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Discovering the bioluminescent bay in Puerto Rico

The bioluminescent bay in Puerto Rico is also known as « bio bay ». It is one of the top tourist destinations on the island. Out of five bioluminescent bays in the world, Puerto Rico is really lucky to host three of them. Two are located on the main island, in the municipalities of Fajardo and Lajas. And the last one but not least is the most famous one. Mosquito Bay is located on the southern coast of Vieques island.

What makes the bioluminescent bay water glow?

It’s always a question that comes to our mind when we read for the first time about the bio bays in Puerto Rico. The reason for a bioluminescent bay to glow is because of some single-celled organisms living within the lagoon. The best way to illustrate them is to imagine fireflies within the water. And as a chemical reaction, when touched or moved, those amazing microorganisms emit light. That’s why they get active when you are sliding on the water, surrounding your kayak and paddles with a « magical » light.

For sure, a unique experience you won’t forget. So if you are planning a trip to visit « Isla del Encanto » besides enjoying the best beaches in Puerto Rico (Article in Progress) you cannot miss your chance to enjoy such natural beauty. Pick one, out of the 3 bioluminescent bays they are in PR, and come play with these living microorganisms called dinoflagellates.

Bio Bays in Puerto Rico are fragile ecosystems

These single-celled organisms called dinoflagellates are fed by their natural ecosystem. Mainly composed of red mangroves, fishes, dead leaves, iguanas, and a balanced quantity of clear and salty water. Red Mangroves play a significant role, sprouting a knot of roots that discharge microscopic organisms into the water giving basic nutrients to dinoflagellates. Change one of those numerous factors and this fragile ecosystem may not allow the bioluminescent bay to glow anymore.

Back in September 2017, after Hurricane Maria, a series of sargassum waves have harmed the bio bays and other protected areas in Puerto Rico. The challenge with this type of seaweed is that when they die, they take out the oxygen from the water and harm other sea life. As a result, the population of dinoflagellates decreased drastically and for a short period of time, the bioluminescent bays in Puerto Rico did show no light.

Where are the 3 bioluminescent bays in Puerto Rico?

Laguna Grande in Fajardo is the closest to San Juan

Laguna Grande is the second most active bio luminous bay in Puerto Rico. Only one hour driving from San Juan, this bio bay located in Fajardo is surrounded by the natural reserve of « Cabezas de San Juan ». Its proximity to the capital makes it the most easily accessible bioluminescent bay on the island. Within the water, you will find out a thriving and active concentration of glowing microorganisms. Before arriving at the lagoon you will have to paddle through a long and narrow canal. So if you are looking for some unique and adventurous excursions by night, here you go!

Mosquito Bay in Vieques is the most glowing one

On Vieques Island, you will find another bioluminescent bay and within its water the highest concentration of dinoflagellates. Also known as « Mosquito bay » it is the most glowing bay on earth! Beware, this naming is coming from nowhere, there is also a high concentration of mosquitos in this lagoon. That said, the best way to explore it will be to go on a kayak tour. But unlike the bio bay in Fajardo, you won’t have to paddle through a long and narrow canal. More protected from city lights pollution, you should enjoy the amazing night scenery.

The third bioluminous bay in Puerto Rico is in La Parguera

Lajas is a municipality of Puerto Rico located between Cabo Rojo and Guánica, on the southern coast of the island, facing the Caribbean Sea. The bio bay in La Parguera, also known as « Bahía Fosforescente », is the least active bioluminescent bay on the island. But if you are visiting the south of the island, don’t miss your chance. Get a seat on one of the many boat trips and enjoy the tour on the water.

How to preserve the bioluminous bays in Puerto Rico?

Human activity has a negative impact on the bioluminescent bay. The more we reduce our footprint within the lagoon, the better this fragile ecosystem will be. But what does it means? How can you help the population of the microorganisms to grow and be active?

Being aware of your impact is the first step to help. Then choosing to go on a kayak tour is better than a boat trip, especially the ones with gas motors. Avoiding any chemicals on your skin such as bug repellants, sun creams, lotions, etc…

During your tour please refrain from throwing any type of object, food, or trash on the water. If you decide to shoot a picture or a video with your phone, please be really precocious. And by the way, your camera might not manage to catch any of the beauty you will be experiencing in real life.

My personal bioluminescent bay experience in PR

Back in 2018, I was lucky enough to discover the bio bays, both in Vieques and Fajardo. And to be honest, before going I was a bit skeptical, maybe like you are. But I am a curious person and I have decided to give it a shot. What a surprise it has been, when the water started to glow. I couldn’t believe it, it was a mix of daydreaming and magic.

From this moment, my best memory is a stingray fish. Paddling the kayak, we followed it for a few seconds while its entire body was glowing. That night in the bioluminescent bay, I felt like being in a Hayao Miyazaki mangas. Maybe I was lucky, but all I want to share with my personal bio luminous experience is that bioluminescent bays in Puerto Rico are real beauty. And it is a wonderful moment to experience!

Choose one of the many types of tours

Reserve kayak excursions in Laguna Grande or Mosquito Bay.

In my opinion, kayak excursions are the best way to discover a bio bay. You will find many companies offering kayak tours, both in Fajardo and in Vieques. Of course, it is always better to book in advance but going directly to the pier around 6 pm should be no problem. There you might find available tickets, around 50$ per person.

Take it easy and take a tour with an electric boat in Fajardo

Because you will have to paddle through a long canal before getting to the lagoon, kayak tours in Fajardo can be a bit demanding. So for those who want to take it easy, just know that an electric boat tour does exist. Up to 6 seats it is also a nice way to experience the magic of the bio bay in Fajardo. From Monday to Friday this guided tour last 1h15min and cost 52$ per person.

Book a boat trip and enjoy the bio bay in La Parguera.

In la Parguera bioluminous bay, the only way to go is with a boat. Many companies operate different types of boats from 6 seats to 30 seats. One of them even offers a much bigger boat, that can seat up to 150 people. I guess it is also a nice and different way to explore the bio bay, spending a part of your night on the water. Cheaper than a kayak tour, it cost from 9 to 12$ per person.

Frequently Asked Questions about the Bio Bay

Where are the 3 bioluminescent bays in PR?

The first bio bay is in la Parguera on the southern coast of Puerto Rico. Mosquito Bay on Vieques Island is the most famous and glowing bioluminescent bay. The third one is the closest to San Juan. Find out where in our guide.

Where are the 5 bioluminescent bays in the world?

If you red our « Ultimate guide on the bioluminescent bays in Puerto Rico » you already know that 3 of them are in PR. Now let’s find out where are the two other ones. Luminous Lagoon is in Jamaica and Halong bio bay is in Vietnam.

Where is the bioluminescent bay in Puerto Rico?

You will not find one but three bioluminescent bays in Puerto Rico. The most glowing one is located on Vieques island. One hour driving to San Juan you will find Laguna Grande in Fajardo. Discover the third bio bay in our guide.

Can you swim in the bioluminescent bay in Puerto Rico?

The short answer is no. You cannot swim in the bioluminescent bay in Fajardo. Swimming is also forbidden in the most glowing one, Mosquito bay. Read our guide to the bio bays in PR and get to know if you can swim in the third one.

Is there a bioluminescent bay in Culebra?

I love Culebra but there is no bioluminescent bay there. The closest bio bay to Culebra is on Vieques island. They are great places to discover on your road to Culebra. Find out where to stop in our « Best guide to bio bays in Puerto Rico ».

How many bio bays are there in the world?

There are 5 bio bays in the world. In Jamaica, you will find a bio bay called the Luminous Lagoon. The second one, Halong Bay, is located in Vietnam. The 3 other ones are all spotted in Puerto Rico. Discover the exact locations on our website.

What is a bio bay?

A bio bay is a protected lagoon surrounded by a fragile ecosystem. Within the water, you will find out some microorganisms producing lights. Learn how and why they do this on our page dedicated to the bioluminescent bays in Puerto Rico.

Where is the bio bay in Puerto Rico?

You should ask « where are the bioluminescent bays ». No less than 3 glowing bays are in Puerto Rico. Two are located on the main island and the third one is on Vieques. Get more details and info on our website dedicated to the bio bays in PR.

How many bioluminescent bays are in Puerto Rico?

Puerto Rico host 3 bio-luminescent bays. 2 of them are on the main island. The other one is in Vieques. Before going please read our complete guide to the bio bays in PR. Get useful tips about Laguna Grande, Mosquito bay, and La Parguera.

How many bioluminescent bays are in the world?

5 bioluminescent bays have been discovered in the world. Some of them glow more than others. Find out in our guide where is located the most glowing bio bay on earth. Going there is a magical experience you won’t forget.

What is the best bioluminescent bay in Puerto Rico?

That’s a tough question. Closest to San Juan the best bio bay is in Fajardo. I love to paddle the long and narrow canal to the lagoon. If you are visiting Vieques, Mosquito bay is the most glowing bioluminescent bay in Puerto Rico.

What to wear to explore a bioluminescent bay?

To explore a bioluminescent lagoon one pair of shorts, one t-shirt is the classical clothes. A kayak tour on the water last 2 hours. So take clothes that can get wet. Read our guide and find out the best shoes to take on a bio bay trip.

Where are bioluminescent bays located on earth?

They are five bioluminescent bays on earth. One in Jamaica is the luminous lagoon. One in Vietnam is Halong Bay. The three other bio bays are in Puerto Rico. Find out where exactly and plenty of info by reading our guide about bio bays in PR.

Which bioluminescent bay is best in Puerto Rico?

Tough to answer. I would say it depends. If you are in San Juan the bioluminescent bay in Fajardo is best. But if you plan to go to Vieques anyway, Mosquito Bay becomes the best option. More about bio bays in Puerto Rico in our guide.

Why does the bioluminescent bay glow?

Because of some microorganisms within the bioluminescent bay water. Their scientific name is dinoflagellates. When you touch them they create a light with a chemical reaction. More about it in our guide. The bio bays in PR.