Bioluminescent Bays
A quick Google search will tell you that there are only five bioluminescent bays in the world and that Puerto Rico has three of them. As far as I can tell, this may be true as long as: The body of water must be a bay, and it must be bioluminescent year-round. I have been to all three locations in Puerto Rico. Two are located on the exact opposite sides of the island – one in the southwest corner, the other in the northeast. The other is on the south side of Vieques Island.
The single most important part of making your visit a great experience is when you go. Check the moon chart online. The fuller the moon gets, the less worth it it is to go. Going on or near the new moon is your best bet. Also, going before moonrise can be a factor worth considering. Swimming in the water is prohibited in all three bays. Sunscreen and bug repellent are especially damaging to the microorganisms that create the bioluminescence.
Mosquito Bay is often considered the crown jewel of Puerto Rico’s bioluminescent bays. I agree that it is brightest, but not much brighter than Laguna Grande. You’ll have to wade through some gross mud to get to the water. I’ll always remember paddling through the dark water, watching fish light up beneath me, outlined perfectly in greenish light as they swam away from my board. The bioluminescence outlines the marine life so perfectly that I can occasionally identify what is swimming beneath me. Watching the perfect, glowing outline of a nurse shark glide away was one of the most magical moments I’ve had in Puerto Rico.
To get to Laguna Grande, you’ll need to paddle down a long channel winding through mangroves. I had a great time navigating the dark channel. We were rammed once by a kayaker in a tour group. The channel is very dark, so you’ll need a light if you are not part of a tour group. A headlamp is ideal. As the name suggests, the bay is big. There are buildings on a hill nearby with bright lights, which make the bioluminescence less visible. Some areas are brighter than others. Watching the water light up with every paddle stroke is an unforgettable sight.
The bioluminescent bay in Lajas, within the Parguera Natural Reserve, has its own distinct character. Unlike the other bio bays, visitors arrive by motorboat and watch the water glow as swimmers stir up the bioluminescence. The glow itself is beautiful, but for me it feels less immersive than paddling through the light on my own. Still, the shimmering water under the night sky makes for a memorable sight.
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