Puerto Rico Bioluminescent Bay Guide
Daniel Mode
Daniel Mode
Laura Schulthies
Laura SchulthiesPuerto Rico bioluminescent bays are a unique experience that shouldn’t be missed. Puerto Rico is home to three of the world’s brightest permanent bioluminescent bays, more than any other destination on Earth. While bioluminescence can be found in dozens of locations worldwide, from Jamaica to the Maldives, Puerto Rico’s bays offer year-round glow thanks to ideal conditions for the microscopic organisms that create this natural light show. Pictures can’t do them justice as they are truly a sight to see.
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What is a Bioluminescent Bay?
The water in bioluminescent bays can be as bright as stars and light up thanks to millions of single-celled microorganisms called dinoflagellates. The primary species in Puerto Rico’s bays is Pyrodinium bahamense. Whenever these microorganisms are disturbed in the water, from a paddle, a kayak gliding through, or even fish swimming, they produce a brilliant blue-green glow through a chemical reaction involving luciferin and luciferase.
Dinoflagellates can also be found in oceans around the world, but they are far more concentrated in Puerto Rico’s bays, with Mosquito Bay containing up to 2 million organisms per gallon of water. This incredible density makes the glow far more noticeable than anywhere else. Going to a bay with minimum light pollution is essential for the best experience.
When to Visit a Bioluminescent Bay
The three bioluminescent bays in Puerto Rico glow year round. However, the best time of year to see the bioluminescence is during the island’s dry season, from December to April.
Rain can make the waters murky and challenging for the light to shine through, so it’s advised not to go during or after a shower.
The moon phase is the most important factor when planning your visit. The bioluminescence is brightest during the new moon when the sky is darkest. A full moon can significantly diminish or even overwhelm the glow entirely. In fact, tours at Mosquito Bay are prohibited during the three nights surrounding each full moon. Check a lunar calendar before booking, aim for dates within a week of the new moon for the most spectacular display.
The dry season is also the most popular time to visit the island of Puerto Rico, so there are high numbers of tourists around. Be sure to book your bioluminescent bay tour early, especially around new moon dates!
What are the Three Bioluminescent Bays in Puerto Rico
Which of the three bioluminescent bays should you visit on your next trip to Puerto Rico? Here is a little more information to help you decide.
Vieques
Vieques is a beautiful island off the east coast of Puerto Rico, accessible by ferry from Ceiba on the mainland. The ferry terminal moved from Fajardo to Ceiba. The ferry costs just $2 each way, or you can take a small plane from San Juan.
Mosquito Bay holds the Guinness World Record as the brightest bioluminescent bay in the world, a title its held since 2006. With 700,000 to over 2 million dinoflagellates per gallon of water, it is truly a magical place to experience. The bay recovered remarkably after Hurricane María in 2017 and is now glowing brighter than ever.
The tours here are less crowded than Laguna Grande, the island is lovely, and you’re sure to make some great memories. Keep in mind that swimming is not permitted in Mosquito Bay to protect this fragile ecosystem, but you can experience the glow from kayaks or electric boats.
Tours are closed three nights per month due to the full moon.
Check out this excellent Bioluminescent Bay Kayak Trip From Vieques.
Or take a look at all of the other Bioluminescent Tours of Vieques.
Laguna Grande
Located within the Las Cabezas de San Juan Nature Reserve in Fajardo, Laguna Grande is the closest bioluminescent bay to San Juan, about a 45-minute drive away. While it’s about 17 miles from El Yunque National Forest, many tour operators offer combo packages that include both attractions.
Laguna Grande is the second brightest of Puerto Rico’s three bioluminescent bays. You can easily book a kayak tour that takes you through a scenic mangrove canal before opening up into the glowing lagoon.
San Juan is a popular destination, so this is the most accessible bioluminescent bay to visit. However, this also means it can get crowded, with multiple tour groups paddling through the narrow channels simultaneously. Keep in mind that swimming is not permitted at Laguna Grande.
Bioluminescent Tours abound in Laguna Grande! Check out all of these amazing bioluminescent tour options.
Take a look at these tours that stand out for excellence in Laguna Grande. Check out this Bio Bay Kayak Tour In Puerto Rico or this Bio Bay Kayak Tour In Fajardo.
La Parguera
On the southwestern coast of Puerto Rico near the town of Lajas is La Parguera bay, which has been a popular attraction for decades. La Parguera is the dimmest of the three bays due to light pollution from surrounding communities and years of heavy tourist traffic. To help the bay recover, tour operators now use smaller boats with group sizes typically limited to 6 passengers, and the bay closes during the three nights around each full moon.
However, La Parguera has a unique advantage: it’s the only bioluminescent bay in Puerto Rico where swimming is allowed. If floating in glowing water is on your bucket list, this is the place to do it!
Check out these excellent tours La Parguera Bio Bay and Hot Springs Tour or La Parguera Glowing Bioluminescent Bay Boat Tour.
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