Puerto Rico  ⏐ Things to Do in Puerto Rico ⏐  Puerto Rico Bioluminescent Bays

Water stars. Glittering, gleaming life illuminating the bay like a mirror of the cosmos.  The Bioluminescent Bays of Puerto Rico are as mysterious as a clear night sky.

Puerto Rico Bioluminescent Bay

You may have seen the magical wonder of bioluminescence in movies such as Avatar, Nim’s Island, and Life of Pi.  You can even head to Disney World to be immersed in a world of bioluminescence, but in Puerto Rico, you can experience the REAL magic and for much less. A tour of a bioluminescent bay is among Top Five Experiences & Best Things to Do in Puerto Rico.

The most popular way of seeing the bioluminescent bays are on a kayak tour, various tour guides offer tours by electric boat.  You’ll glide across the water as day turns to night and surround yourself with the quiet glow of nature’s phosphorescent organisms living in the water.   Nighttime tours can be scheduled for a spellbinding evening.  Keep in mind that like much of Nature, this biological system is fragile, so no swimming or physical interaction with the luminescent organisms is / should be allowed.  This world-class natural wonder is too magical to miss.

How does bioluminescence occur?

When there are high concentrations of dinoflagellates, a microscopic organism, and they come into contact with anything or movement they light up in bright blue light, when you dip your hands in the water, it literally looks like tiny stars running down your hands.

There are few bioluminescent bays in the world, and Puerto Rico was blessed with six, you may read in other places that there are only three but that’s not true, we will not list them for various reasons, the main one is that they are not protected and we are concerned people will flock to them and harm the sensitive ecosystem and balance of the bays.  The following are the most popular and accessible bioluminescent bays in Puerto Rico for tourists, these also have constant higher concentrations of dinoflagellates.

Please Note: Before you book your bioluminescent bay tour, please be sure to read the tips below for the best experience and brightest conditions, and avoid disappointments.

Best Bioluminescent Bays to Visit in Puerto Rico

Laguna Grande Bioluminescent Lagoon – Fajardo, Puerto Rico

Laguna Grande - Puerto Rico Bioluminescent Bay

Visitors vacationing in the San Juan and East Coast of Puerto Rico can book a tour to Laguna Grande, part of Cabeza de San Juan Nature Reserve in the town of Fajardo, about 45 minutes from San Juan and 30 minutes from the resorts in Rio Grande.  You’ll kayak or ride through a narrow mangrove canal that leads to the dazzling bioluminescent lagoon.

Popular Bioluminescent Bay Tours 

Mosquito Bay in Vieques

The Brightest Bioluminescent Bay in the World

Don’t let the common name, Mosquito Bay, prevent you from experience this wonder of nature.  Although this bay was spooky, unfamiliar, and exotic to the first European explorers, the intensity of glowing light is helped by the rocks early settlers threw into the water in their attempt to understand this wonder of Nature, giving the native organisms more places on which to grow and thrive.  This only enhanced the allure of the Bay over the centuries, making Mosquito Bay the most brilliant of the bioluminescent bays in the world.  Mosquito Bay was recognized as the brightest bioluminescent bay in the world by Guinness World Records in 2006.   Residents of Vieques and those that have experienced the magical brightness of Mosquito Bay were tremendously concerned for the bioluminescent bay after Hurricane Maria, to everyone’s surprise, it recovered quickly and it became brighter than ever.  Mosquito Bay has the largest concentration of dinoflagellates and when combined with the low light pollution on the island, it is a spectacle on a Moonless / New Moon night.

La Parguera Bioluminescent Bay – Lajas, Puerto Rico

Lajas  - Puerto Rico Bioluminescent Bay

For many decades, the main attraction of La Parguera, a village in the town of Lajas, was the bioluminescent bay, also called the “phosphorescent bay”.  There are two bioluminescent bays in La Parguera, yet due to poor development planning and the lack of protection laws, and poor enforcement of the rules there are, bioluminescence is poor compared to how magnificent it was 25 years ago.  The use of gas-powered boats, light pollution, and coastal development has diminished the number of dinoflagellates on the water.  We can’t help but feel angry that this precious natural wonder is not protected and may cease to exist completely in the next decades.  For many years the most popular way of seeing the bioluminescent bay was by a boat (gas-powered) with a clear floor, as you can imagine that harmed the delicate balance of the bay.

There are some wonderful tour guides that will take you out on a kayak to the best spots where bioluminescence is brighter, where boats have no access.  You can make a difference by booking a kayak tour of the bioluminescent bay instead of a gas-powered boat.  Aleli Tours offers kayak tours and rentals to do on your own.  (787) 390-6086

Videos of Bioluminescence

Movie Clips of Bioluminescence

Need to Know Facts & Visiting Tips

Puerto Rico Bioluminescent Bays

Help us Protect the Bioluminescent Bays of Puerto Rico

Although swimming is not allowed, sadly some tour operators allow visitors to get in the water, particulary in the bio bay in Lajas.  Please do not wear sunblock lotion, or bug repellants, when in contact with the water, it will harm the delicate balance of the ecosystem.  There are all natural sunscreens and bug repellants without deet that are much safer alternatives both for you and the dinos.

Check the Moon Calendar BEFORE booking your trip

Be sure to check the moon phase calendar.  Bioluminescence is best seen on a moonless night, so the brighter the moon the less bright the lagoon / bio bay will be.  Various tour operators will not run tours on a full moon.  Mosquito Bay is so bright, we’ve seen it very bright even in a full moon sky.

Check for Conditions Before your Tour

A few days before your scheduled tour, call your tour guide and ask about conditions, rain, tides, and temperatures can have an effect on bioluminescence.

What to Wear during a Bioluminescent Bay Tour

Please wear comfortable clothing, long sleeve beach shirts are best to protect you from mosquito bites.

Map - Bioluminescent Bays & Lagoon in Puerto Rico

Puerto Rico  ⏐ Things to Do in Puerto Rico ⏐  Puerto Rico Bioluminescent Bays