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During the day, Laguna Grande in Fajardo looks like other bays along the tropical Puerto Rican coastline. But come nightfall the bioluminescent lagoon glows fluorescent, thanks to pyrodinium bahamense, microscopic plankton that thrive in its shallow Caribbean waters and glow when disturbed.
No, unfortunately, you can’t swim in Laguna Grande during your visit or tour. Swimming is prohibited to keep the bay at its healthiest. The only bioluminescent bay in Puerto Rico that you can swim in is La Parguera, which is a 2.5-hour car drive from Laguna Grande.
...MoreThe bioluminescence bay of Laguna Grande glows with a blueish coloring because of the dinoflagellates in the water. A dinoflagellate is a microscopic organism that uses glowing as a defense when they notice any movement in the water. These short bursts of blue light have drawn tourists to the bays for years.
...MoreYes, you can go to Laguna Grande bio bay without a tour, and it’s legal to go on the water by yourself without a guide. If it's your first time at the bay, you may want to first plan a daytime visit to familiarize yourself with the surroundings.
...MoreThe best time of night to see the effects of the dinoflagellate’s bioluminescence on Laguna Grande is at least two hours after the sun has set when the sky is dark. One of the best times is also during the new moon phase because there won’t be moonlight reflecting onto the water.
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