Puerto Rico's Bio Bays for Magical Bioluminescence

The first question people usually ask is what is a bioluminescent bay, or a bio bay? Bio bays are rare ecosystems that occur when microscopic organisms called dinoflagellates thrive in numbers large enough (and under the right conditions) to produce a glow-in-the-dark effect when they are stirred to action—say, by a fish, paddle, or human arm. And when they glow, so does anything that comes in contact with them. Visiting a bio bay to experience this phenomenon, is a must-do. 

So when you swim in bioluminescent waters, you glow neon green. It's a surreal, unique experience to visit a bio bay and Puerto Rico has three of them.

Hurricane Maria has affected some of the businesses taking visitors to the bays but they are rebuilding. Be sure and contact them directly regarding availability of services.

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Mosquito Bay on Vieques Island

Let's start with the best of them. There is no bio bay on Earth as bright and mesmerizing as the one in Vieques, truly one of the wonders of Puerto Rico, if not the Caribbean. A swim in these waters, or even a kayak into the calm bay, introduces you to the bright neon green world of the dinoflagellates who live in these waters. Imagine glow-in-the-dark fish flying under the water, kayak paddles splashing to a neon green cadence, or your own body cocooned in an almost alien glow.

It's by far the most recommended bio bay experience on the island and is easily one of Puerto Rico's top five attractions.

You have to take a tour to reach Mosquito Bay. Try

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Laguna Grande, Fajardo

It takes second place to Mosquito Bay in brilliance, but the Laguna Grande in Fajardo is not a bad consolation prize if you can't make it Vieques. Located on the northeast tip of the island, the Fajardo bio bay is easily accessible from the mainland. Tour companies launch from Las Croabas in Fajardo, and the kayak trip takes you through mangrove forests into the lagoon. through mangrove forests into the lagoon.

Once you reach the bay, enjoy its serene, neon beauty. But note that you're not allowed to swim in Laguna Grande. To help keep the bay healthy, swimming is no longer allowed.

Tour companies that visit the Fajardo bio bay include:

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La Parguera

Located off the southwestern coast in Lajas, La Parguera, sadly, comes in a distant third on this list. One of the reasons the other two bio bays have enjoyed health for such a long time is the careful preservation efforts that prohibited, or minimized, access to the bays by boats.

Not so in La Parguera, where over-boating has greatly reduced the bioluminescence of the bay. It is the cheapest of the bio bay excursions, but also the least rewarding. Having said that, a boat ride out into a beautiful night, a glass-bottom boat (if you go that route) and a bit of bioluminescence isn't the worst way to spend a night out in Puerto Rico.

Tour companies that visit the Fajardo bio bay include:

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