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Just one out of seven full-time bioluminescent bays in the world, the bio bay of Vieques, Puerto Rico is recognized by Guinness World Records to be the brightest. Therefore, a kayak tour through the magical glowing waters of Mosquito Bay is nonnegotiable during any visit to this small Caribbean island.
This phenomenon is quite literally something you have to see to believe, as cameras struggle to capture the color. While I got the blue glow to just barely show up on my GoPro, the quality is laughable. However, I feel that the inability to document everything is part of what makes this mysterious experience so special.
You’ll just have to trust me when I say that this water glows exceptionally bright and that it totally exceeded my expectations. The moonless sky made for perfect conditions, allowing us to also see constellations and shooting stars above! Below, we’ll get into how you can plan the perfect visit to the incredible bio bay of Vieques, Puerto Rico.
Exploring the Otherworldly Bio Bay in Vieques, Puerto Rico
Not fully bought into the hype around the Vieques bio bay or unsure how to plan the perfect trip? We’ll get into all of that below.
The Legend of Mosquito Bay in Vieques
You may be surprised to hear that Mosquito Bay does not get its name from an exceptionally high frequency of mosquitos. Trust that you will encounter those pesky insects in equal measure throughout the island.
In fact, this bay is named after a boat called “El Mosquito” that was captained by pirate Roberto Cofresi. Legend has it that he would hide his ship in this bay to elude authorities.
Why Mosquito Bay?
Vieques’s Mosquito Bay has the perfect conditions for bioluminescence to occur. Mangroves provide essential nutrients and shallow protected waters provide high salinity for light-producing microorganisms called dinoflagellates to prosper. Mosquito Bay happens to have some of the highest concentrations of dinoflagellates in the world and has been protected from development that would cause light pollution.
While Mosquito Bay will give you the most incredible bioluminescence experience, Puerto Rico does have two other bio bays. These do not require the additional step of traveling to Vieques from the main island:
- Laguna Grande: Located in Fajardo, this bio bay is the easiest to visit from Old San Juan.
- La Parguera: While located two hours from San Juan on the west side of the island, this is the only bio bay in Puerto Rico that allows swimming.
When to Visit
It is best to schedule your bio bay tour when the moon will not be out, as its brightness can cause a disappointingly weakened glow. However, it does not necessarily need to be a new moon, as long as the moon does not rise until after your tour. I use this website to check the nightly moonrise schedule.
Oh, and don’t cancel your tour just because it’s raining. The water is so sensitive that even the raindrops will cause little lights to appear. A local compared it to a scene out of Avatar.
Keep in mind that tides and water temperatures can also affect the brightness. If you don’t want to witness anything less than Mosquito Bay at its brightest, it’s best to call a couple days ahead of your visit to confirm conditions will be ideal.
The Experience
Our tour operator arranged for the pick up of all participants around the island, which didn’t take long considering how small Vieques is. The road to Mosquito Bay is in rough shape and is hard to navigate at night, so it’s best to leave the driving to the locals. Plus, it is forbidden to visit the bio bay without a licensed tour company.
All participants paddled into Mosquito Bay in tandem kayaks with glass bottoms. Initially, I saw no glow anywhere until paddling out a little further, where there was suddenly tons of it! It was more than I ever could have imagined, as even the tiniest drop in the water would produce a blue light. As we maneuvered through the darkness, it literally looked like a galaxy was passing by below us.
The water itself was super smooth and waveless, but it appeared pitch black in the moonless night. Mosquito Bay is quite shallow in most spots, at only four or five feet deep. However, there are some areas that are more like 20 feet deep.
Our group mostly stayed together, but we had plenty of space to paddle around and play with the water. At one point, everyone linked kayaks while our guide explained this incredible natural phenomenon, as well as some legends and history of the bay. He also reminded us to look up at the starry sky occasionally, especially as the Geminids meteor shower was going on.
Travel Savvy Tip
Watch out for the sea creatures who call Mosquito Bay home, including sting rays, sharks, and many varieties of fish. You can see the glow of various marine life moving through the water all around you. However, you may see more than the glow of the flying fish.
That right: these pointy-nosed swimmers were jumping out of the water all around us. First we heard them, then we… saw one. My husband and I were the lucky kayak where a fish actually leapt into our boat!
Thankfully, it ended up on my husband’s side and he was able to guide it back into the water. If it was on my side, it may have been us who ended up in the water…
Photographing the Bio Bay
Do you dream of capturing the radiant blue glow of Mosquito Bay during your tour? I’m sure I won’t be the last person to tell you that it’s really not worth the effort.
If you still wish to try, a cell phone camera works much better than a GoPro in dark conditions. However, the result will still be an incredibly far cry from what your eyes perceive.
Also, some multitasking is required to manage your paddle while fumbling around with your phone. Believe me when I say that it’s really, really dark out there. If you drop your phone, you’ll never find it again. In fact, our guide Luis informed us that a phone had already been lost on an earlier tour that evening.
In all honestly, I do not think it is worth it to bring your phone since the results do not warrant the risk of losing it.
Best Bio Bay Tours in Vieques
Technically, in order to run a tour at Mosquito Bay in Vieques, the company must have a license. Two such reputable companies running bio bay tours in Vieques, Puerto Rico are Abe’s and Black Beard (we chose the latter). You can check this page for other recommended companies if these first two are fully booked.
During our tour, we saw a couple unofficial groups that came via a rickety school bus and got stuck in the mud when trying to leave. Aaron and I had earlier watched these groups meet in sketchy dark, isolated areas outside of Esperanza.
In contrast, Black Beard picked us up at an official meeting spot with a spacious and comfortable van. Our driver was full of energy and got us hyped up for the tour before we even met our guides.
What to Wear to the Bio Bay in Vieques, Puerto Rico
For kayaking the bio bay on Vieques, it’s best to wear comfortable athletic clothing that you don’t mind getting wet. Do not apply any sunscreen, lotion, or bug spray, since chemicals in these products can harm or kill the microorganisms that produce the bioluminescence.
If you are worried about bugs, I suggest wearing a rash guard to at least cover your arms as you paddle.
Related: The Ultimate Caribbean Vacation Packing List
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In conclusion, there is nothing quite like visiting the bio bay in Vieques, Puerto Rico. I have seen bioluminescence elsewhere in the United States and it didn’t even come close to the ultra-sensitive glow of Mosquito Bay. You will come away from this otherworldly experience believing that perhaps magic is real after all.
