditions, and art produced in Loíza is Afro-Puerto Rican and the town has the largest black population on the Island.
What part of Puerto Rico is the poorest? ›Maricao has an extremely high poverty rate, with about 64% of its population living in poverty (Data USA 2019).
Can you swim in Puerto Rico ocean? ›Some beaches have big waves best suited to surfing, and others are as calm as bathwater and ideal for swimming. One thing all the beaches have in common is their accessibility to the public. There is no such thing as a private beach in Puerto Rico.
Is it safe to drink Puerto Rican water? ›Both the CDC and World Health Organization say that Puerto Rico's drinking water is generally safe to drink. Travel advisors expand on that, pointing out that as a territory of the United States Puerto Rico must meet the same standards for drinking water as the States do.
What animals are in the water in Puerto Rico? ›Puerto Rico's rocky shores are home to a vast diversity of organisms such as mollusks (snails, chiton, octopus), crustaceans (crabs, barnacle), echinoderms (sea urchin, cucumbers), cnidarians (anemones, coral), algae and segmented worms.
What is the big frog in Puerto Rico? ›Puerto Rican coquis are one to two inches (2.5 to 5 centimeters) long and weigh two to four ounces (57 to 113 grams). They are one of the largest frog species found in Puerto Rico. As their name suggests, Puerto Rican coquis are native to the forests of Puerto Rico, but they've also been introduced to other places.
What is the GREY snake in Puerto Rico? ›At seven feet long, Puerto Rican boas—also known as yellow tree boas—are the largest snakes on the island of Puerto Rico. They're relatively slender reptiles with a dull brown or gray coloration and dark blotches along their bodies. These snakes are not venomous.
What is the dark brown snake in Puerto Rico? ›
The Puerto Rican Garden Snake is a small animal, typically only reaching a snout-to-tail length of from 12 to 14 inches (30 to 35 centimeters). It has a slender, pencil-like body that is dark-brown in color, with darker lateral markings along its flanks and with whitish cheeks.
Are there great whites in Puerto Rico? ›There are dangerous sharks in Puerto Rico, and there have even been some sightings of Great White Sharks in Puerto Rico – however those are extremely rare here. Yet, there are many other dangerous species in the waters of Puerto Rico that you should be aware of.
Is it safe to swim with bull sharks? ›Divers do not need to worry about scuba diving with bull sharks as they do not pose any threat to us. They are considered among one of the most aggressive sharks due to their characteristics, together with their cousins the great white and tiger shark.
Are there jellyfish in Puerto Rico? ›Moon Jellyfish (aurelia aurita): This is one the most common jellyfish in Puerto Rico. They can grow about the size of a plate. You are able to recognize them by the four circles they have on their bell, or body.
What pets are illegal in Puerto Rico? ›Per the USDA website: All breeds of Staffordshire bull terrier, American Staffordshire terrier, American Pit Bull terrier, and hybrids produced by crossbreeding with dogs of other breeds are prohibited to be introduced or imported to Puerto Rico.
What is the poisonous plant in Puerto Rico? ›Carrasco (Sp.), Guao (PR), Comocladia glabra (Bot.), native, Puerto Rico and Hispaniola.
What bugs are biting me in Puerto Rico? ›Mosquitoes, scorpions, centipedes, flying cockroaches and tarantulas can all be found inside and out in wilderness areas such as forests .
What dog is native to Puerto Rico? ›The Gran Mastin de Borinquen, commonly known as the Puerto Rican Mastiff, is the only breed native to Puerto Rico.
Do jaguars live in Puerto Rico? ›When you think of a rainforest, you might imagine wildlife such as jaguars and monkeys, but you won't find those among El Yunque's animals. The island of Puerto Rico was formed from an underground volcano, so while the island boasts a lot of aquatic wildlife, birds, and amphibians, it doesn't have many endemic mammals.
Are there wild horses in Puerto Rico? ›Known as the island of wild horses, Isla de Vieques is home to about 2,000 Paso Fino horses. Visitors will find the horses strolling on the beach, grazing in fields and by the roadsides.
Does Puerto Rico have alligators or crocodiles? ›
In Puerto Rico, there are no alligators, but you will find a small type of crocodile. This is the caiman, which was introduced to the natural habitats of the island in the 1950s. Since then, due to breeding, pets, and animals released into the wild, there are multiple types of caimans in Puerto Rico.
Does Puerto Rico have Jaguars? ›When you think of a rainforest, you might imagine wildlife such as jaguars and monkeys, but you won't find those among El Yunque's animals. The island of Puerto Rico was formed from an underground volcano, so while the island boasts a lot of aquatic wildlife, birds, and amphibians, it doesn't have many endemic mammals.
Why is there so much crime in Puerto Rico? ›The high poverty rate and inequality between the haves and have-nots make Puerto Rico ripe for crimes. But tourists don't have to worry because most murders and gun crimes relate to gang-related activities. In addition, such crime affects specific neighborhoods where gangs and criminals reside.
What animals have rabies in Puerto Rico? ›Animals most likely to transmit rabies in the United States include bats, coyotes, foxes, raccoons and skunks. In Puerto Rico Mongooses are the principal carriers.
Is there sharks in Puerto Rico? ›The Caribbean Reef Shark is the most common shark in Puerto Rico. This shark is the most common shark you'll find. You can find them swimming around the reefs of Puerto Rico. These sharks are antisocial, and will likely ignore divers and swimmers, so you're safe.
Can alligators cross the ocean? ›There are many things you may encounter when swimming in the ocean. Alligators probably aren't one of them. While alligators can tolerate salt water for a few hours or even days, they are primarily freshwater animals, living in swampy areas, rivers, streams, lakes, and ponds.
What is the largest snake in Puerto Rico? ›The Puerto Rican boa is the largest snake found in Puerto Rico.
Does Puerto Rico have monkeys? ›Primates are not native to this country, but the one monkey in Puerto Rico is the rhesus macaque. Scientists brought these monkeys over in the late 1930s to study them, but they escaped the research facility.
How many murders in Puerto Rico every year? ›In 2021, Puerto Rico recorded around 19.3 homicides per 100,000 inhabitants. The homicide rate registered an increase of 2.8 points compared to the previous year, the largest improvement since 2015.
How many murders in San Juan? ›...
Rankings (2019)
City | San Juan |
---|---|
Country | United States |
Homicides (2019) | 172 |
Population (2019) | 318,441 |
Homicides per 100,000 per year | 54.01 |
Why is Puerto Rico a poor country? ›
The geography of Puerto Rico and its political status are both determining factors on its economic prosperity, primarily due to its relatively small size as an island; its lack of natural resources used to produce raw materials, and, consequently, its dependence on imports; as well as its relationship with the United ...
What are the top 3 animals with rabies? ›The wild animals that most commonly carry rabies in the United States are raccoons, skunks, bats, and foxes. Contact with infected bats is the leading cause of human rabies deaths in this country; at least 7 out of 10 Americans who die from rabies in the US were infected by bats.
What happens if mongoose bite? ›Mongoose teeth may inject bacteria into the bite site. Persons with impaired immunocompetence, for example, individuals with HIV infection, diabetes mellitus, etc are especially vulnerable to such type of infections by bites.
Why are mongoose in Puerto Rico? ›Mongooses were originally brought to Puerto Rico and the Hawaiian islands from Asia to protect sugar cane fields from rats and snakes. This small swift predator preys on birds, reptiles, and amphibians.