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bioluminescent bay kayaking

If you’re looking to explore a bioluminescent bay, Puerto Rico is the place to go. There are about five bioluminescent bays globally, and three of these are located in Puerto Rico.

The bioluminescent bays in Puerto Rico include Mosquito Bay in Vieques, Laguna Grande in Fajardo, and La Parguera in Lajas. Each bio bay has something unique to offer, and these can be best explored via a kayak.

Visiting these bays should be on your bucket list this year if you want to enjoy a surreal experience.

Read on to learn more about Puerto Rico’s bioluminescent bays.

What is the Bioluminescent Bay?

The bioluminescent bay, also known as a bio bay, contains many microscopic organisms known as dinoflagellates. These organisms glow in the dark when stimulated by movement. As a result, dinoflagellates will glow when you paddle your kayak through the peaceful waters during your evening tour.

Usually, they produce a neon blue-green glow when you move through the water. Amazingly, everything that interacts with the water also gets a breathtaking shine.

Where are the Bioluminescent Bays in Puerto Rico?

a flag flying by a beach in puerto rico


The three bio bays in Puerto Rico are located around the island. You’ll be able to witness the phenomenon in Fajardo, Lajas, and Vieques Island.

Laguna Grande, Bioluminescent Bay Fajardo

Laguna Grande is located in Fajardo, at the northeast tip of the main island. Unlike the other two bioluminescent bays in Puerto Rico, Laguna Grande is the only destination that is not typically a bay. Instead, Laguna Grande has a long and narrow canal that leads to the bioluminescent plankton.

When you visit this unique ecosystem, you will have the chance to create a trail of light whenever you paddle the kayak through the long and narrow canal.

Don’t leave Puerto Rico without going on an evening tour in this beautiful bay. During the glow-in-the-dark experience, you will be given everything you need. A guide will take you through the tour to ensure you enjoy every minute of it without worrying about your safety.

Mosquito Bay, Puerto Rico Bioluminescent Bay

Mosquito Bay, Puerto Rico, popularly known as magical, is located on Vieques Island. This bay was officially recognized as the world’s brightest bioluminescent bay in 2008 by the Guinness World Records.

The massive number of dinoflagellates in Mosquito Bay occurred due to Hurricane Maria. It is estimated that the bay has around one million to two million dinoflagellates per gallon of water. Above all, the area experiences little or no light pollution, making it the brightest bioluminescent bay globally.

The only way to access Mosquito Bay is by kayak, so the best way to navigate this bay is with a tour.

La Parguera, Bioluminescent Bay Lajas

Located in the southwestern town of Lajas, La Parguera is one of the most romantic destinations in the world. This small fishing village is about a two-hour drive from San Juan, but well worth it.

Unlike the other bioluminescent bays, this is the only bay where visitors can use motorboats. You will be given all the equipment you need during your evening tour to La Parguera Bioluminescent Bay.

You can also snorkel, dive, or take a hike in the beautiful mangroves. Moreover, visitors get the chance to view unique bird species. Better yet, there are several restaurants around this amazing bioluminescent bay. This location also offers the world’s brightest fishing.

Additionally, La Parguera is the only bay in Puerto Rico where you’re allowed to swim in the waters.

What to Know Before Visiting Puerto Rico’s Bio Bays

Of all the bioluminescent bays in the world, Puerto Rico’s are some of the best. Before you head out to explore, here are some tips to help you make the most out of the trip.

Best Way to Explore the Bioluminescent Bays

a group of people rowing a boat in the water

There are many ways to explore the bays, but the waters are best witnessed up close.

With our bioluminescence Puerto Rico tour, you can enjoy the beautiful view of these unique ecosystems from a kayak. Marvel as the water begins to show off with a blue-green glow after each stroke of the paddle.

Best Time to See Bioluminescence in Puerto Rico

To get the most out of the experience, the best time to visit Puerto Rico for bioluminescence is during the hotter periods of the year. This is the time when the dinoflagellates are the most active. Plan your adventure between late spring and early fall.

Best Time of Day to See the Bioluminescent Bay

Since the bioluminescence is most visible in the dark, you should also opt for visiting at night rather than during the day.

Best Time of Month to See the Bio Bays

To make the most of your Bio Bay experience, you’ll want to consider planning your trip around the lunar cycle. When it comes to dinoflagellates, the less light, the better. So, heading out during the new moon offers the best experience.

How to Make the Most of Your Bioluminescent Tour

a person standing next to a body of water

The time you visit isn’t the only thing worth keeping in mind when you go on your Bio Bay tour. You should also take the following into account:


  • Wear comfortable clothing: Since you’ll likely be on a kayak, wear clothing suited to paddling through the waters.
  • Use eco-friendly products: You’ll likely be tempted to glide your hand through the water and watch how the organisms respond. So make sure you avoid anything that could be harmful to the environment. This includes bug repellent, hand cream, and sunscreen.
  • Leave your camera at home: While you’ll want to take pictures of the surreal sight, it doesn’t translate well onto camera. Unless you’re a professional photographer, it’s best to leave your camera behind and live in the moment.
  • Keep an eye on the weather: For the best possible experience, keep an eye on tides and water temperatures. Ideally, you want the bay’s brightness to be above 30%. It’s also worth keeping an eye on Red Tide Alerts.
  • Be respectful of nature: Be mindful of the environment. Do not touch or disturb the water unnecessarily, and avoid making loud noises.
  • Limit light pollution: Avoid camera flashes, phone screens, flashlights, and any other forms of light that could disrupt the natural glow of the water.

Ready To Visit the Bio Bay, Puerto Rico?

If you want to enjoy these breathtaking bioluminescent bays in Puerto Rico, make sure to contact Island Journeys to enjoy a quality, innovative, and socially responsible evening bio bay tour with friendly guides.