Visit the Best Bio Bays by Boat, in Puerto Rico.
“Glowing water is far superior to meeting new kids!” The children declared and we listened.
Sailing in Puerto Rico will not be complete without visiting at least one of the three bio bays. It is an amazing experience, there is great anchoring near-by, and you can even swim in one of them (La Parguera, on the southern side of PR).
We sailed along the south coast of Puerto Rico, with our three kids, in March 2022. Even though we were in a bit of a rush to meet other friends on boats, in the Caribbean, I was glad we waited for the perfect night to see the world’s best bio bays.
By the way, the south coast of Puerto Rico is stunning, if you are sailing by. Take a look at places you must visit in our post,
6 Amazing Anchorages Along the South Coast of Puerto Rico (With Notes for Frugal Boaters)
We visited two of the three bio bays in Puerto Rico – La Parguera and Mosquito Bay. For the value of speaking from experience, like a human, I will cover just them.
How to reach the bio bays by boat
Due to the trade winds, sailing west is a lot more pleasant, along the south coast of Puerto Rico.
If you choose to visit the best bio bays by boat, sailing west from the Caribbean, you will have a much better ride.
This way, you will have to visit the best bio bay in the world first (Mosquito Bay), and still have a chance to enjoy glowing water, further west.
We sailed the opposite way.
It is doable, but it takes a lot longer, while waiting for good weather windows.
The best tip we have for you, is to watch the weather closely. Take smaller hops between anchorages, and try to use the calming land effect, at night. Yep, it might mean waking up and leaving right around dawn. By noon, the winds pick up quite a bit.
Want to see what I am talking about – check out our episode with some uncomfortable beating against the Trade Winds, leaving Salinas east:
Vieques, PR – Amazing Beaches and Drama
Anchoring at Mosquito Bay, Vieques
To visit Mosquito Bay by boat, you should anchor as close by as possible, right outside the bay.
This means a very, very small and rolly anchorage, due to wrap-around swell and a bit tricky ground for the anchor to get a good hold.
However, it is the best staging area, with a 10min dinghy ride to visit the bay at night.
Any other anchoring outside of the bay, will mean a longer and more uncomfortable dinghy ride, if at all possible. Those trade winds make the waves quite steep.
It is best to stop at one of the anchorages nearby, enjoy some amazing beach time, and plan to only anchor right at Mosquito Bay for the night of your exploration.
We were a bit seasick at anchor that night, but the visit to the best bio bay in the world was well worth it.
Anchoring by Bahía Bioluminiscente
There is a long reef surrounding Bahía Bioluminiscente, and it offers quite spacious area with great hold.
The anchorage is well-protected spot, behind the reef, while still allowing for plenty of breeze.
The dinghy ride to the bio bay is a bit longer, but it is calm and pleasant. Try taking the dinghy during the day, so you can repeat the route at night.
It is very easy to lose your way coming back to your boat, on a moonless night. That mast light looks like a star.
The anchorage itself is absolutely amazing, great for swimming, snorkeling and lobster hunting (when in season).
In fact, why don’t you see our cool episode, featuring this very anchorage!
Dancing, Junk Food and Lobster (E24)
Helpful answers to common questions
What is a bio bay and why does it glow?
Bio is short for bioluminescent. In the ocean, bioluminescence, is the light produced by microorganisms called dinoflagellates. They live in marine plankton. The blue-green glowing is best seen in bays rich in plankton, with high concentration of dinoflagellates.
Bioluminescence is caused when the plankton is disturbed. It is a defense mechanism of the microorganisms.
To us, it is a brilliant display of sparkles and trails of light, whenever we wave our hand in the water, or a fish swims by.
Why is bioluminescence best in bays?
Water in shallow bays, rich in marine plankton, is more still and segregated. This keeps the plankton concentrated in the area.
In addition, the mangrove plants around the bay provide nutrients and allow the dinoflagellates to multiply.
What’s so special about Mosquito Bay?
It is our fault, actually.
The Spanish settlers in Mosquito Bay were afraid of the “demonic” glow of the water. They wanted to keep the cursed water from spreading into the Caribbean sea. The opening of the bay was narrowed down to a small channel with piles of large rocks.
This created even better living conditions for the microorganisms, which flourished and multiplied.
In 2006 we rewarded our human creativity with the Guiness World Record prize.
Is visiting the bio bays worth it?
Puerto Rico is home to three of the best bio bays in the world. You must visit at least one of them. Our recommendation is definitely the Mosquito Bay, on Vieques, Spanish Virgin Islands.
If you are privileged to be sailing on your own boat, missing Mosquito Bay would be unfortunate.
If you have kids aboard, they will remember that glowing water for the rest of their lives.
If you have kids, who have seen Moana, skipping the bay is kind of punishable.
Are dinghies allowed in the bio bay?
Yes, however, motoring is not. Once you reach the entrance to the bay, do kill the engine and take the paddles.
You can also tow a kayak behind the dinghy and hop in the kayak, once you are in the bay.
Can you see the Bio Bay without booking a tour?
Absolutely.
Do not forget your paddles!
Any of the bays are accessible by dinghy. Once you enter the bay, you must turn off the dinghy motor and paddle.
You can kayak into Mosquito Bay, if you stay at the anchorage right outside the bay.
If you plan to swim at Bahía Bioluminiscente, you might want to reach that via a dinghy.
What is the best time of year to visit the bio bays by boat?
Thankfully, the best time to visit the bio bays, is also the prime cruising time. January through April would be ideal.
This will allow you enough time to not rush and sail away from the hurricane zones.
If you are sailing to Puerto Rico, from the DOminican Republic, you might want to hang out in Salinas, DR, in January/February. That is when the whales stop by.
If you can, try to pick a weekday. Stay away from Spring Break days, it can get busy.
What time of day is best to see bioluminescence?
The ideal time to see the glowing water is at and around new moon. This ensures plenty of darkness and the best show.
The tides, rains, and other factors still influence the plankton, so do call one of the many tours, just to double check if your planned dates will grant you the best possible experience. You do not need to book a tour.
Do keep in mind that the darkest of nights will make the dinghy trip tricky. Bring a flashlight, and do a trial run during the day.
Avoid the sunset hours. Touring agencies usually have a sunset cruise and there might be lots of tourists around.
Besides, the bugs are the worst at sunset!
What to wear when visiting the bio bay?
Something that can get wet. Being on a sailboat, that should come as no surprise.
If possible, wear a long sleeve rashguard, or loose shirt, because the bugs in the mangrove can be annoying.
Avoid the traditional over-the-counter lotions, creams and such. Many are harmful to the microorganisms in the bay. Even a little bit counts, when used too many times, by too many people.
Which Puerto Rico bio bay is best?
It is an old Guiness Record, but it has not been beaten yet (to my knowledge). And it belongs to Mosquito Bay, Puerto Rico.
The concentration of the so called dinoflagellates defines the brightness of the water.
Now, we saw amazing bioluminescent plankton in Los Haitises National Park, Dominican Republic. So, glowing water can be seen in many places.
Bahía Bioluminiscente was pretty cool too.
But Mosquito Bay does beat them all.
Can you swim in the bio bay?
La Parguera is the only one of the three bio bays in Puerto Rico, where swimming is allowed.
Have you heard of snow angels? Try plankton glowing angels!
Ah, ok, speaking of swimming after sunset, in the Caribbean…
Are there sharks in the bioluminescent bay?
Sharks are kind of everywhere, and some can be in the bio bays as well. It is not something to fear, but to be aware of.
Sharks are more likely to be found in the choral reefs, rather than in the bio bay.
What do I need to bring while visiting the bio bays?
Bring a good flashlight, so your dinghy does not end up on the shallow rocks near the entrance.
A regular phone, or a camera will not capture the bioluminescence.
Even though the water is very bright, when the plankton is disturbed, it is not bright enough for a phone camera.
The photos seen online have been taken with professional cameras and are a bit enhanced, for marketing purposes.
There are quite a few amateur photos, which can be found on Google. It is best to use these as a reference.
What about the third bio bay?
The third bio bay is on the east side of Puerto Rico – Laguna Grande. We had enough of jumping up and down waves, sailing east, againt the trade winds, so we decided to not explore the east side, by boat.
As I refuse to contribute to the mass practice of copy-pasting, I am providing a link to another fellow travel blogger, who has written about Laguna Grande, if visiting by land.
This PR local has a nice post about visiting the three bays, by land. Take a look for some tips and suggestions.
A pin, to remind you to visit the Bio Bays, in Puerto Rico
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Your first section should be “What is a Bio Bay?” I can infer the meaning from the text, but a definition up front would be helpful. (Editors are Fun Police of a sort.)
Noted! Thank you very much for the feedback, I do appreciate it.
I will add the section tomorrow.
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