A Guide to Puerto Rico’s Bioluminescent Bays

If you’re going to Puerto Rico and wondering if this is something you should try, then the answer is YES and YES! If Bioluminescent Bays aren’t on your list, get one on there! They are Bucket List worthy for sure. One of my top experiences while traveling. Depending on how much you travel or where you like to go, this could honestly be a once in a lifetime thing. You will not be sorry you went!

If you’re like, “yeah that’s great, now what the heck is it?”, sorry I got so excited! Now let me explain.

Bio bays are these amazing bodies of water that happen to have a high concentration of dinoflagellates. These microorganisms will glow when disturbed, which is what gives the bay it awesome looking glow. So basically when you’re moving the water by maybe kayaking through the mangroves or splashing, you will see them light up! Interestingly enough, dinoflagellates are found throughout the ocean. But, there are never a significant enough amount of them to cause such cool things to happen.

There are not many places in the world where you can see this phenomenon, and Puerto Rico happens to have 3 bays where it is visible. So if you are visiting, consider adding this to your list!

Which One Should You Visit?

Puerto Rico has 3 bays to offer: Laguna Grande, Mosquito Bay and La Parguera. The last time I was there, we went to Laguna Grande and it was an amazing time. The water looked spectacular! It was such a unique experience. Some bays will boast better and brighter lights, but it all depends on when you go and how active the bay is that night. Going to any of these will be an amazing experience. We went to Laguna Grande simply because it was closest. Depending on where you are on the island, one of the others might be a better option for you. For instance, if you are on the West side of the island, it would be a trek for you to get all the way to Mosquito Bay, which is on Vieques (an island off the east side of PR). La Parguera would make much more sense as it is in the South West part of the island. As far as I know, that is the only one you can swim in as well. So if that is something that interests you, La Parguera is the one to pick.

What to Expect

If you’ve google searched for pictures of this awesomeness, prepare to be disappointed. The light coming from the water is nowhere near the neon blue that is Photoshopped into most pictures from tour companies. That being said, in person, it is an incredible sight. The unfortunate thing about this experience is that is near impossible to catch with your camera. The dinoflagellates light up so briefly, making any pictures you take of the experience a bit underwhelming. All the more reason to go in person and see it for yourself!

This experience is one for the books. We started kayaking in the darkness, through the water surrounded by mangroves. Although, it was so dark it was almost impossible to see that the mangroves were actually there. Each kayak had a light on the back, which led the person behind you. Otherwise, there was no way to tell where you were going. It was such a peaceful experience, slowly paddling through the mangroves with stars shining above us. It was so serene! Once we got in the bay we were able to paddle around and enjoy the sight. Our guide eventually got us together and explained all the science behind the glowing bay. He even pointed out some constellations in the beautifully visible stars. It was such an incredible experience.

Things to Keep in Mind

Certain things can affect the quality of your experience when visiting a bio bay. There are some things you need to keep in mind when booking your tour. Pollution and light can have a negative affect on the potential glow you can see in the bay. Try to visit near the new moon, when the sky is clear and there is less light to reflect off the water. You can call ahead to see how the visibility has been lately and that will give you a better idea of when to go. Also, always do the latest time available for your tour. This will ensure it is the best conditions for viewing the water and there might not be as many people.

Another thing to remember is to bring bug spray! Although you are out on the water, you are still kayaking though a heavily wooded area. The mosquitoes wont be so bad when you first start kayaking but once you are in the mangroves it will get a lot worse. You don’t want to miss out because you’re itching the whole trip!

Post Maria

With Hurricane Maria rolling through and devastating parts of Puerto Rico, it is so important to go visit. Puerto Rico relies greatly on tourism, and let me tell you, there is so much to do there! From what I’ve read, the bays are recovering and still magnificent to see. Mosquito Bay was hit the worst of the 3 of them, being on Vieques. Since the hurricane, tourism has been down, but gradually increasing. Please don’t hesitate to visit and enjoy what Puerto Rico has to offer.


Have you been to a Bioluminescent Bay? Tell me about your experience in the comments!! I’d love to hear your thought! 🙂

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