Bioluminescent Bay Puerto Rico – 3 Best Places To View

Puerto Rico is a travel location that many consider a must-visit area. It is home to several interesting things, including the biggest radio telescope in the world. Culture is also rich in Puerto Rico – it was the very first settlement that came from Europe toward the United States. It is also a fun location to travel to, with one of the biggest carnivals held in Puerto Rico every February. Of course, these are not all that Puerto Rico has to offer, as the area is also known for its beautiful landscapes and unique beaches that are often called exotic. 

When you decide to take a trip to Puerto Rico, one thing that you have to see is the three Bioluminescent bays in the area. These bays feel magical, with water that lights up at night as you move around, creating a glow-in-the-dark experience that is truly unique.

What Makes A Bioluminescent Bay So Magical?

When we dive into the water at night, we generally expect things to remain dark. The moon might create somewhat of a reflection on the body of water, but apart from that, you would have to put on a headlight or use a flashlight to see your surroundings. Things are a bit different in a bioluminescent bay. 

As you step into these bays, something you will note is that the water around you starts to gain a type of glow-in-the-dark effect. The lights that you see have a green-blueish color and are actually produced by microscopic organisms that are present in the water. These microorganisms are known as dinoflagellates, and they are single-cell organisms that live in water. 

The truth is dinoflagellates are actually found all over the world in the ocean. Millions spread throughout water around the globe, but the concentration of these organisms needs to be exceptionally high in one spot to produce this glowing effect.

Throughout the entire world, there are only five different spots where there is a sufficient concentration of these organisms that create these glow. Three of the specific bioluminescent bays are present in Puerto Rico, and each of them offers a different experience. 

Best Places To View Bioluminescent Bays In Puerto Rico

Why only experience a bioluminescent bay at one spot when you can view these colorful effects in the water at three different locations throughout Puerto Rico. Each of these areas have something unique to offer, which means you will not feel like you’ve seen it all after stepping away from the first location that you decide to visit. We are going to take a look at the three specific spots in Puerto Rico that allow you to see a bioluminescent bay in person.

Mosquito Bay

We start at the site in Puerto Rico that was actually included in the Guinness World Records in the year 2006. Mosquito Bay is located at Vieques, and it has the brightest glow among all of the known areas that are considered to be bioluminescent bays. Experts have found that there are up to two million dinoflagellates in every gallon of water that exists in Mosquito Bay.

This concentration leads to a much brighter glow in the water once the sun goes down. The brightness of Mosquito Bay also increased significantly following Hurricane Maria, when more of these dinoflagellates were flooded into the waters in the area. 

Apart from the illuminating effect in the water, Mosquito Bay also does not have any issues with light pollution, and the waters are exceptionally clean. Many people consider it a natural wonder, even featuring a range of swamps that offers a natural feed for the plankton in the bay.

La Parguera

If your desire is to take a swim alongside these microscopic organisms and see your own body take on a glow, then La Parguera in Lajas is definitely a go-to location during your trip. You can find La Parguera closer to the southwestern region of the Puerto Rico region. This is also one of the areas where motorboats are allowed to enter and exit the bay. 

Something to look out for here is the guided tours. These tours can help you learn more about the effects that these single-cell organisms cause upon movement in the water. These tours will also help you discover more wonders in the local area.

You can also opt for a boat ride, with boats that feature glass bottoms to help ensure you are able to observe these wonders close up. The cost of the tours that are available depends on when you want to go out on the water and the specific operator offering the tour. Most authorized touring agencies in the area give you access to a canoe that you will use to navigate the bay. 

Laguna Grande

The third area where you can experience the bioluminescent effects is Laguna Grande. This one is located at Fajardo and forms a lagoon instead of an actual bay. The lagoon is situated close to San Juan, which is why it is also one of the most popular ones that people visit when they go to Puerto Rico.

Here, the concentration of the microorganisms are also exceptionally high. This ensures you are able to get the full experience when you visit Laguna Grande, even if you are not able to make it to the other two bays that also have these organisms in them. A trip here allows you to observe bioluminescent Puerto Rico beaches at night. 


Puerto Rico has a lot to offer for anyone who wants to travel, especially those who love to experience exotic sites. For many people, the magical experience they have at a bioluminescent bay in Puerto Rico is the top point of their trip. These bays contain microorganisms that actually start to shine when you touch them.

This glow-in-the-dark effect can even be transferred to surfaces that the microorganisms touch for a short period of time. There are three of these bays found in Puerto Rico, which gives you multiple bioluminescent experiences to enjoy during your trip. 

About The Author
Jim is the founder of He loves the Caribbean and wants to share it with everyone he can. He has been traveling in the Caribbean since he was just 18 months old and has seen most of its beautiful beaches and turquoise waters.

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