Published by Jeremy. Last Updated on January 13, 2022.
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Are you traveling to Vieques for a vacation? Great! You're going to absolutely love this little Puerto Rican paradise just off the coast of the main island.
But while you're exploring the stunning Vieques beaches during your stay, one thing you absolutely must do (and I'm not giving you an option here), is to experience the Vieques Bioluminescent Bay (Mosquito Bay). This wonder of nature is so stunning that we did a tour not once, but twice during our stay on the island and we are certainly glad that we did.
It would be easy for us to say book it, do it (twice), and thank us later, but there are some things you really should know about this attraction before your visit to get the best out of it. Today, we want to share those tips.
Note: This post sadly does not contain photos as it is impossible to photograph the bio bay. Vieques is the perfect place to see them, but it is not the easiest to capture with a camera- but we're going to describe it for you anyway!
Book Your Vieques Bioluminescent Bay Tour for the New Moon
The Vieques Bioluminescent Bay is home to an insane concentration of single-celled organisms that release small bursts of light when agitated. These little cells are in such large concentrations that this bio bay is considered to be the brightest in the world.
That being said, to truly get the best experience in the Vieques bio bay you need to go when it is dark. Very dark. Light from the moon is actually bright enough to completely ruin the experience, so it is recommended to go during a new moon for optimal conditions (tours don't even run the week or so around a full moon, so don't plan your Vieques trip then as you can't go at all!).
We were fortunate enough to be on Vieques on the new moon (this was by design), and we can safely say that having a dark night is a must and we wouldn't have wanted it any other way.
Book the Vieques Bio Bay Well in Advance
As the bio bay tours are the most popular experiences on the island, you absolutely must book this one in advance well before your trip. Our guides told us many stories about people who showed up to the island to book a tour last minute and couldn't go due to capacity limitations, and we would've been absolutely devastated to travel all that way and not do this amazing experience.
So, now that we have the general tips out of the way, we wanted to share more about what the experience is like as it is impossible to get photos and the promotional photos are, well, not right in the slightest!
Balls of Light Everywhere (That Are Best with a Glass Bottom Kayak)
I'm going to start off by disappointing you- the Vieques Bio Bay experience is nothing like what the promotional photos look like. All of the photos we saw showed a blue aura around the water and kayaks, implying that you will have a halo-esque light around you while you're in the bay.
The Vieques bioluminescent bay is nothing like this at all.
The best way to describe the bio bay, in our opinion, is like Disney fairy dust (think Tinkerbell). Hundreds upon hundreds of sparkling dots of light that briefly glow around objects in the water.
If you put your hand in the water, you'll be covered by dozens of little balls of light such that you see the outline of your hand perfectly despite it being pitch black. If you smack the water with your oar, you'll see the outline of fish swimming off in the distance. If you are lucky enough to see a turtle, ray, or shark in the water, you'll see its general outline perfectly even at a bit of a distance as long as the water is not disturbed. (Our guide spotted a ray, but sadly we missed it.)
During our tour we took two kayak tours, one with a regular kayak and one with a glass bottom kayak, and the glass bottom kayak offered a different experience as when you row through the water the balls of light shine on the glass panel as they glide along.
In this instance, Disney fairy dust is probably not the best way to describe it, but it rather looked more like light speed in Disney's Star Wars saga where the stars (or in this case light from the single celled organisms) zoom past you at fast speeds.
Yes, it is insanely cool, and yes, I'm very upset we couldn't photograph it (this is an understatement). But everyone we spoke to said this is the most apt description, so we think it is a good start so you know what you're getting in to.
Tips for When You're Out on the Water to Play With The Light
Now, I know you're excited, but we have more.
The funnest part about the bio bay tours is that you are able to goof off as much as you want to try and think of novel ways to get the water to light up. We tried everything we could think of, and have a few recommendations for you to try (plus a few more we think could be good, but didn't get to try for lack of special objects).
So while you are out on the bio bay, be sure to try the following things to see what happens!
- Go as fast as humanly possible in your glass bottomed kayak.
- Go extremely fast and do a hard bank (bonus points- get behind someone who does it to watch their wake).
- Put your hand in water and spread your fingers out wide.
- Put your fingers in the water and move them around when going really fast.
- Slap oar on the water to scare fish (this one never gets old, poor fish).
- Do an Iron man where you hold your hand under water in a fist and open your hand out fast with a forward thrust.
- Dip your hand in the water, pull it out while it is wet (palm up fingers flat) and blow on it really hard to get the water to spray off.
- Dip your hand in the water, pull it out pointed up quickly and let the water trail down your arm.
- Do you have hairy arms? Put your arm in as deep as you're comfortable with and move it around. (Is still cool without hairy arms too)
- Take an empty water bottle and fill it up to shake it (don't bother saving it for later to try at your hotel in the dark, though.)
- Put your oar really deep in the water when staying still and move it around gently.
- Bring a clean squirt bottle to spray into the air. (We did not get to do this, but I suspect it would be amazing.)
But Seriously, Book Two Tours
Really, when it comes down to it, the Vieques Biolumeniscent Bay is one of the most impressive natural wonders you will ever see. So much so that the brief one night tours are simply not enough.
If you are like us, you'll definitely want to book the tour two nights in a row because, as we found out from other guests, no other biobay in the world comes close. So if you make the trip down to this little island paradise in Puerto Rico, do yourself a favor and book this one twice. You won't regret it.
Note: be sure to wear non-DEET bug spray during your visit. The region is full of mosquitos, but DEET can hurt the organisms in the water, so be sure to use alternative protection this night. Finally, do not bother trying to take photos with or without a flash. It won't work and all you'll do is piss off those around you with a flash. Trust us, don't be that person.
About the Author: Jeremy is a full-time travel writer based in Pittsburgh and primary author of this site. He has been to 70+ countries on five continents and seeks out new food, adventure activities, and off-the-beaten-path experiences wherever he travels.