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Best Night to Do the Biobay Depends on the Moon

You can skip this intro and jump straight to the calendar →


When you visit Puerto Rico, one of the must-do things is a trip to one of our bioluminescent bays (or bio-bays). Whether you go to Laguna Grande in Fajardo in a kayak, Laguna Grande in an electric boat, Laguna Grande on a walking tour, Mosquito Bay in Vieques, or La Parguera in Lajas, you’re sure to have an experience that you will never forget.

In case you want to try to capture some memories of the biobay in pictures, we’ve written a primer for taking photos in the biobay. Note that you’ll need a very steady boat, and a camera with lots of manual settings — you’ll need to be able to control the length of exposure, the aperture setting (f-stop), and the ISO/ASA film speed setting.

The health of the biobays is measured by the number of dinoflagellates per unit of water. That measure translates into how "bright" the bay will be. Mosquito Bay is the brightest, La Parguera is the least bright. The Department of Natural Resources has taken steps to maintain and improve the health of Laguna Grande.

In any case, the biobay is best experienced on a cloudy or moonless night. While we can’t predict if there will be clouds, we can do a pretty good job of predicting the phase of the moon and the time the moon rises and is overhead. Those are the main factors that come into play. In general, it’s best to avoid the 5 to 8 nights prior to the full moon and a day or two after.

The better bio-bay tour operators will be able to tell you in advance if the night you’ve chosen will be a good night, with regard to the phase of the moon and moonrise. Many operators will not even conduct tours on less-than-optimal nights. Others will bring a tarp to use to block out the moonlight.

To help you with your planning, we’re providing the calendar below which indicates the new and full moons, and our opinion of which nights will be better or than others.

     New Moon





     Full Moon

     Best Early, Good Later

     Good Early, Fair Later

     Fair Early, Bad Later

OCT 2021
1 2
3  4 5 6 7 8 9
10 11 12 13 14 15 16
17 18 19 20 21 22 23
24 25 26 27 28 29 30
NOV 2021
1 2 3  4 5 6
7 8 9 10 11 12 13
14 15 16 17 18 19 20
21 22 23 24 25 26 27
28 29 30
DEC 2021
1 2 3  4
5 6 7 8 9 10 11
12 13 14 15 16 17 18
19 20 21 22 23 24 25
26 27 28 29 30 31
JAN 2022
2 3  4 5 6 7 8
9 10 11 12 13 14 15
16 17 18 19 20 21 22
23 24 25 26 27 28 29
30 31
FEB 2022
1 2 3  4 5
6 7 8 9 10 11 12
13 14 15 16 17 18 19
20 21 22 23 24 25 26
27 28
MAR 2022
1 2 3  4 5
6 7 8 9 10 11 12
13 14 15 16 17 18 19
20 21 22 23 24 25 26
27 28 29 30 31
APR 2022
1 2
3  4 5 6 7 8 9
10 11 12 13 14 15 16
17 18 19 20 21 22 23
24 25 26 27 28 29 30
MAY 2022
1 2 3  4 5 6 7
8 9 10 11 12 13 14
15 16 17 18 19 20 21
22 23 24 25 26 27 28
29 30 31
JUN 2022
1 2 3  4
5 6 7 8 9 10 11
12 13 14 15 16 17 18
19 20 21 22 23 24 25
26 27 28 29 30
JUL 2022
1 2
3  4 5 6 7 8 9
10 11 12 13 14 15 16
17 18 19 20 21 22 23
24 25 26 27 28 29 30
AUG 2022
1 2 3  4 5 6
7 8 9 10 11 12 13
14 15 16 17 18 19 20
21 22 23 24 25 26 27
28 29 30 31
SEP 2022
1 2 3
 4 5 6 7 8 9 10
11 12 13 14 15 16 17
18 19 20 21 22 23 24
25 26 27 28 29 30

     New Moon





     Full Moon

     Best Early, Good Later

     Good Early, Fair Later

     Fair Early, Bad Later

Updated 16-Oct-2021 03:28am UTC. assumes no responsibility regarding your safety when participating in the activities described in this article. Please use common sense! If your mother or that little voice in your head tells you that you are about to do something stupid … then don't do it! Read more about Safety →

Comments & Discussion Leave a Comment »

There are 419 comments on this article. Add to the Discussion »

As far as I know, the minimum age for the kayaks is 6 years old. I am not 100% sure if the electric boat is going, but they have an age minimum of 3 yo. Even so, I am not sure if a child would appreciate the natural beauty of it.

Comment by Gwenn on 30 Apr 2021

My family and I will be PR May 11th - 15th, and I would love to see the Bio-bays. I have 2 small children (ages 5 & 2) - would it be safe and worth it to go?

Comment by Susan Poruthur on 29 Apr 2021

Yes, I am with you, I believe it will be fine for viewing, especially the first tour. But each tour company uses their own calendar/schedule. This is just what I think based on moon rise and how bright it is and where it is in the sky during tour hours.

Comment by Gwenn on 10 Apr 2021

Hello, thank you for this very useful calendar tool! I am planning on doing the Biobay in Vieques on 4/29/21, and I called a tour operator to book it and they said that they would not be taking tours out until 5/1/21 because of the full moon earlier that week. I am confused as I know that the full moon is 4/26/21, and on 4/29/21 the moon is scheduled to come out at 9:44pm, so I just wanted to confirm that you think 3 nights after that should still be good conditions, especially if it was an earlier tour? Thank you!

Comment by Greg Ayscue on 09 Apr 2021

It really depends on what you like to do before/after. We like the early trip since we like to see the mangrove animals a little, but then dinner is late (and we are wet when we eat after) So we might do a late lunch then the trip. Or, you eat dinner normal time, while dry, do trip but drive home late. Parking is a little tricky to get at later trip time around the tour point. But either one is equal tour-wise.

Comment by Gwenn on 09 Mar 2021

Hello! I am having a hard time deciding which tour to choose (Early or late) on April 10, 2020. I see that Apr 11 is a new moon day so it will be a good time. However, can you please suggest which of the either times would be better for viewing *5.45 or 8pm)?

Comment by Nivedita on 09 Mar 2021

A clear kayak is not a must but..... we just did a clear kayak trip in Vieques and it was spectacular. We felt it was worth the extra money. The front person gets the best of it- looked like Star Trek Warp Speed- stars zooming around and under you. Guy in back can just see on side and under, still cool he said!

Comment by Gwenn on 13 Aug 2019

Saludos! Would you say a clear bottom kayak is a must, or a regular kayak would do? Thanks!

Comment by Claudette M on 11 Aug 2019

yes, end of August is perfect. But capturing the glow is very hard (almost impossible) from a moving kayak, due to the slow exposure needed.

Comment by Gwenn on 03 Aug 2019

Hello, so is it a best time do do Bio by end of august? :) also, how am I gonna capture the glowing? we have Go Pro new edition black and sony a5100 . are these going to work? or we have to buy a special camera? thanks! Saludos

Comment by Joanna on 02 Aug 2019

The bays vary in deepness, I believe ranging from about 3-10 ft. But with a life jacket and trained guides, it is safe. Not like there are waves or rip currents there. Yes, there are weight limits for the kayaks, I assume they vary by company. I see about 250 lbs each person, max abut 485 pounds for 2 person kayak. Could be more or less, you would have to ask for specifics from the company u choose.

Comment by Gwenn on 18 May 2019

Are the kayaking tours into the biobays safe for individuals who cannot swim? I am aware that you get life jackets etc, but I'd like to get a sense of how deep the water is. Also, is there a weight limit for the kayaks? Thanks in advance!

Comment by Danielle on 18 May 2019

I don't know for sure, but possibly yes. You would have t0 check with the companies directly.

Comment by Gwenn on 26 Apr 2019

Do they have bio bay tours on Dec 24th? It seems like a good day to go according to the moon calendar this year.

Comment by Christy on 25 Apr 2019

yes, exactly. There are usually a couple trips a night...early trips and later trips. As the moon gets higher in the sky, viewing gets worse. So some nights it is best to go earlier.

Comment by Gwenn on 19 Apr 2019

What does it mean in the moon calendar suggested days when it says “best early, later good”? Are they saying that the earlier time 7ish would be great viewing and the later time 9ish would only be good viewing?

Comment by Milena on 19 Apr 2019

Legally, one can do it on your own, but you would have to find a kayak to rent elsewhere and transport it somehow. And then know where to go and where to park out of the way of tour buses etc. It is not recommended.

Comment by Gwenn on 21 Dec 2018

Is it okay to go on our own and just rent kayak from there? Or not allowed and only group tours are allowed?

Comment by Summer on 21 Dec 2018

all the tours go to similar areas, the leader of the group will look for the brightest glow or the darkest areas for best viewing.

Comment by Gwenn on 26 Nov 2018


Comment by CARLITOS WAY on 25 Nov 2018

Yes, it is a flat walking boardwalk. They take you around in a trolley, so a few steps here and there.

Comment by Gwenn on 16 Sep 2018

We will be in PR on Nov 30th and would like to take the walking tour at L. Grande. Can you tell me if the walking area is level. Ok for seniors?

Comment by Dee Mass on 12 Sep 2018

yes, the moon will not be rising until 10:24pm on the 24th, so the usual tours should be over by the time the moon is much over the horizon, so viewing should not be affected much. La Parguera is a long drive from SJ, but yes, you can swim there and they go on Sundays. It can be hit or miss with the bays, depending on weather conditions and natural phenomenon and which tour you go with (large boats can't go deep into bay). Could be bright or not. My thoughts....depends on you- I hate driving late at night- depending on whom you go with, those tours can run late. But, you know the details, so if you are ok with the drive....go for it!

Comment by Gwenn on 03 Sep 2018

We will be in Puerto Rico March 16 and March 24, 2019. Full moon looks like it is March 21. I am confused because if you look at a lunar phase calendar, it still looks like the moon will be mostly full on March 24, but you have it as a good day. We were thinking about going to La Parguera because we heard you can swim in only that bio bay. I heard it takes about 2 1/2 hours to drive from San Juan, correct? It is a Sunday but it looks like some tours go out then. Your thoughts?

Comment by Dee Magg on 31 Aug 2018

Comment by Gwenn on 23 Aug 2018

We will be in San Juan on September 15th. We want to see this but have no idea where to go or who offers transportation / tours? Can you help with that? There will be 5 of us.

Comment by Patty Williamson on 23 Aug 2018

Dear friends, Congrats for your website! It is an excellent tool for travelers. My only concern is about some info you offer on it. We have operate La Parguera Bio Bay for 30 years. La Parguera is home base for the only Marine Lab part of the University of Puerto Rico and they do research on the Bio Bay very often and the results are always very positive and our bio bay is very healthy. Even after the Hurricane Maria our bio bay was glowing as always and even better without power!! We have been operating since October 12, 2017, less than a moth from Maria and Thanks to God La Parguera was the less affected area of Puerto Rico! You are doing a great job and thanks!!!

Comment by Captain Kiko Doitteau on 11 May 2018

You will need to contact a tour company directly for specifics. At least one company goes out Sunday, all go Monday. Most provide transportation from may have to get from Santurce to Condado/Isla Verde area. All the companies for Laguna Grande biobay are in this article:

Comment by Gwenn on 08 Mar 2018

I would like to kayak on a biobay tour for 2, possibly more than 2 persons, on march 18 or 19. Moon looks good. Will it be open? What is the phone number to book a spot and what is the price? Time the tours start? Will be staying in Santurce. What is the best transportation to Fajardo? Thank you so much.

Comment by MOLLY HARRINGTON on 08 Mar 2018

Yes, according to this calendar, those nights are great viewing. On;y the Fajardo biobay is open, so plan on going to that. Tour company contacts are in this article:

Comment by Gwenn on 09 Feb 2018

Dear Puertoricodaytrip Team, I wonder if on Feb 16th (Friday) in Farjado or Feb 18th (Sun) in Vieques is a good option to see Bio Bay? My friend and I will be in Puerto Rico from Feb 15th to Feb 19th. Not very sure if these locations are open to visitors now. If you have any suggestions, kindly let us know. Really appreciate for any suggestions. Looking forward to hearing you.

Comment by Ruth Yang on 07 Feb 2018

Well, there are not many tourist now, so you probably don't have to rush to book! Yes, your dates are tough with the moon. I assume you are staying on the main island of PR, not Vieques. Fajardo biobay is glowing well and all the kayak companies are going out. I heard the electric boats may restart in March. The 25th would be your best bet (1st trip out- 6:30 p or something). But it is a Sunday and only a couple companies go out. The 26th 1st trip would be my next choice. Both dates would be best if there are clouds! Company contact info at bottom of this article:

Comment by Gwenn on 07 Feb 2018

Hi there - love your facebook page with all the updates recently! (We have a trip planned for Mar 24-30, and we kept it booked partly because of your info) We wanted to see bio bay, but I see the moon is not on our side, also not sure what places are open yet. Do you have any advice for who to talk to or where to go? Is it something to try and book ahead of time or keep an eye out for clouds and try to go that way? Thanks

Comment by Jonathan on 07 Feb 2018

We usually use Kayaking Puerto Rico, we have never had a bad experience with any of their tours. The biobay closest to OSJ is in Fajardo. Most tour operators will offer transportation for an additional cost. Or you can drive yourselves.

Comment by Gwenn on 04 Feb 2018

We are coming to PR on March 8, 2018 and were hoping to do a bio-tour. We are staying in old San Juan. Which bio-tour would you recommend, that isn't too far from Old San Juan?

Comment by Tracy Lindsey on 03 Feb 2018

Usually I would say no, but it has been such a bad year, it is possible one of the companies will go out. If you can't get the 25th, go on the first tour on the 26th.

Comment by Gwenn on 17 Dec 2017

We will be there on Christmas night (Dec. 25, 2017). Will there be any tours operating for the bay? The other nights look like they won't work because of the moon phase - do you suggest not doing a tour on a "bad" night?

Comment by Suzette Alles on 11 Dec 2017

I assume your trip was cancelled. Sorry for the delayed response.

Comment by Gwenn on 15 Nov 2017

I don't think they do Christmas Day, but some did Christmas eve last year. But currently only the La PArguera biobay is open. The Fajardo and Vieques ones are closed. We will have to wait and see if they reopen soon.

Comment by Gwenn on 15 Nov 2017

The biobays are not open for tours yet. The Dept of Natural resources is keeping it closed for a while.

Comment by Gwenn on 15 Nov 2017

Hi, we’re traveling to San Juan nov 22-25. Which bio bay would you recommend, that has been least affected by the hurricane? Will the glow be visible at all? If so, which night is best and Can I book the tour through your website, if I also need transportation from San Juan? Thank you!

Comment by Gloria Cannon on 12 Nov 2017

Do you know if Bio Bay tours are operated on Christmas Day?

Comment by Iris Galvez on 07 Sep 2017

We will be in PR from October 1-7. We really wanted to do the Bio Bay but the calendar is showing the whole time that we are there to be bad nights for it. Is it absolutely not worth it to go while we are there?

Comment by Keelin Darby on 02 Sep 2017

It would be too far a drive to get to Fajardo from Rincon. Definately do La Parguera. It is inexpensive, and you might get a good glowing night.

Comment by Gwenn on 30 Aug 2017

Thank you for the calenders!. I have a short trip planned 10/18 thru 10/21/17. But we will be staying on the west end of island in rincon. Ive read negative reviews of the 3rd bay at parguera. Should we make the drive to the second option or chance it since they're good nights moon wise?

Comment by Jackie on 28 Aug 2017

I have only heard the companies doing the tarps in Fajardo. That is not to say no one in Vieques does it, but I don't know of any. You may have to call a few and ask. A number of companies just don't go out during "bad" moon nights. However, some have different ideas of what makes a night "bad" or "fair" or "good" than I do. This calendar is just my opinion.

Comment by Gwenn on 29 Jul 2017

Does anyone personally know a tour company/companies that offer tarps etc mentioned in the article to help block out the moon in the event you have no option but to go out during full moon or less than ideal days ? I will be in Vieques September 7th & 8th 2017. Any help locating a tour company to suit our needs helps. Gracias!

Comment by Janis on 25 Jul 2017

I like the earlier tour, just so you can sort of see the channel and other boats. It will be dark by the time you are in the lagoon. In summer I think they change the tour time a little later, just to make sure it is dark enough when you reach the bay. But really, any time that works best for you and your dinner or driving plans will be fine.

Comment by Gwenn on 21 Jul 2017

Oh my goodness first off, thank you for posting this, makes it much easier. Secondly I am arriving P.R. Aug 10 @ 4pm, wanting to do the Fajardo kayak Bio-Bay tour. There are two times 5.30-7.30pm and 7.30-9.30pm. Which would be best as far as seeing the bio and enjoying the view of the bay? seems like it starts with check in, safety lesson, and then we hit the bay. Sun sets at 7pm that day. Thank you so much again

Comment by dee on 12 Jul 2017

yes, it is term used to describe the is when the moon is not visible. So it is a great time to go and see the biobay

Comment by Gwenn on 11 Jul 2017

what does "new moon" mean? Is that a good night to go out?

Comment by Erica Crowder on 11 Jul 2017

Hi- the moon on the 23 is best also...just hard to get best lines and new moon dots together. Any time on either of those days is great, similar viewing. So pick which time works best for you for dinner or other activities.

Comment by Gwenn on 10 Jul 2017

Hi, We are looking to book either the 6:30 time on 7/22 for bio bay kayak or the 8:30 on 7/23. (or we could do the 6:30 on 7/23.) Which is best? I was surprised by your calendar that the new moon (on 7/23) was good, but not best? Curious why.

Comment by Leigh on 10 Jul 2017

Well, it is all my opinion....June 30th the moon is at 50% brightness and is directly overhead at 6:30 or so. July 1st, it is at 60% brightness and is overhead at 7 or the 30th is better. Possibly the second tour on either day would be better, but the 30th will be better than the 1st. Neither night wil be horrible- you will see the sparkle. Either way, you are late in booking...see what is available.

Comment by Gwenn on 15 Jun 2017

We are visiting Puerto Rico and were considering doing the Bio Bay electric boat tour in Laguna Grande. June 30th says 'Good' and July 1st says 'Fair'. Is there a big difference between the two in terms of viewing? Also which time do you recommend, the earlier or later time?

Comment by Paula N on 14 Jun 2017

either time will be great viewing.

Comment by Gwenn on 24 May 2017

Yes, it is worthwhile. Either time is good.

Comment by Gwenn on 24 May 2017

will be there 12/24/17-12/31/17. can only reasonably do 12/25 Is a day labelled "Good" a worthwhile experience for Vieques? Is an early or late show better?

Comment by Tom T on 24 May 2017

Going mid July - early 6pm tour or the 8pm tour the best?

Comment by Lynn Davis on 24 May 2017 is not a great time..the moon is bright and almost directly overhead during tour times. Many companies will use tarps overhead to help block the moon light, and you can hope for clouds. You will see something, but it won't be great. You would have to decide if you think it would be worth it. Pick a company and ask them what they do for bright moon nights.

Comment by Gwenn on 22 Apr 2017

We arrive PR on 7/4-9 .. your calendar shows red .. should we even try to book a biobay tour?

Comment by kgnsam on 20 Apr 2017

The earlier date you can get would be better and the early tour.

Comment by Gwenn on 08 Apr 2017

The earliest date the better and yes, the earlier tour is better.

Comment by Gwenn on 08 Apr 2017

We will be in PR June 4-9, which is all red on your calendar. With he full moon being 6/9, would it be worth it to kayak the bio bay in Fajardo maybe Monday, 6/5? Would either the earlier or later time be better?

Comment by Erin on 30 Mar 2017

Hi, So bummed just realized our trip Nov 28-Dec 3 2017 falls when the moon will be bright. Can you advise which end of our vacation would optimize the darkness? Also earlier or later tour make a difference? Thanks!

Comment by Regina James on 30 Mar 2017

Last I heard it was at about 50% usual, which isn't great. It is quite expensive to do the Vieques one from San would have to decide if it is worth it to you. Just as an FYI- that is "spring break" here, so everything will be busy/booked up, so make reservations asap.

Comment by Gwenn on 29 Mar 2017

we will be in San Juan from 4/11/17 to 4/16/17, and the easiest spot for us to get to is Fajardo. Is the bay there glowing any brighter than it was in January and February, or would we be better off to go to Vieques?

Comment by Jody M on 27 Mar 2017

It is a great time- moon is up late. However the bay is not glowing as bright as it should, so maybe that is what they are referring to. Call a company directly and ask them.

Comment by Gwenn on 16 Mar 2017

ArrivIng tonight in San Juan, March 15 and leaving Sunday night, March 19. I would like to go to a bio luminescent tourist spot. Is this a good time and if so which tour would you recommend. The hotel I'm in keeps saying it's not a good time. But your chart says it's good. Please help.

Comment by Dawnmarie DeMatteo on 15 Mar 2017

nope- both perfect viewing!

Comment by Gwenn on 03 Mar 2017

Will be in Vieques 4-25 & 26. Does it make any difference if we take the 7pm or 9pm tour?

Comment by cherie on 02 Mar 2017

It is getting a little better, but still not great.

Comment by Gwenn on 24 Feb 2017

We'll be visiting March 8-15, and are thinking about kayaking the Fajardo Bay on Mar 14. Has the brightness improved in Fajardo yet, or is it still diminished? I'm hesitant if the bay is marginal and the light conditions aren't great either.

Comment by Eric Gr on 24 Feb 2017

The Fajardo Biobay isn't glowing well right now, so going over to Vieques to see their biobay is the only good choice.

Comment by Gwenn on 26 Jan 2017

Will be arriving in a few days on the 29th. We did the electric boat (I think it was) in the past where the mangroves are, very cool but glow wasn't huge. We'd like to see BioBay again but I'd like to know which is the best place to do the BioBay experience, especially with our timeframe considered??? Thank you!

Comment by Shell on 26 Jan 2017

It will be bright at night these nights. I am going to say the early tour, and probably the 8 or 9th. But honestly, the Fajardo bay is not glowing very well right now. It really may not be worth it during the full moon.

Comment by Gwenn on 22 Jan 2017

As the calendar says, all those nights are great. The time depends on what your plans you want to eat before or after the tour?

Comment by Gwenn on 22 Jan 2017

It will be a great night for viewing. But the bay is not really bright right now. Contact the company you want to go with and ask them exactly how it is. They should tell you. People still will see sparkles, but it is not as amazing as it should be.

Comment by Gwenn on 22 Jan 2017

Hi - We'll be in PR from Feb 7-11 and it looks like it might not be the best time for bio bay. We really want to do it however - out of the days we will be there, which date would you recommend based on your experience? Thanks!

Comment by Sam Mish on 16 Jan 2017

We will be in San Juan on January 31, and would appreciate your input on the the bio-bay trip at Laguna Grande at this time, thank you.

Comment by Laura on 07 Jan 2017

Hi we will be staying at the El Conquistador Feb 19 to 24th. Which night would be the best to kayak Bio Bay and it it better to do the 6:30 or 8:30 trip? Thanks!

Comment by Kathie Kobi on 07 Jan 2017

according to the calendar....any date after the 15th

Comment by Gwenn on 12 Dec 2016

Which date is best on December in 2016?

Comment by stacy on 06 Dec 2016

We have a tab on the site for traveling with kids: But they could be into horses, go-carts, hiking, beaches, history and Old San Juan, some adventure tours, snorkeling. But mostly, from my experience, beaches!

Comment by Gwenn on 12 Nov 2016

We are visiting SJ PR for the very first time in January? I have two children ages 10 and 7. I would like to spend some time sight seeing and enjoying. What are some recommendations for children in their age range?

Comment by Annie B on 10 Nov 2016

My opinion is the calendar (I made it!)- the 17th or 18th will be great viewing.

Comment by Gwenn on 09 Nov 2016

I'll be visiting Vieques November 14-19, 2016. I'm hoping to visit Biobay again by kayak at night. With the super moon, I am not sure what night would be best. Any ideas? The last time we visited, there was a full moon and the kayak tour was almost canceled. They said a full moon makes it so that you can't see the luminescence of the bay. Any comments?

Comment by Susan J on 09 Nov 2016

According to the calendar, the 19th would be the best night (either time), but the early tour only on the 18th would also be good.

Comment by Gwenn on 09 Oct 2016

Hi. Will be in Fajardo (Oct 17-20) for 40th anniversary with family. Which nights & times do you suggest bio tour? Thank you! Mary ????

Comment by Mary on 08 Oct 2016

You could keep your fingers crossed for a cloudy/rainy night.

Comment by Ray on 05 Oct 2016

I'll be in Puerto Rico from the 8th December - 14th December. :( Oh... me and my back luck. I am planning the activities, guess it's better not to book the tour for the luminescent bay, then (?) Thank you for this website, by the way.

Comment by Jaime Oliveira on 05 Oct 2016

I would try to go on the would be better. The 8th won't be good. If you rent a car, yes, I think you can get to the second tour. I am not sure if the tours make a second pick up at OSJ Hotels. That you would have to call them and see.

Comment by Gwenn on 30 Sep 2016

yes, those nights are good. Actually, the earlier tours will be darkest...the bright moon rises 9pm on the 16th.

Comment by Gwenn on 30 Sep 2016

Hi Gwenn, will Dec 16 and 17 be okay in Vieques? I know it is only 2-3 days after full moon, and not sure if it is worth it to go to Vieques at all. And if it is okay, the later the trip the better, correct?

Comment by Bert on 29 Sep 2016

We will arriving in San Juan on Jan 1, 2017 to leave on a cruise on the 2nd and arriving back in San Juan from the cruise on the 8th. According to the calendar, the 1st appears to be the better of the 2 days to see the bio bay. Our flight doesn't arrive in San Juan until 4pm(depends on delays) on the 1st. Is there enough time to check into hotel in Old San Juan and still go on a tour? Or would it be better to wait until Jan 8th? Or do any of the tours pick you up at the airport? Thanks

Comment by Kari Van Eps on 14 Sep 2016

The Aquarius is in Dorado I believe....about 2 hrs from Fajardo. That is a long drive to see the bay. I don't know if any tours go from there to would have to check with the hotel.

Comment by Gwenn on 06 Sep 2016

My friends and I will be going to Puerto Rico from October 21-24th. Planning on doing this Sunday the 23rd(October) we will not be able to stay over night in Vieques so we are opting for Fajardo. Any recommendations? We are staying at the Aquarius Vacation Club Resort. So the hotel would be able to book us with best tour group?

Comment by Eileen on 06 Sep 2016

Well, it depends on where you are staying. The one on Vieques is the best, but it requires an overnight on Vieques. Fajardo is the next best and is about a 1 hr drive from SJ. If you are coming back to PR, then yes, it might be best to wait.

Comment by Gwenn on 28 Aug 2016

I will be i puerto rico from oct 9th till the 13th. I saw on the calendar that those are not great days to visit the lake. which lake would you recommend? Or would i better visit the lake on my next trip?

Comment by sus on 28 Aug 2016

Getting out on the water in a boat will always give a better view of the glow. And, they have the option of going to different parts of the biobay to search out the glow.

Comment by Ray on 08 Aug 2016

Hello! We are planning to visit Laguna Grande on August 11. It's a fair day. Our options are the walk tour or the electric boat as we have a 4 year old with us. Which do you think will give us a better experience? Thank you in advance for your advice and thanks for your amazing web-page loaded with info. Mme. Groussolles

Comment by Mme. Groussolles on 07 Aug 2016

yes, the moon will be good for viewing the bay. Last I heard last month, Fajardo biobay was at about 60% of normal, I am hoping our hot sunny summer days are helping it improve more.

Comment by Gwenn on 06 Aug 2016

We will be visiting Puerto Rico on August 22, 2016. Will that be a good night to see the bioluminescent bay at Farjado? At what percent is it glowing?

Comment by Kim on 29 Jul 2016

yes, the moon is very bright and it is just after the full moon BUT- it does not rise until 9:45pm. I would do the first tour, but either tour should be great.

Comment by Gwenn on 20 Jul 2016

I am planning on seeing mosquito bay September 20th. Your chart says it is one of the best days, but the moon phase calendar shows that the moon is over 50% full. Are we safe going with the latest tour or should we go early?

Comment by Nicole Rawski on 19 Jul 2016

Yes. According to what we calculated for the calendar, that would not be a good time to go to the biobay.

Comment by Ray on 17 Jun 2016

So this would be a bad week to go 6/12 to 6/18?

Comment by al on 12 Jun 2016

Well, if you really want to experience the glow, you should go to Vieques. But call operators to make sure they are going out (some will not go when the moon is bright). Plan to go early on in your stay as the closer to the full moon you visit, the worse viewing will be. I would not spend the money for Fajardo with your dates.

Comment by Gwenn on 02 Jun 2016

Bueno ~ I am returning to the island for a visit with my husband and 4 children (ages 7-19) for the first time in 12 years. My kids have either little memory or have not traveled to PR. We will be staying near Fajardo and I would like to take them through a bio bay. In your opinion, should I spend the money for a hotel and travel to Vieques or will the kids enjoy the experience at Laguna Grande? We will be there June 11th-18th. !Muchas gracias!

Comment by Inés on 01 Jun 2016

Last I heard (about 2 weeks ago), Fajardo was still only at abut 20% usual light. Vieques is at 100% normal glow.

Comment by Gwenn on 06 May 2016

Hello, Can you tell me what the current conditions in Fajardo and Vieques are? Assuming a visit with no moon, what % are they currently glowing at? Thanks!

Comment by Jordyn S on 05 May 2016

Hi, I just came back from San Juan yesterday, loved it! Just an FYI, I was told that from the tour desk at the hotel(Marriott Stellaris) that the Bio Bay is only at 10% right now. They will however, still book tours.(I made the decision to pass on this).

Comment by Carol-Ann on 05 Apr 2016

You can wait and see when you get here what night works for you. And how the bay is improving.

Comment by Gwenn on 23 Mar 2016

Hello, Another question I forgot to ask. Do you recommend booking ahead of time? I was planning on booking through my hotel when I arrive. Thanks!

Comment by Carol-Ann on 23 Mar 2016

Fajardo will be better than Parguera. It is already and is improving every day. October can be wet, so that can reduce some of the "glow", but generally a good time for viewing. But yes, that is low season here, so you can wait until a few weeks beforehand to double check and book.

Comment by Gwenn on 22 Mar 2016

Our Trip is planend in two options: October 19 th in Parguera Oktober 21th in Fajardo Is it possible to say, which one is better? Is October a good month for viewing in General? Should I wait to book until a short Time before to see how the situation is?

Comment by Sandra on 22 Mar 2016

The bay is improving, but it is still not anyway near peak brightness. Any of those nights are great for little moon. Early or later would be either time that works best for you...some people like to see the mangroves on the way in, others want total darkness. Sunday has only 1 kayak company that goes out, so that is nice (less "traffic" in the channel).

Comment by Gwenn on 21 Mar 2016

My trip dates are 3/31-4/4. Planning on the Bio Bay in Fajardo. Do you think conditions will improve? Also do you recommend the early trip or the later one? Thanks. I love this site!

Comment by Carol-Ann on 21 Mar 2016

Well, it sky will be bright and the bay isn't glowing well. It is pretty pricey just for a night kayak.... I don't know if I would do it. Mosquitoes can be a problem, but the company should provide eco bug repellent.

Comment by Gwenn on 14 Mar 2016

Our trip is booked for 5 nights, March 20-25. Full moon is Wed 3/23. Our concierge booked us on the Thurs night 6:30 bio bay kayaking trip for my 12-year-old son, my husband and me. After reading this, thinking of cancelling. An evening paddle in the Caribbean through mangroves at the edge of a rain forest has its own alure, with or without biolum, but its pricey without that unique feature. Thoughts? And, how bad are the mosquitoes at night on these trips?

Comment by Carol on 14 Mar 2016

I don't think it will be much improved by has been a bit rainy lately, not too much sun. But you can try contacting the tour people directly and they will probably have a better idea.

Comment by Gwenn on 06 Mar 2016

Any idea what the bio bay in Fajardo will be like March 25-31? I know it's supposed to improve as the weather warms. You're site has been extremely helpful as we plan our trip. Thanks!

Comment by Catherine Allen on 04 Mar 2016

Any night is equally good, but yes the bay is not glowing as bright as it should. Is it worth Is it worth $50pp- no. But if there is a discounted rate, then yes, probably could be fun.

Comment by Gwenn on 26 Feb 2016

The best days would be the 13 and 14th. The moon will be more overhead on the 13th and just almost overhead but a bit brighter on the 14th for the first trip. There are 2 companies that do electric boats, but the rest are kayaks.

Comment by Gwenn on 26 Feb 2016

Hi Gwenn, My family and I will be in Puerto Rico this week. We will be there from 2/29 - 3/4. We are looking to do the Bioluminescent Bay in Fajardo. I have been reading reviews and feedback from others that it hasn't been so great lately. Do you think it is still worth the trip to see it? and if so, which of those days would you say is best? ( We do not have the time to go to Vieques unfortunately.)

Comment by Jon N on 26 Feb 2016

We will be in PR May 13-15, which is best day to visit for Fajardo? Do all the companies take the kayak up the channel and should I go later or earlier (I know it says fair, but just curious about moonrise/set)

Comment by Ed Z on 26 Feb 2016

The Vieques Biobay is glowing normally for this time of year. Very well. The Fajardo Biobay is glowing at about 50% for this time of year. But to see the Vieques bay, you need to get there and then spend the night.

Comment by Gwenn on 12 Feb 2016

Is there any objective way to determine how luminescent Mosquito Bay will be on March 14? My family and I are going to be staying in Fajardo and are weighing the pros and cons of just flying to Vieques and seeing the bio bay there instead. The reviews seem like night and day between Vieques and Fajardo.

Comment by David L on 12 Feb 2016

If you are talking about 2016, the full moon is on the 23rd. The 15 and 16 or 17th are the best nights for you, always early tour. The moon won't be very bright, but it will be directly overhead.

Comment by Gwenn on 11 Feb 2016

We are planing a trip on march 15-20. And I checked that the full moon would be on the 25th. Which date would you recommend us for the tour? either earlier or latter period of the night? Thanks!

Comment by Liz Lu on 11 Feb 2016

You can check with the tour companies on Vieques. Some of them will go out these nights and find a darker corner of the bay. Best bet would be earliest tour possible on the 19th.

Comment by Gwenn on 10 Feb 2016

My husband and two teenagers will be staying on Vieques Mar 19th - 22nd. I'm so disappointed to see all of those days marked "bad". Do you recommend any one of those days as better than the others? Should we skip it altogether?

Comment by Jolene Houston on 10 Feb 2016

I think the 7:15 trip would be fine....the moon will be bright but still not yet on the horizon during that trip. If the company does a 6pm trip then it should be dark enough during the trip I would think. So that one should be ok too.

Comment by Gwenn on 09 Feb 2016

Thank you for such a great site. Looking at August 20, which is Good Early/Fair later. Would the 6 PM tour be too early? Sunset is 6:48 that day. I wasn't sure if the 7:15 trip would be too late (regarding the "Fair" later). It looks like moonrise is around 8:40 PM that night, so perhaps 7:15 is the best bet for that night? Trying to figure out if the sun not setting until almost 50 minutes into the 6 PM trip outweighs the "good early". Any thoughts would be appreciated. Thanks!

Comment by Lola V on 09 Feb 2016

Yes, the first tour on the 25th, then the first tour on the 19th would be my first choices, then the first tour on 20th.

Comment by Gwenn on 09 Feb 2016

We will be in Puerto Rico 3/19-3/26 and I see the moon calendar is not very favorable BUT we still want to book a tour. In reading previous comments I see an early eve tour seems to be the most recommended....any recommendation on a specific date or dates?

Comment by Katie W on 09 Feb 2016

The earlier the better.

Comment by Gwenn on 05 Feb 2016

HI, we are planning to visit bio bay on March 19th, but the calendar said it will be a bad timing. Should we go in the early evening or after 8:15 pm? thanks!!!!

Comment by chenxi xu on 05 Feb 2016

You can check flights from Isla Grande airport (a 10 mins taxi ride from SJ airport). You can go directly from there to Vieques. Otherwise you will need to get to Ceiba, which is a 1-1.5 hr drive from SJ. Check flight times, from both places and rates. Sometimes it is cheaper to rent a car and drive yourself to Ceiba, and park the car overnight.

Comment by Gwenn on 30 Jan 2016

Hi Gwenn, Thanks a lot for your reply. I read a lot of comment and it is very helpful. I am planning to visit Vieques and spend a night over there. I check there are a airport call Ceiba. How can I get to this airport. I am fly from the United States. So the first place I arrive will be San Juan. Should I choose to stay near the airport and the next day fly from San Juan to Vieques or take a taxi to Ceiba? Thanks

Comment by Enyun on 29 Jan 2016

I would try for the 13 or 14th. The moon will be getting brighter every night and it will be more overhead after the 14th.

Comment by Gwenn on 29 Jan 2016

Hi, I want to visit PR in March. I saw the calendar indicated that 13-14 is good. Well, 15-16 is fair. I am planning to go to Vieques to see the BioBay. Which will be the best day to see BayBio? Thnaks

Comment by Enyun on 29 Jan 2016

Beside the bay not glowing well now, no you will probably not have enough time to safely be sure you will be back to the ship on time. The first trip only finishes at about 8:30, and then the hour drive back. Barring traffic and other issues. I guess it is possible, but probably not worth the worry (especially since it is not great viewing anyway.

Comment by Gwenn on 26 Jan 2016

The best way is to fly/ If you have a car rental, drive to Ceiba airport and fly from there. The ferry is an option, but it isn't always fun/reliable. But call and make sure you can get a tour in Vieques....some companies don;t operate during full moon periods.

Comment by Gwenn on 26 Jan 2016

Great site! I will be there Feb. 18-24 all "bad". Staying in Fajarado but understand that the aby there isnt glowing well. I would be willing to do an overnight trip to Vieques but my question is what is the best way to get to Vieques from Fajarado?

Comment by Jason T on 25 Jan 2016

Hi Gwenn, We will be in San Juan on 2.16. 2016 via cruise ship. Thinking about viewing the rain forest and then trying to make it to one of the bay's. Moon does not look good for that day... Should we attempt anyway, which location, will we have enough time to make it back to port by 10:00 PM, Kayak, Boat or Walking Tour, can you advise which company to use? Sorry for all the questions, your advice is greatly appreciated!

Comment by Chardon on 25 Jan 2016

That does sound a bit early for March. Sunset is 6:35pm. I assume they don't start at 6..probably have a safety thing and then getting you in boat etc...may take a little time. You will be able to see the mangroves as you go through them (which is nice). It will be dark dark by 7. They probably go to a dark corner of the bay. I guess they know what they are doing.

Comment by Gwenn on 24 Jan 2016

We are going on march 12 but its at from 6-7:15 pm. Im worried that there will be to much sunlight to enjoy this... Is that right?

Comment by Robin on 24 Jan 2016

The only way to see the Vieques Mosquito Bay is to stay the night on Vieques (the catamaran trip isn't running now). Look for a place in will be limited in your choices since it is only 1 night. There are a number of kayak companies that do the tour over there.

Comment by Gwenn on 19 Jan 2016

Hi Gwenn, we have a trip booked to stay in San Juan in March. We have already booked our hotel and really wanted to go to mosquito bay especially because we will be going in the beginning of the month when the moon is the best. We really wanted to do the kayak tour but I realized that the ferry back to fajardo is 6:30pm. I don't know when most of the tours are but I'm assuming that we would get stuck on the island. I saw the catamaran option but my boyfriend get sea sick easy and we both love kayaking (for whatever reason that doesn't bother him) Do you have any suggestions on how we should go about planning this? Is my only option to get a hotel their for 1 night and see if I can get my money back for 1 night of my hotel in San Juan? If so do you have any good suggestions of a nice clean affordable place on the islands? Thanks!

Comment by Thais on 19 Jan 2016

The earlier in that week and the earlier trip would be better. 16th or 17th early would be your best option.

Comment by Gwenn on 16 Jan 2016

Hi Gwenn, me and my fiance will be visiting PR for our honeymoon on the 5/16-5/22 and it is on a bad week sadly. She is very excited about this so she wants to go either way. Is there a day where you consider the best day to go out of that week or maybe a best time slot on that day? or what do you recommend? Ivan

Comment by Aurelio Ivan Ruiz on 15 Jan 2016

The first tour on the 20th...the moon doesn't rise until 7:41p,. but it will be bright. They will probably be able to get you to a dark tree covered area to view the water.

Comment by Gwenn on 13 Jan 2016

Gwenn, I've review all the comments and this is pretty interesting-thank you. I plan to visit PR and stay in Fajardo July 18-21, 2016 and one of my plans was to do the BIOBay; but after review the moon calendar it's pretty disappointing. Just our luck, calendar says full moon those days. Do you recommend if we do decide to do the tour (if available) to do the early one? Idalia

Comment by Idalia Cazres on 13 Jan 2016

Maybe the first tour on the 20th or 21st. Moon will be bright but not overhead.

Comment by Gwenn on 11 Jan 2016

will be in condado 1/18-1/22 but per the calendar these are all bad nights to go. Any recommendations- would love to see this!

Comment by sara on 10 Jan 2016

The Vieques biobay is glowing as usual- very bright. Fajardo biobay is improving but still might not be great by early March. Both nights you mentioned are perfect for viewing. Vieques has some beautiful beaches, it is worth the effort to go. Find a room for the night and enjoy Vieques.

Comment by Gwenn on 07 Jan 2016

I'm visiting in March and we're planning either a visit to Fajardo on the night of March 11th, or making the trip to Vieques for a night on March 13th (slightly more moon illumination). Which day would be better? Are the conditions in Vieques bay better than Fajardo?

Comment by Christine on 06 Jan 2016

Yes, Fajardo is not glowing well- the organisms took a bad hit this fall when a huge mass of seaweed came into the bay. As it died, it took all the oxygen out of the water. The organisms are slowing making a come back- but being "winter", the colder weather and the shorter days give less sun and warmth they need to thrive. People are still going out for the tours and some are happy and some are disappointed. You need to set your expectations correctly.

Comment by Gwenn on 30 Dec 2015

Interesting read of all your reviews and comments. You run a great site! I'll be heading to PR next week (jan 3-11) with a biobay stop sometime mid week. Calendar looks great, but I see several comments regarding 'bad times' in Fajardo. Why is this? Is this the only bay with 'bad glows' right now? Was originally planning to early evening cruise out on the 5th.

Comment by Paul Belobraydic on 30 Dec 2015

According to the moon calendar, it is a good time for viewing a biobay. Just realize right now the Fajardo biobay is not glowing well.

Comment by Gwenn on 27 Dec 2015

Thinking of heading there on vacation between Jan 11-14, would go 12-13, 2016. Would this be a good time to go?

Comment by Bianca Colon on 27 Dec 2015

Yes, the 8th will be perfect viewing moon-wise. Island Adventures ( has a nice electric pontoon boat that will work perfectly for your group. Just realize, the bus ride to the bay is very bumpy, so that is a bit troubling for some older folks....

Comment by Gwenn on 27 Dec 2015

We are planning a trip to Vieques for the bio bay on June 8, 2016. Will this be a good night to go out? Also, are there any boat tours for the bio bay (not kayaking) on Vieques? My parents don't want to do the kayak tour, so we are looking for a tour for them.

Comment by Jessica on 27 Dec 2015

Well, the sky will be bright, just due to the moon. I think your best bet would be - 1st choice-25th, then maybe the 24th, then the 21st. The earlier trip would be better no matter what night you choose.

Comment by Gwenn on 27 Dec 2015

They have both kayak tours and electric boat tours. Since you are no longer allowed to swim and go in the water, I think kayaking getting you closer to the water, so you can splash around with your hand, feet and oars.

Comment by Gwenn on 27 Dec 2015

Hi, We are planning to going to vieques bio bay on 16th January. The moon calendar says Fair. Do they have kayak tours there ? Or is it advisable to do the electric boat tour?

Comment by Ishu Gupta on 27 Dec 2015

We will be in PR from March 21-March 25, all of which are on or around a full moon. Which night would be our best bet to see something glow? And which tour--early or late? Thanks!

Comment by Christine on 26 Dec 2015

Well, the bay is not glowing too well right now, so the glow will be even less visible during a bright sky. I love doing the electric boat, but with the walking tour you learn and see other things too....

Comment by Gwenn on 19 Dec 2015

Well, it is after a full moon, but it will be rising later in the evening, so the first tour will have less moonlight, but still some. And the bay isn't glowing too well right now. So adding thoe things won't be great viewing. Some people see the sparkles and are happy, others aren't impressed.

Comment by Gwenn on 19 Dec 2015

Gwenn, our only options (at the end of January) are Full Moon and Fair Early/Bad Later nights by electric boat. We will be in Farjardo staying at the El Conquistador right next to the bay so it seems like it'd be a shame to miss it. Would the walking tour be a better call? I'm pregnant so the kayaks are not an option, unfortunately.

Comment by Rachel on 18 Dec 2015

Viewing should be great if there is anything to see. You may get lucky and maybe the organisms will be cooperative (all depends on weather and sea conditions etc). Some of the companies offer a reduced rate because it hasn't been too good lately.

Comment by Gwenn on 18 Dec 2015

I hear it is still not too bright.

Comment by Gwenn on 18 Dec 2015

Hello, my husband and I are honeymooning in Puerto Rico and plan to do Bio Bay on 12/27/2015 at 6:30pm from Fajardo. Is this a bad day to go? Should we not go at all? The calendar says Fair Early, Bad Later.

Comment by RP on 16 Dec 2015

Hi we booked a Fajardo bay kayak tour on Dec 29. Will it be a good day to go? Will it be worth going considering the current so called "bad" condition?

Comment by Ethan on 09 Dec 2015

How is the Biobay in Fajardo ? we will visit from Dec 14th - 19th

Comment by crystal on 07 Dec 2015

Any time tour will be great! There will be no moon to dilute the darkness.

Comment by Gwenn on 05 Dec 2015

We will be in Vieques on the new moon January 9, 2016. Can you recommend a better time early or late? We are staying on the island and it is a new moon. Thank you

Comment by Gary on 04 Dec 2015

The company is wrong. Full moon is Dec 25th. You have to be in the dark to see the glow. You are wearing a lifevest, so the no swimming is not an issue. Which bay? If it is Fajardo, unless something improves, I would probably not go. In Vieques, I would try it. On the 26th, the moon rises at 7:21pm, so the first tour may be ok.

Comment by Gwenn on 02 Dec 2015

Hi Guys , I am going to biobay on 26th Dec 2015 . The company said the full moon is on 27th Dec but the calendars say its 25th. All the places are booked and I want to go during the earlier tour because i am scared of the dark and both me and my husband do not know swimming. Do you think its worth going ? I hate to miss this experience. If the moon rises late on 26th then it would be ok but I am not sure now. Please give any thoughts, suggestions. Thanks

Comment by Aparna on 02 Dec 2015

You may need to call ahead to make sure the companies are still going out. I think a few don't go during a full moon (or at least they used to not go). You will see some, but the bright sky makes it hard to see the organisms, but the tours will try to take you to the darker areas of the bay. And if there are clouds, you will be able to see more. I would recommend the first tours on the 20th or 21st if you can get them.

Comment by Gwenn on 01 Dec 2015

Hi we're going to be on Vieques from 12/20 to 12/25. Which, of course, is right before the full moon. Is it worth a shot to book ahead, and if so which company would you recommend? We'll be staying in Esperanza. And is 'bad viewing" = see nothing, or just not as luminous. Thanks.

Comment by Clara Jeffery on 29 Nov 2015

Well, hopefully the bay improves, but right now, it is really bad. We have done tours with Kayaking Puerto Rico, and really liked them. Call them and ask about their cancellation policy- They will tell you the truth about how the bay is doing as your trip gets closer.

Comment by Gwenn on 25 Nov 2015

Sadly, I would cancel the trip. The bay is really bad right now. Stay in Old San Juan and enjoy the Christmas lights!

Comment by Gwenn on 25 Nov 2015

The Fajardo bay is really bad right now. I would skip it. There is no way to see the Vieques Biobay without spending the night.

Comment by Gwenn on 25 Nov 2015

I believe there will still be tour companies taking people out, even though it may be bad viewing. If they have room, I am sure they will gladly take you out.

Comment by Gwenn on 25 Nov 2015

Hi We are spending xmas in Vieques (23rd to 26th of December). According to the calendar that is a really bad time to visit the biobay. If it happens to be a overcast evening it might be worthwhile - but are there any tours around xmas time and secondly can we join a tour a such short notice?

Comment by Robert Svanberg on 25 Nov 2015

The Fajardo bay is still bad...really bad.

Comment by Gwenn on 24 Nov 2015

Hi, We booked the 5:15pm tour with a kayaking company at Fajardo bio bay for Saturday, November 28th. I just found out about the condition at Fajardo and I am very concerned. I really really want to see the bio bay. What would you advise? What are our chances of seeing the bioluminescence? Is Vieques going to be a better option? Is it possible to do without staying overnight? Thanks in advance!!

Comment by Madhura Mukherjee on 23 Nov 2015

How are the current conditions of the biobay in Fajardo? We will be visiting the end of December and I have read in some blogs that conditions have been improving due to recent rainfall.

Comment by selma on 23 Nov 2015

Hey There! have booked thru our cruise line for Dec 8th 2015. Looks like a good "moon phase" day - but am reading that Fajardo is not currently glowing well (not so healthy?) SHould we rethink this as not worth the time this trip?

Comment by Betsy B on 21 Nov 2015

Hi- With all the recent rain I have heard that conditions in the bio bay in fajarto have improved a bit; that it may be "worth it" to take an evening tour. We will be in the area the end of December and according to your calendar those are good nights. However, do you think conditions have/will have improved enough to see a bit of luminescence? Also, do you recommend all of the companies that have tabs/banners along the right side of your webpage? thanks

Comment by selma burn on 20 Nov 2015

At this time, due to the weather, the glow issues and how far you will be coming, I really don't think it will be worth it for you. But if you are really into it, only 1 kayak company goes out on Sunday- The Kayak Company.

Comment by Gwenn on 20 Nov 2015

You will have to stay the night on Vieques if you want to go to Vieques biobay. Sky will be bright and directly overhead those days, but a tarp might help. But the Fajardo biobay is having some health issues now due to seaweed, so if you really want to go, check out Vieques.

Comment by Gwenn on 20 Nov 2015

The earliest day you can gt and the early tour. The moon is at the 1/4 and getting bigger every day and it is overhead. Vieques bay is the best, but you would have to plan an overnight there to see it.

Comment by Gwenn on 20 Nov 2015

Hi there. We will be in PR April 15-22, 2016. We're hoping to do a bioluminescent tour, but that looks like the worse week possible. Is there any day/time in that week that would be better than another? Would 1 location be better than another? Should we just skip it?

Comment by Kim High on 18 Nov 2015

I think i Need some help. We plan to go at 2105 Dec20 to Dec 24, according to the calendar provide. those are all bad days. Should we bother visit? would the Biobay at Viequs better? or the biobay at Fajardo (heard that the tree can block some light) ? Thank you very much.

Comment by Andy Wang on 15 Nov 2015

Hi, We will be in PR from the 27th November until the afternoon of 1st December. According to the calendar, 30th November, Monday is the best day to see the biobay. Two questions, one, we will be in Dorado, which bay would be the easiest to get to and also the best for viewing--the thread above mentions Fajardo not glowing well right now? And is it safe to book a tour in advance for the 30th which will be the last day of the trip? I mean since it is the last day, if the bay doesn't glow we aren't really left with another day to do it again. Thank you! This discussion thread is fantastic!

Comment by Nams on 13 Nov 2015

If you are talking about going to the Viequs biobay on Dec 27, if you can get to the earlier tour, it should be ok. For the Fajardo biobay - unless it really perks up, I wouldn't go the 27th.

Comment by Gwenn on 11 Nov 2015

As the calendar indicates, they are not good for viewing. And the Fajardo bay is not glowing well right now won't be worth the money or effort to go those dates.

Comment by Gwenn on 11 Nov 2015

Hi, We are planning a trip to stay in Puertorico prior to our cuise. Dates of stay are Nov 20th & 21st and boarding ship on 22nd. Can you tell us if those two nights are good for biobay tours?

Comment by Kevin on 10 Nov 2015

According to our calendar any of those nights are great.

Comment by Gwenn on 08 Nov 2015

I'm thinking going on a biobay tour on Dec 27 or Dec 28. Since I have a really tight schedule and not sure if I could get the ferry to Vieques... So might considering gong on 27th. Would 27th be very bad and much worse than 28th?

Comment by Ziqian Li on 04 Nov 2015

I'm in PR now, and someone told us it will not be good to go until the 8 th of November and we will be leaving. Is the 5 the or 6 the of November any good?

Comment by Sheryl Croce on 04 Nov 2015

Any and all those dates and times will have great viewing. Pick which date and time works best for your schedule.

Comment by Gwenn on 02 Nov 2015

We will be in the Fajardo area March 28 to April 1, Easter week. What would be the best day to go? Early or late?

Comment by Carolyn Mitchell on 01 Nov 2015

Well, if I had my choice, I would do a tour on the 1st. But really any day would be the earlier tour on the first 2 days if those are the days you choose.

Comment by Gwenn on 16 Oct 2015

That is the best time to see the glow- when it is totally dark.

Comment by Gwenn on 16 Oct 2015

Hi! We'll be visiting San Juan Oct 29-Nov 2. Which trip do you think is best, and when? Would we need to provide our own transport to Vieques? Thanks

Comment by Scott daniels on 16 Oct 2015

We are planning on 12-11-15, when there is a new moon. Is this still a good time to see the glowing bay on the island?

Comment by Richelle Cain on 16 Oct 2015

Without Vieques as an option (which is the best), the second choice is Fajardo biobay. Currently it is having some issues, but it is still better than the one in Parguera. Any of the nights you are there are equally good.

Comment by Gwenn on 15 Oct 2015

Hello! My wife and I will be in Puerto Rico Dec 30-Jan2, 2016. I would like to experience the best Bio night and site, minus the Vieques site. Thanks in advance!

Comment by Juan Cuellar on 14 Oct 2015

Not having any moon certainly helps, but the days around the new moon are probably equally as good.

Comment by Gwenn on 12 Oct 2015

Out of all the days on the calendar would seeing the bay on the new moon day, be the best option?

Comment by Danielle on 12 Oct 2015

Currently you have to spend the night on Vieques to see their bay. So, if you can work that into your plans, that would work. If not, try for the first trip in Fajardo.

Comment by Gwenn on 10 Oct 2015

Either date (13 or 14) is equally good, though only a couple tour companies go out on Sundays. The first tour o the 15th would be ok too, but not as good as the other dates.

Comment by Gwenn on 10 Oct 2015

Well, the moon is near full those days. Your best bet would be first trip on the 27th. Currently the Fajardo biobay is not glowing fully, but that may change by November.

Comment by Gwenn on 10 Oct 2015

Hi, We are will be in Puerto Rico from 12/22-12/27. Our return flight is on 28th afternoon from San Juan. Bio-bay calendar shows all of the days as bad, and only 27th as "fair early/ bad later". Would you recommend the early trip on 27th in Fajardo? Or do you recommend early trip on 27th in Mosquito Bay?

Comment by Sree on 09 Oct 2015

I love your site and am so grateful for the calendars above! We are thinking we'll visit Puerto Rico from February 13 2016- February 21 2016, though based on the above calendars I wonder if we should choose a different week. Do you think if we book a visit to bio bay on the 13th or 14th of February, we'd have a good experience (and does it matter which of those dates we choose?). Based on the calendar, I am writing off the rest of that week as not worth trying... Thanks so much!

Comment by Eleanor on 05 Oct 2015

We will be in Puerto Rico with family Nov 24-28 2015 and wanted visit a healthy bio bay. On the calendar/chart provided all those dates are indicated to be bad. I wanted to ask you if there is any hope of a worthwhile bio bay experience or if we should just accept this truth and spend our time/resources doing something else? Perhaps, you have other ideas?

Comment by Shivali on 02 Oct 2015

I think all those nights will be pretty similar viewing. Get on the early trip, so the bright moon is not overhead.

Comment by Gwenn on 22 Sep 2015

Hi, I will be planning on being in Puerto Rico from 10/24-10/30. We want to do the bio bay tour in Vieques any night from the 25-28. That whole week doe s not look favorable, but which day would you recommend, and what time? The 29th looks like the only decent day but we would likely miss our flight on the 30 if we did it that night. :/ Thanks!

Comment by Humera on 20 Sep 2015

The first tour on the 28th will be ok, better than the 27th...bright moon but not high in the sky. The only way to see the Vieques BioBay is by staying overnight. Right now, no boats are running back and forth the same evening. Right now, the bay in Fajardo is so-so due to seaweed. But hopefully it will be cleared out by November.

Comment by Gwenn on 20 Sep 2015

Hi! We wil be in PR on 26, 27 and 28 Nov. From the calendar, 28th seems to be the only 'fair' day to go. What tour time would be recommended? Also, should we trying going also on the 27th? Is there any other tour company that could take us to Vieques in the evening and bring us back to Fajardo at night. Our flight leaves at 3 am on 29th Nov. Thanks.

Comment by Ranjan S on 20 Sep 2015

Well, none of those dates are going to be really good viewing. But 1st tour on the 22nd...In Fajardo, only 1 kayak company goes on Sunday but I think on Vieques they all go. Or the 1st tour on the 26th might even be better.

Comment by Gwenn on 19 Sep 2015

Hi i am going for thanksgiving break, on 22-27. Is there a day that would be okay for viewing??

Comment by kitty on 17 Sep 2015

Well, from what I hear, the glow is not great now. Some companies are not running tours or are giving them at discount. And the moon will be 77% brightness and directly overhead at 8:30pm.... this means it will not be great viewing anyway. I think I would recommend skipping it for your date.

Comment by Gwenn on 16 Sep 2015

I am going to be in Fajardo on Sept 23rd 2015 and was hoping to do the bio bay tour. Obviously the tour operators are downplaying the effects of the algae. Has anyone gone recently to inform if there is good illumination. I realize according to the calendar that the 23rd is a bad day. Would the 6:15 or 8:15 tour be preferential? If you sincerely feel like it is not worth the effort due to algae conditions and calendar, please let me know. I appreciate your candor.

Comment by Jennifer Alpert on 16 Sep 2015

Well, the 26th early trip would be the best of those dates. I think a few of the companies use tarps, but you would have to call and ask to make sure.

Comment by Gwenn on 15 Sep 2015

If it was me, the first tour on the 21st. 2nd choice- 1st tour on 22nd.

Comment by Gwenn on 15 Sep 2015

Did the biobay/walking tour 9/10/15. Still no illumination in Fajardo. Most, if not all, commercial tours were cancelled for that weekend.The reserve is apparently checking once a week now.

Comment by jason k on 12 Sep 2015

Our family will be in Puerto Rico 12/20-12/27. Based on the calendar those dates don't seem great. We really wanted to do the electric bio bay tour because we've heard so much about it but couldn't get a reservation last time. (kayak won't work for us). Any suggestions on whether any of those dates would be better than another and if so which time? Thanks in advance.

Comment by Rick Proctor on 12 Sep 2015

The only available nights for us this December would be 12/23(most convenient), 12/24 or 12/26. All seem to be bad in terms of the moon, but would you recommend going anyway and should we choose an operator with a tarp (how do we find one)? Would the early or late trip be preferable?

Comment by Anne on 11 Sep 2015

Thanks for the info- I just read about the seaweed issue last night. But the officials didn't mention the dinoflagellates not glowing. They are taking the seaweed out, so hopefully this is just temporary.

Comment by Gwenn on 19 Aug 2015

Just did the bio bay tonight (8/18) and saw NO illumination at all. There has been a problem with seaweed and it caused the plankton to go into hibernation. This may be a short term or fairly long term (month or more) issue depending on whether the oxygen levels return to normal.

Comment by Scott on 19 Aug 2015

I would probably try for the 27th early trip. Early trips are better than later.

Comment by Gwenn on 17 Aug 2015

Yes, almost every operator goes out no matter the moon phase. Some use tarps to try to block out some of the light. There are a few Inns/hotels in the area (you can walk there from the El Conquistador), but Fajardo is only about 1 hr drive from San Juan and most tour operators provide transportation for $20, so most people don't spend the night in Fajardo just for the biobay.

Comment by Gwenn on 17 Aug 2015

We will stay at Puerto Rico at the week of Nov. 22, 2015. According to the moon calendar, almost everyday is a bad day (unfortunately, Nov. 28 is not an option to us). Because of all the good things we heard about the biobay, we still want to try our luck. So my questions is, on those bad days, what time will be relatively better? 6:00 PM, 7:00 PM or 8:00 PM? Thanks!

Comment by Andy C on 17 Aug 2015

Hello - We are planning a trip to PR and would like to see the BioBay near Fajardo. We will be there on the evening of the 23rd of Sept. And I see it is not a good time to go, but unfortunately it is the only time we can see it. Do tour operators go even during the "bad" times and if so, can you tell me one. And, where is a good place to stay over there for one night? Thank you so much!

Comment by Erica Kavadias on 15 Aug 2015

If you get the early tour on the 28th, you'll be fine. The moon rises late on the 28th ... after you would be finished with the early tour. So it only affects the later tour that night.

Comment by Ray on 07 Aug 2015

Both dates are equally bad. The 20th might be a tiny bit better ... but not much.

Comment by Ray on 07 Aug 2015

Hello, We are wondering if the November 20th 15 or November 21st 15 would be best-- both say they are not good on the moon calendar but we leave on the 22nd so those are our only options! Thank you!

Comment by Jennifer on 06 Aug 2015

We are planning a trip to Puerto Rico November 25th-30th. I see that unfortunately this is during the time of a full moon. However, on the 28th it says Good early, fair later and the 29th it says Best early, good later. I would rather book it on the 28th just in case the weather is bad and we had to reschedule to the 29th. I am a bit worried waiting until our last full day, the 29th to do the tour of the bay. Could you give me more info on if the moon conditions would be good enough on the 28th or if you would recommend doing the 29th? Thanks!

Comment by Tracy on 02 Aug 2015

You are correct- you would have to spend the night on Vieques to experience that biobay. There are electric boat sin both Vieques and Fajardo's biobays. That is an option, but the boats in Fajardo are 6 people max per trip. The other option is to do a walking tour at Las Cabezas nature reserve. It is mostly in a tram but with a walk on the boardwalk over the water.

Comment by Gwenn on 27 Jul 2015

We are a group of around 20 people with a few seniors and will be staying on the main island from August 8-12. Would like to visit Mosquito Bay. I have a few questions to plan our schedule: 1. The ferries go from the main island for Mosquito bay, but the last ferry comes back around 6:00 PM. Does this mean that we cannot return back to the main island on the same night? 2. What is the best way for the seniors to experience the Mosquito Bay as they cannot go on a Kayak?

Comment by Manny on 27 Jul 2015

We are in a VERY BUSY time of year, that week especially as there are 2 PR holidays that week. So try calling to reserve now, to see what is available. That week moonwise is tough- going on a full moon, so lots of light. First tour would be better than second tour.

Comment by Gwenn on 13 Jul 2015

Well, it is just about a full moon, so the sky will be bright. That will reduce viewing. But if the company uses a tarp, it may help. The moon won't be directly overhead, so that is a plus. Good luck!

Comment by Gwenn on 13 Jul 2015

we are visiting from 7/29 - 8/4. trying to arrange a snorkeling trip to Culebra and also a bio bay tour. it looks like our date for bio bay will be 7/30. will we be able to see any bioluminescents?

Comment by Heather McPHerson on 13 Jul 2015

I have been going to La Parguera"s biobay for the past 40 years as a tourist operator and as a scientist and I am amazed with so much wrong information given out about this biobay. I conducted a study in the bay two years ago to prove for one and for all that the bay changes every day so there are good days and bad days, This dynamic ecosystem is very sensitive to several factors including wind , salinity changes, nutrients, solar intensity, rain and so forth. all these factors interacting together create the conditions for population changes of the microorganisms in the bay. These changes are responsible for different night bioluminescence intensities. If you add dark nights, full moon nights, cloudy nights, nearby city lights then you get extra factors for its daily change. This bay is not polluted and it is an effect of its geomorphology and its location in relation to the prevailing winds that such a big population of dinoflagelates and other plancktonic organisms gather there. The bay has been overfished and the nearby cities have grown creating light pollution that also affects the human appreciation of the phenomena. But the bay can be spectacular. So take your chances,you might get lucky.

Comment by Ismael Ramos Soler on 09 Jul 2015

Our options are Jul 26- Aug 1, 2015. Which date would be preferable, or should we just wait to see if there is a cloudy day? Are we better off booking in advance, or just wait to see the weather? Thanks in advance!

Comment by Tammy on 08 Jul 2015

Of those dates, the first tour on the 28th would be better.

Comment by Gwenn on 28 Jun 2015

Hello-- we are wondering if the June 28th or June 29th would be best-- both say they are not good on the moon calendar but we leave on the 30th so those are our only options! Thanks

Comment by Ann on 28 Jun 2015

Well, unless you want to spend the night over on Vieques, visiting Laguna Grande in Fajardo is your only real choice. That can be done from SJ one evening. Either time for the trip will be great...just depends when you want to eat dinner or other plans you have that day or what time you want to get home. The 27th is a expect some weekend traffic.

Comment by Gwenn on 28 Jun 2015

Your moon calendar is very helpful. We are in San Juan the night of February 27, 2016 which is noted as Best for a trip to one of the bioluminescent bays (or bio-bays). We are both in excellent health. If you could only go on one tour, which tour and bay would you choose for that night? Would you take an earlier or later trip or will it matter? Looking forward to your additional insights. Thank you :)

Comment by Pamela Lovegren on 27 Jun 2015

Either tour will be fine that night.

Comment by Ray on 26 Jun 2015

Thanks for your useful comments. We are planning to go to Vieques on July 19th. According to the calendar, it is a good day to see the bioluminescence. I called the tour company and they have 7.30PM tour and if that gets filled, they will have 10.00 PMtour which runs till midnight. Do you have any recommendations on when to book the tour to see the bioluminescence best. We will have a 8 year old kid with us.

Comment by Dipannita Dutta on 26 Jun 2015

Depending on his handicap....If he can kayak, then you should be able to find a tour for $45. He would need to step into the kayak, so stand on one leg for a couple seconds. The guides will help. If he can't kayak, you can use one of the electric boat companies. Bio Island is easiest since they have on-line reservations. The electric boats run about $5-10 more than kayaks. Or, you can do the walking tour, which is only a little walking. That is at the Las Cabezas Nature Reserve. That is the cheapest at about $20 pp. You can read about each of these trips by click on the links in the first paragraph of this article...check the links for Laguna Grande

Comment by Gwenn on 23 Jun 2015

Hi. This post is so very long that I only read of few posts n didn't see the answer I'm looking for. My husband and I are going on our 40th anniversary cruise on 5/8/16. We arrive in SJ the evening of 5/4/16 for a 3 day stay in SJ prior to the cruise. We definitely want to do the bio bay excursion sometime during those 3 days. My brother and SIL will be with us and he is somewhat handicapped. Which tour company would you recommend for us including the most reasonably priced !! Thank you for the post and answering soooo many questions ! ????

Comment by Elaine Gee on 22 Jun 2015

Well, either day will be bright, but pick the first tour of either day so the moon is not as overhead (which happens close to 10:30-11pm)

Comment by Gwenn on 15 Jun 2015

Could you please tell if tour will go on 29th and 30th June? As per calender it will be full moon so not the best timing but those are the only two days available during the trip.

Comment by pranav bhatt on 14 Jun 2015

It will be fair viewing. The moon rises early, so it will be directly overhead during tour times. But it is only a 50% moon, so not crazy bright.

Comment by Gwenn on 07 Jun 2015

Could you please tell me if there will be too much light to really enjoy the bay during the early boat cruise on June 24?

Comment by Sarah Ciancarelli on 06 Jun 2015

Won't matter. Both will be moonless.

Comment by Ray on 23 May 2015

Which time do you recommend for June 8,2015 tour, The 6:30pm or the 9pm ? The calendar shows it is the best viewing day. Or does it matter.

Comment by Mary Anne on 23 May 2015

The calendar is our opinion on viewing....we think it is accurate. Is it worthwhile going?....again an opinion and depends on how badly you want to see it. But maybe the tour company will do something to block the moonlight, so you will see something under the tarp. Some people enjoy the experience and "see" tons, some people don't see anything and hate it.

Comment by Gwenn on 16 May 2015

We will be in San Juan night of March 25, 2016 staying one night prior to our cruise. The calendar shows this night as being "bad". the next day is "good early". How accurate is the calendar? Would it still be worthwhile to go out on the Bio Bay excursion on the 25th? Thank you.

Comment by Jung Lee on 16 May 2015

Yes, only 1 kayak company goes out into the Fajardo biobay on Sundays, so that is nice. But, the only Sunday in your date range is May 31, which would not be great viewing. It will be bright, so viewing won't be the best, but the first tour that night would be better than the second.

Comment by Gwenn on 21 Apr 2015

We will be staying in San Juan for two weeks with rental car and will be available to take a bio tour the weekends of may 30 - june 6. Which weekend would be better to see bio bay and which one is better. Also read Sundays are better days. Concerned about doing tour with too many kayaks out there Are there any companies that limit number tourists out in kayaks each time to make experience more enjoyable

Comment by Sherry Jenkins on 19 Apr 2015

I would try first for the first tour on the 27th, then the first tour on the 28th. If no other option, first tour on the 29th.

Comment by Gwenn on 18 Apr 2015

We will be in San Juan 4/25 through 5/2 which all appear to be bad days to experience Bio Bay. Sunday is fair but is not an option for us. Which day would be the best to visit? Thank you!!

Comment by Kristy on 17 Apr 2015

You are talking about Sept/Oct 2015? These dates are on this calendar and all except the 30th are great viewing nights. It is more than just moon phase that is important...when the moon is in the sky is almost more important.

Comment by Gwenn on 29 Mar 2015

We will be in San Juan a few days before a cruise ...I think moon will not be "good". Sept. 29-leave the 3rd. We were thinking about staying over a few days to get the bio experience!!! Those dates Oct 10, 11, 12. All 2015 !! What days would you suggest?? I checked the "regular" moon phase info, etc. please give info for Sept 30, Oct. 1,2, 10, 11,12. Many thanks!!

Comment by Joann on 29 Mar 2015

In order of best to worst....I would try for the first tour out on Sunday or Monday, Tuesday, Wednesday

Comment by Gwenn on 28 Mar 2015

This weekend isn't good, but it will still be busy because the holidays have started! But if you can get the first trip out on Sunday, it would be better than Saturday.

Comment by Gwenn on 28 Mar 2015

They are all great viewing nights. Pick which ever night or tour works best for your schedule.

Comment by Gwenn on 28 Mar 2015

We will be there April 10, 11, and 12. Any thoughts on which night would be best and the early or late trip? Thanks!

Comment by Janet on 28 Mar 2015

Bobbi Young, I will be in PR this coming weekend as well. Any luck with planning a bio bay tour? It's not looking good, according to this calendar...

Comment by LauraPB on 25 Mar 2015

We will be visiting from March 28th through April 3rd. None of those nights look great according to the calender but is there a night you would suggest?

Comment by Rachel Lam on 22 Mar 2015

We have never done it, but it looks great and it seems like a great idea (since seeing the luminescent organisms during a full moon is not great). They offer lots of education about the area. Check it out!

Comment by Gwenn on 19 Mar 2015

Hello! Have you ever done this full moon tour?

Comment by Becca on 19 Mar 2015

Either time will be great. Choose whichever works better with your plans (dinner/driving etc).

Comment by Gwenn on 17 Mar 2015

I'm planning on visiting the Biobay on June 5 which is a "best" night. Should I go early or later, or is any time the same?

Comment by Kathy on 16 Mar 2015

Well, none of those days are going to be great. But 1st choice, I would try for the first tour on April 5, or then 1st tour April 4.

Comment by Gwenn on 02 Mar 2015

What are the best days to go if we are only available to go on March 31, April 3, april 4, april 5 ...what time

Comment by Pershin on 01 Mar 2015

The 8th will be least crowded because only The Kayak Rental runs tour that night. But then the 9th or 10th are you next best bets.

Comment by Gwenn on 28 Feb 2015

Hi will be there mar 5-10 and wanted to go on Sunday becuz less crowded we heard - what is best night for viewing and crowds in your opinion. then we will work around those options - tks!

Comment by beth on 28 Feb 2015

Either time is great viewing, so whichever one works best with your dinner plans. The clear kayaks do sound cool...they are a new company, but have gotten good reviews so far. We used Blackbeard's, they were real good (and only 10 guests per tour). Have fun!

Comment by Gwenn on 23 Feb 2015

Hi, we are looking at going on a biobay tour on Vieques on March 9th. The calendar shows as excellent. Should we go on an earlier or later tour or does it matter for that night? Also, which is the best tour operator to use? I was thinking JAK because of their clear kayaks. Thank you! Jeff

Comment by Jeff on 23 Feb 2015

I would opt for the first tour out on Feb 28th or March 1st. 3rd choice would be first tour March 2nd.

Comment by Gwenn on 15 Feb 2015

We are arriving Feb. 28, leaving Mar 5. Is a bio bay trip still worth it? If so, what are the optimum time and place? Thanks!!

Comment by Nan on 15 Feb 2015

Currently, the only way to see the Vieques biobay is to stay overnight. Probably not worth the effort. Both bays are about the same lately. Yes, the tours will go out on the "bad" days. This calender is only my opinion, I don't think the tour companies worry too much about it. I doubt anyone will hold the last tour for you,and there are no private tours, so don't try to rush there...too much stress! I would probably opt for the 1st tour out on the 28th, 29th or 30th. Moon will be overhead, the earlier nights, but less bright. So the 30th, there will be more ambient light, but it won't be overhead during your trip. It all messes up viewing, but you can hope for clouds (or a tarp!). Many of the companies do something to help make viewing better, and at very least, you will see the sparkles in the mangrove tunnel you go through.

Comment by Gwenn on 15 Feb 2015

Well, you can hope for clouds... You are coming right at the full moon, so it is bright. But it is rising just as the first tours are going out. So it will be lower in the sky. If the company can block the light (with a tarp or something), you will still be able to see the glow.

Comment by Gwenn on 15 Feb 2015

hi im coming mar 2-6 and sadly it looks like the whole week is marked as bad. is it not recommended to go, or is it still possible to see the organisms light up? what are your recommendations please? thank you

Comment by sophie on 15 Feb 2015

Hi There, I have been trying not to ask you any questions because you're so thorough and help so many, I didn't want to plague you with yet another question! However, I am stumped and despite reading everything here and everything I can find elsewhere on the internet, I am having a hard time making up my mind about something. I'm bringing my son to Puerto Rico. We arrive at late 3/27 (a fair day) and based on the tour schedules will miss all tour opportunities that day. The first day we could go is 3/28 (a bad day for the bio bay by your calendar, but really 'the first bad day'). We so desperately want to see the bio-bay... I have emailed all the tour operators, but can't seem to get an answer if they will run a tour 3/28 or not. So, a couple questions - does anyone run private tours? so that if we got to Fajardo on 3/27 by 9pm, that someone could take us out then? If not, the next question is - Do you know if they run tours on 'the first bad day' of the moon cycle? And if so, based on a 'bad day' (3/28), if any of the tours are running, do you think it will be worth our extra expense to go to Vieques for a tour there, or just go from Fajardo? You have said in general that Mosquito Bay is brighter, but then I read in your comments above that for awhile Fajardo was brighter, I wasn't sure if that's still the case. Thank you so much for all you do, Alexis

Comment by Alexis on 13 Feb 2015

The companies go out in the rain, unless there is severe lightning. Rain doesn't affect the glow unless it has been raining a lot (it dilutes the water). There is a chance of rain every day but it usually is just passing showers. And that area is normally very dry. Go and don't worry. Worst that will happen is you might get wet. Bring a change of clothes or towel just in case.

Comment by Gwenn on 06 Feb 2015

Hi there! We are coming next week Feb 9-13 and will be staying at Rio Mar... we are wanting to come either Tuesday or Weds night but there is a chance of rain and I have seen two different posts one saying its a good time to see the bio bay and another saying its not! What should we do? Its such a short trip what happens if it rains and we cannot reschedule? Any companies that are better to rebook or refund if you cannot go before you leave? Thanks so much!

Comment by Carlie on 05 Feb 2015

Wonderful! We will initially plan on the 28th and have the 1st as a back up just in case. Thank you!

Comment by Arlena on 04 Feb 2015

I would probably choose the 28th first tour as my first choice. The Vieques bay is brighter , so that helps too. But if you go on the 1st, I think the companies on Vieques can go out on Sunday. But I don't know that for certain. You would have to call and ask them.

Comment by Gwenn on 04 Feb 2015

Thank you for your advice!! We had thought of staying in Vieques for a couple of days so we'll have to rethink that if we decide to go on the 1st unless there is a company on Vieques that will go out on Sundays. Right now our schedule is flexible....planning everything around the bio bay...does one night look better than the other?? Your time is very appreciated!

Comment by Arlena on 04 Feb 2015

I guess the 28th on the first tour or the 1st on the first tour of the night. For the 1st, it is a Sunday, so your choice is very limited as only 1 kayak company (The Kayak Rental) goes out in Fajardo (one electric boat goes also). That is good news for less experienced kayakers because it means fewer people in the channel to avoid!

Comment by Gwenn on 04 Feb 2015

First of all, I am impressed by your dedication on maintaining this site!! It seems you have helped a multitude of people!! My husband and I are celebrating our 30th anniversary this year and decided to visit Puerto Rico for the first time. Our itinerary is arriving on Feb. 26 and anticipated leaving on March 5th or 6th. And wouldn't you know it...bad timing it seems per your calendar. We most likely will not be back to PR anytime soon so your advice will be greatly appreciated on which date or dates you believe to be the best of the "Bad" days and I will work our plans around that. Many thanks in advance for your wisdom!! :)

Comment by Arlena on 04 Feb 2015

That would be the first tour they offer. Usually about 6:30 or so.

Comment by Gwenn on 30 Jan 2015

We will be in Vieques Feb. 3, 4, & 5th - unfortunately all of the days seem to be poor for viewing. It looks like the 5th is fair early. What time do you mean by early? Do you think it's worth taking a tour at all on a "fair early" only day? I don't know if we'll ever make it back to Vieques so I'd like to try. Thanks for your help!

Comment by Lilly on 30 Jan 2015

It is only at night (the organisms glow in the dark). Occasionally at Las Cabezas nature Reserve tour they have some in bags inside, and they turn off the lights and you can see them. But you would have to call to find out if they have the organisms and then make a reservation for the tour.

Comment by Gwenn on 28 Jan 2015

We want to do this before our cruise on feb 7th but we fly in at 11:30pm on the 6th. Are there any early morning excursion option or are they all in the early evening? Thanks!

Comment by Lindsay on 28 Jan 2015

The calendar says the 8th will be excellent- that is the night I would go! Unless you are staying the night on Vieques, your only option is Fajardo bio bay.

Comment by Gwenn on 26 Jan 2015

We are interested in a kayak trip to the bio bay on March 7th or 8th, 2015. What do you recommend? Thanks.

Comment by Alex M on 26 Jan 2015

Vieques is back to it's usual glory as far as I know. If you are staying on Vieques, visit that one. If you are only staying on the main island of PR, then go to Fajardo biobay.

Comment by Gwenn on 20 Jan 2015

Hi there. I'm thinking of visiting one of the bays from Feb 13-16. According to your calendar those appear to be good days. But which bay should I visit? I read that Vieques used to be the brightest but mysteriously got dimmer in December 2014. Are there updates on that? Thanks in advance for your assistance!

Comment by Ray on 20 Jan 2015

Either time will be great the calendar says. It depends on what works into your schedule better.

Comment by Gwenn on 19 Jan 2015

Will be doing the tour feb. 8th 2015 will it be better to do the early or later tour? Thank you very much!!

Comment by Cody on 19 Jan 2015

Yes, that night is the best.

Comment by Gwenn on 19 Jan 2015

That would probably be the best night to see it. If you can get the earlier tour, it might be better. Moon is very full and bright, but only rises at 7:20 that night, so it will be low in the sky (not over head).

Comment by Gwenn on 19 Jan 2015

We will be in PR March 4-9, 2015. Looking at the calendar above, it appears the best night for the bio bay would be earlier on March 8. Is that correct? Thanks!

Comment by Shawna on 18 Jan 2015

Hi, I will be in Puerto Rico from March 1st to the 6th which all look like bad days!! However I still really want to see the Bio Bay - would a 7:15 tour on the 6th be worthwhile? We are doing one on a boat so it should not take us too long to get to the actual bay and we would hopefully see it before the moon rises too high. If not, what other night would you recommend? Thank you!!!

Comment by Catherine on 18 Jan 2015

I would say, try for (in this order) the first tour on the 29 or 30th, or 31st. Moon gets brighter and fuller every night after the 29th. But it will not be directly overhead during the first tours.

Comment by Gwenn on 14 Jan 2015

we will be in PR March 29th thru april 6th.. is there a day that would be better than another.. just like the previous inquiry we won't be back to PR anytime soon but don't want to miss out.

Comment by Tina on 14 Jan 2015

I would say the better dates might be the first tour on March 1st. The moon is directly overhead at about 10pm. And ask the companies if they use tarps to block the moonlight (that might help).

Comment by Gwenn on 14 Jan 2015

Hi, we'll be in PR on 27 Feb-3 Mar but based on the calendar, those nights are not ideal. We do want to experience it as I dont think we'll be back in PR anytime soon. Would it still be ideal to go and if so, which night? This is so we can plan around our dates to suit the day we'll do the biobay trip. Many thanks!

Comment by Cat on 13 Jan 2015

The only kayak company I know that goes out on Sunday is The Kayak Rental. They have glass bottom kayaks, so that is cool! But book ASAP as they are the only ones that go that night. Info here: The electric boat Baby Bay Cruisers also goes on Sunday.

Comment by Gwenn on 10 Jan 2015

This post is so helpful! We will be on the island next weekend, just before the new moon (!), and I am having a hard time finding which companies are open on Sunday nights...can you help at all? We're hoping to combine El Yunque, Luquillo and BioBay on Sunday.

Comment by Kiri on 10 Jan 2015

If you go in an electric boat, it would be ok. The baby is not allowed in a kayak. But I doubt the 2 yo would care about the bay.

Comment by Gwenn on 07 Jan 2015

Would the Bio bay be appropriate for children? The six year old would think it was coll, not sure that the 2 year old will even notice!!

Comment by Rachel on 06 Jan 2015

I guess the 28th on the early trip would be best. Moon will be almost overhead, but only 66% brightness. All the kayak companies offer transportation from SJ to the biobay for an additional fee. There is one company that did trips from PR to Vieques for Mosquito Bay. But they are currently not doing the trip due to permit issues. You can wait and see if they can work it out and restart the trip. They also will have transport from SJ.

Comment by Gwenn on 23 Dec 2014

Hello! We will only be able to visit bioluminescent bay on either March 29 or 30, 2015. I see that they are both listed as "Bad". Do you have a recommendation on which might be better? Also, what time of night? Is one bio bay better than the other? We're staying in San Juan, but I think I've heard Mosquito Bay may be better? Also, do you know if there are any companies that do trips from San Juan, or will we need to find our way to the east side of the island? Thank you!

Comment by Kimequa on 23 Dec 2014

There are 2 kayak tours per night. The early tour would be the first tour out- about 6-6:30pm. The late tour is the second tour (usually about 8:30pm). There are only 2 electric boats for Fajardo. They have 6 spots each trip. They fill up FAST! But neither have transportation available. You would have to hire a driver (not cheap) to bring you there and back....probably about $80 each way plus waiting time. Do a search on Google or Trip Advisor for drivers. It would be much cheaper to rent a car.

Comment by Gwenn on 19 Dec 2014

Thanks for having up to date info! We did this in Jamaica, but seems PR is even better! 1. Our best /only date: Feb. 6: it says good early/fair later = what time span is early? 2. Best/good tour with boat not kayak? 3. We are staying in condado area, not renting a car. How to get there and back? Taxi? Tour guide? How much should we pay for that part of the transportation, and would they hang around, or come back and get us? Thanks!,,,,,!

Comment by Kimberly on 19 Dec 2014

IO PR Eco-Tours/The Kayak Rental — They go 6 days a week, including Sundays! 787-616-9594 or (787) 613- 3928 or email them at They can arrange transportation. I would go on a Sunday with them (unless you don't want to kayak). The darker the night the better, though sometimes the companies that go out on nights with the bright moon usually bring tarps or something to try to block the light. Sunday will be less busy also- fewer kayaks bumping to you.

Comment by Gwenn on 13 Dec 2014

We will be in San Juan for cruise and will have only one night (2/28/15) before and one night after (3/8/2015) staying in San Juan. According to your calendar, 2/28 would be a bad night. 3/8 (Sunday) would be a good night. However, it seems no body offer tour on Sunday. Do you know if any one conduct tour on Sunday? Or should we just take chance and go on Feb 28 and hope for a cloudless night. I called Bioisland and they told me that they go out every night (except Sunday) regardless moon phase. They told me that you can never predict which night is good or bad. Please help!

Comment by Ying on 12 Dec 2014

You can always get a taxi to the ferry (about $80 each way). The ferry is different from excursion boats. I will assume you want to do East Island biobay tour. EI offers transportation (for a small fee) to their excursions (not the ferry). But right now they aren't running the biobay trip due to pending permitting paperwork.

Comment by Gwenn on 10 Dec 2014

Is there transportation from San Juan to the ferry? If so, is it included or should I contact a different company for this? If I should contact a different company to drive us to the ferry, can you recommend someone? Do you know if it is possible to make reservations at East Island? Thank you.

Comment by Misty on 10 Dec 2014

Yup! Go on the 8th.

Comment by Gwenn on 07 Dec 2014

we are going to vieques jan 3 to jan 9, 2015. would Thursday jan.8, 2015 be the best night to take a bio-bay tour?

Comment by claire on 07 Dec 2014

Well, the 7th or 8th would be better bets, but still not great. I would ask the tour company if they do anything to block the moonlight (tarps etc).

Comment by Gwenn on 06 Dec 2014

Yes, the 5th would be the best chance. If it is too bright, many of the tour companies use tarps to block the light. You can ask if the company you want to use has them. Doing the Fajardo biobay is easier and cheaper for people staying on the main island of PR.

Comment by Gwenn on 06 Dec 2014

Any of those nights would be great biobay viewing. I would try to go during the week as on weekends (Fri and Sat) more locals go, so it is more crowded. For the water sports- PR is a tropical island- we have water everywhere! Take a snorkel boat trip- Go one a boat with a water slide and the girls will love all of it. Or maybe try surfing lessons or paddle boarding. We did Fly boarding, now that was water fun! But there is also sailing or even the natural water slide (weather permitting) or just playing in the rivers or beaches. Hiking to and then playing the a waterfall in El Yunque.

Comment by Gwenn on 06 Dec 2014

Either tour will be great. It is dark by the early tour, no worries. I would see what they have available...the electric boat is very limited, so they fill up fast.

Comment by Gwenn on 06 Dec 2014

I am planning on going out to the biobay on Dec 17th. Would the earlier tour be better (6pm) or the later tour (8:30pm), or will they be the same? I'm looking to do the electric boat tour. I'm a little worried that the earlier tour will be too early.

Comment by Kitty on 28 Nov 2014

The first trip out on the 7th would be your best bet. Ask the if company uses tarps or something to help block some moonlight.

Comment by Gwenn on 21 Nov 2014

The only time I could get off to travel was the 5th to the 8th of December. I was looking forward to the bio bay trip and now that I stumpled upon this site and the moon calendar I’m kind of bummed. Any suggestions?

Comment by Joshua on 20 Nov 2014

Most people go to the Fajardo biobay- it is closer/easier and cheaper than getting to the Vieques biobay. The drive to Fajardo will take about 1-1.5 hrs, depending on traffic. You can drive yourselves, or many of the tour companies can provide transportation. If you want to go to the Vieques biobay, you need to go with East Island excursions. They are the only ones that can do it in one evening.

Comment by Gwenn on 19 Nov 2014

I will be visiting PR 12/7-12/10. I wanted to visit one of the Biobays... I was planning on going the 9th as it seems it will be a good day to go. Which bay do you feel is the best to visit? Also, I am staying in San Juan so if you could share the distance to the bay you suggest, it would be helpful. Thanks, Nicole

Comment by Nicole on 18 Nov 2014

Have a week in PR 2/18-24, 2015. Which is the best couple of dates to see bio bay for family of 4 (2 kids 9, 11). What would you recommend for adventurous water girls? Thank you!

Comment by Bamboo on 04 Nov 2014

We will be in PR from Feb 2-5, 2015. According to your chart, the early tour on the 5th may be our best chance (albeit not great). We were thinking Fajardo. Any suggestions?

Comment by Sally on 29 Oct 2014

The only time I could get off to travel was the 5th to the 8th of December. I was looking forward to the bio bay trip and now that I stumpled upon this site and the moon calendar I'm kind of bummed. Any suggestions?

Comment by Joshua on 24 Oct 2014

Early tour if you can do it, but later will be ok too.

Comment by Gwenn on 14 Oct 2014

Hi Gwenn, Thanks a lot for the suggestions and we will go Fajardo biobay on Nov 28th. Is it better to have a late night tour or early night tour on that day?

Comment by BIKE on 14 Oct 2014

Well, if it were me, I would do Fajardo biobay on the 28th. It is not possible to do the Vieques biobay on your own on the 28th- too rushed for time. You could check with East Island Excursions if they could get you there that night (but I think no). The 7th seems too bright to me- The moon rises at 7pm and it is 99% full brightness.

Comment by Gwenn on 14 Oct 2014

Our family will have a cruise vacation and will stay in San Juan at Nov. 28, 29 and Dec 7. Unfortunately, they are not perfect days for bio bay tour but that's the best we could do. Our flight will arrive SJU at 3PM. The ferry to Vieques is on 4:30PM and 8:00PM. Is it possible for us to catch the Vieques bio bay tour on Nov 28 (the only good day)? If not, do you suggest the tour in Fajardo on Nov 28 (good day) or the tour in Vieques on Nov 29 (fair day)? The moon calendar on says Dec 7 is a good day, which will be perfect for our travel plan if it is true. Do you have any suggestion on it? Thanks a lot for the help.

Comment by BIKE on 13 Oct 2014

The bays are back to normal. All recovered! So as long as there are no setbacks, Vieques bay is brighter than Fajardo.

Comment by Gwenn on 11 Oct 2014

Hi Gwenn and Ray, How are the biobays recovering this year? We are going between Nov 15-22nd. All are great nights. But we are trying to decide between taking a electric boat to Mosquito biobay or kayak at Fajardo biobay. Is the Mosquito bay much brighter than Fajardo bay this year? Thanks!

Comment by Shenna on 10 Oct 2014

You have to visit the biobay after dark. This time of year (September), it gets dark around 6:30pm ... so I imagine the first biobay tours would start out around 6pm.

Comment by Ray on 20 Sep 2014

Hi, We are visiting pr next week september 19th. Can you tell me what times do the tours start for bio bay?

Comment by on 14 Sep 2014

All great nights means no real difference in viewing since the moon is out during that time. Go when it is convenient for you. I would try to go to the Vieques biobay while you are there.

Comment by Gwenn on 13 Sep 2014

Hi, We are visiting Nov15-22 2014. Looks like these are all great nights to see the biobay. I am wondering if there is still ant difference between these nights. Is it the later the better? We may be able to visit Vieques during our first couple nights but not sure if we should wait till later in the week.

Comment by Shenna on 13 Sep 2014

Best option (though they all are not good) would be 1st trip on the 4th. First trip on the 5th would be second choice.

Comment by Gwenn on 12 Sep 2014

Well, they all are not great. The first tours on the 30th or 31st or the 1st. Ask if they use tarps or something to help block the sunlight.

Comment by Gwenn on 12 Sep 2014

We are planning a trip to Fajardo, PR from Dec. 30, 2014-Jan. 6, 2015. Unfortunately, the moon will be full most of those nights. In your opinion, which date and time would be best to take a bio-bay tour?

Comment by dawn stear on 10 Sep 2014

Wow- none are going to be great. If you can get it- the first tour on the 4th would be the best. If that is not available, the first tour of those nights would be better than the later tour. Also check that the company you will use does something to block the light- maybe a tarp or something.

Comment by Gwenn on 08 Sep 2014

Hi I will be in PR from oct 4-6,2014. Which night should is my best option? Should I take the early or late trip? Thanks in advance!

Comment by Ray on 07 Sep 2014

Hi I will be in PR from oct 4-6,2014. Which night should is my best option? Should I take the early or late trip? Thanks in advance!

Comment by Ray on 01 Sep 2014

The 28th or 29th are the least bright days while you are there (28th being the better night).

Comment by Gwenn on 09 Aug 2014

Hi! We will be in Vieques 28th of December to the 3rd of January. Other then wishing for a cloudy night (no rain of course) what would be our best bet for the bio bay? Gracias!

Comment by Stef on 07 Aug 2014

Out of those days, the 8th is the best, and go the 1st tour possible. Moon rises at 5pm, but it is bright. But it will be closer to the horizon during the first tour.

Comment by Gwenn on 06 Aug 2014

we are going to pr and staying in san juan. want to see the biolum bay but of course...full moon. we are there august 8,9,10 as our full days. which would be best or is it not even worth going to see ..(would prefer to go 9th or 10th as our first full day is 8th)? thanks

Comment by ira on 06 Aug 2014

Either week is great for viewing the bays. Rain-from my experience, we usually we get more rain starting later in Novemeber. But you can never tell with the weather! November still has a possibility of hurricanes, but it is not too likely. Choose whichever week works best for your schedule. We have a holiday in either week (Veteran's Day and then Discovery Day).

Comment by Gwenn on 02 Aug 2014

Hi we are planning to visit PR to see the bio bay on either the second week 10-15 or third week 17-21 of November 2014. The second week is just after the full moon . Would the third week be better? Will there be a lot of rain in November? Thanks!

Comment by JoJo on 02 Aug 2014

Try to get the first trip on the 7th, or maybe the 8th. After that the moon is brighter each night. And pray for a cloudy night!

Comment by Gwenn on 24 Jun 2014

For the electric boats, it is best to call them. Emails are not their thing. I believe Suarez goes out on Sunday nights. But try calling a few times if you can't get through to a person (messages are not always answered)....they are sometimes hard to get in touch with!

Comment by Gwenn on 24 Jun 2014

We kayaked Fajardo in 2008 and loved it so much we want to take my motherinlaw. We will be cruising so our dates are limited to Saturday. 7/12 or Sunday 7/20. Wanted to walk into Laguna grande but it appears they are closed Sunday. Mom is 78 so we considered electric boat, but they are not offering July tours on website. Emailed captain Suarez but no response. Any suggestions? We really want to do it Sunday so we can show mom osj Sunday morning and stick to osj befor cruise departs. Any suggestions? Thanks in advance!

Comment by Sharon on 23 Jun 2014

We are coming to Puerto Rico on July 7 - July 12. I have looked at the moon calendar and it is showing bad for viewing. I'm so disappointed, any suggestions? Thanks!

Comment by Julie on 22 Jun 2014

I hope you were able to call them directly and get a reservations. They sell out quickly.

Comment by Gwenn on 21 Jun 2014

Hi, I wanted to book for June18th or 19th on the electric boat since I am not an experienced kayaker. What time would be best and how far are you from the airport?

Comment by Seema on 12 Jun 2014

Go on the first (early- around 6:30-7pm)) trip on the 7th.

Comment by Gwenn on 03 Jun 2014

Hi, I want to book a tour for the 6/7 or 6/9 this coming week. The calendar says that those days are bad for viewing, but out of those two dates which one is the better day to do it?

Comment by Sarah on 03 Jun 2014

It is not the best for viewing- call ahead to make sure they are going out those nights (some don't go if the moon isn't right). The 5th is better than the 6th.

Comment by Gwenn on 27 May 2014

Hi Gwenn, thanks for posting this. We are planning to go to Vieques on July 5th or 6th. Is that a bad time?

Comment by Steven on 27 May 2014

You need to change the location to San Juan for the moonrise chart. So on June 13th, the full moon will rise 7:39pm. The fist tour would be pretty good that night since the moon will be lower in the sky.

Comment by Gwenn on 21 May 2014

Thank you for posting this! I was hoping you could help us too: we are going June 8-14 (worst time for Bio Bay!) but for June 13th, this link says that moonrise is at 9:37: If we go on the earlier tour, will we be able to see the bay light up, since the moon rises later?

Comment by Katerina on 20 May 2014

The first tour Friday would be better viewing since the moon comes up later, after the tour.

Comment by Gwenn on 06 May 2014

Thanks Gwenn, would you think it makes more sense to go on Friday?

Comment by Dimple on 06 May 2014

Well...the almost fill moon will rise at about 8pm, so the first tour would be the best that night. The sky may still be very bright before it comes up, but it will probably be ok.

Comment by Gwenn on 05 May 2014

We are planning to visit Puerto Rico from May 12th to May 17th and planning to go to Fajardo bio bay on May 15th, did not want to go on May 16th since it was close to the end of our trip. Do you think it is worth going to the bay on the 15th at 6pm or should we go later in the evening?

Comment by Dimple on 05 May 2014

Even at 60%, the Vieques biobay is the brightest around. Well worth going. However, if you mean May 11 of 2014, the moon will be really bad for viewing. I am not sure anyone goes out on bad nights, but you can call and ask. I am not sure going to any biobay when the moon is that bright and overhead is worth it.

Comment by Gwenn on 02 May 2014

We are planning to go to the Biobay in Vieques Island on May 11 and stay there that night. I was told that they are currently experiencing some problems with the bay and it is about 60-75%. Is it still worth going? We want to take the Kayak tour. Thanks

Comment by Claire on 01 May 2014

While they are all not good, if you go on the earliest tour on the 10th, the moon will be least bright. Or the earliest tour on the 13th, the moon will be lower in the sky (though brighter).

Comment by Gwenn on 01 May 2014

Our trip is May 10 - 14 which is a bad time for the moon. As this seems like an incredible experience I’d like to go one night and hope for clouds! Would you recommend a certain night or time of night to go during those 5 days? Do you recommend early tour or late tour? Thanks in advance

Comment by Joe on 30 Apr 2014

I have heard they are about the same right now, but Mosquito Bay should continue to improve, making it brighter every day.

Comment by Gwenn on 10 Apr 2014

thanks a lot. I will go on 18th. I would like to know which bio bay is brighter right now. Mosquito Bay in Vieques or Laguna Grande in Fajardo? or they are about the same after what happened to Mosquito bay.

Comment by june on 09 Apr 2014

The 17 or the 18th would be the best. Who you go with depends on how you want to experience it and which bay you want to go see. There is the bay in Fajardo, which can be done on a kayak, electric boat or walking, or Vieques Biobay, which has to be done with East Island Excursion (unless you want to stay on Vieques overnight). This article should help you:

Comment by Gwenn on 09 Apr 2014

we will arrive San Juan on 4/11 night and leave 4/19 early morning and we come to see the biobay. could you give us a recommendation on the night , the bay and the company that we should go for? we will plan the rest of our trip around this. Thank you!

Comment by june on 08 Apr 2014

According to the calendar, yes, the 19th is a great night to see the biobay. We have used Kayaking Puerto Rico and liked them very much.

Comment by Gwenn on 07 Apr 2014

We want to do a Bio Bay tour on April 19, 2014. Will this be a good night and what company do you recommend? Thank you

Comment by Erin on 07 Apr 2014

Ouch. Well, the moon will be directly overhead at 9:16pm on the 10th. It will be 82% bright. The 11th, it will be overhead at about 10pm, but 90% bright. I guess I would say go to the 1st trip on the 10th or the 11th. You could ask if the operator uses a tarp to block some of the moonlight.

Comment by Gwenn on 07 Apr 2014

We're here now. The only days available for us to take the bio bay trip are the 10th and 11th. Any advise for our best opportunity to see the bay? Thanks, Mike

Comment by Mike on 07 Apr 2014

I would try the 7th in Fajardo (currently the Vieques BioBay is not sparkling well). Ask if the company uses a tarp or something to block the moon light.

Comment by Gwenn on 23 Mar 2014

We will be staying near Fagardo on April 7th, 8th and 9th - all bad nights as per the calendar. Would hate to not try it so when and where would you suggest? Thanks

Comment by Bernie on 23 Mar 2014

May has always been one of PR's rainiest months. But you never know. Vieques gets less rain than other places in PR, so there is no telling if rain will be a problem. Pick you travel dates and hope for the best.

Comment by Gwenn on 21 Mar 2014

We believe it will be a fair night (not good or great) because of the time the moon rises. The moon will be about 60% bright and directly overhead at 7pm. :-(

Comment by Gwenn on 24 Feb 2014

We plan a trip for March 27 2015. Can you give me any idea if the bio luminous kayak experience will be poor because of the half moon phase?

Comment by Bobbi Young on 24 Feb 2014

There will be lots of moonlight. Some companies don't go at all, some go but use tarps to block the light.

Comment by Gwenn on 28 Jan 2014

I was planning on going March 17, 2014... Is this a bad day to go?

Comment by Elsie on 25 Jan 2014

We are in the planning stages of a week long trip to Vieques in May. Our anniversary falls on the 7th, which only gives us the 5th and 6th as possible days. I would consider foregoing the actual date of our anniversary in order to get to experience the best bay viewing, but if we come later in the month, won't we be increasing our chances of rainy season ruining our trip?

Comment by Maureen on 25 Jan 2014

Yes, bad timing. Go on the 9th, it would be your best hope and/or try the company with the has to help!

Comment by Gwenn on 23 Jan 2014

Our trip is Feb 9-15 which is a bad time for the moon. As this seems like an incredible experience I'd like to go one night and hope for clouds! Would you recommend a certain night or time of night to go during this week? Maybe the early tour the first night Feb 9th? Or 10th? I found a tour company that uses a tent, is that effective?

Comment by Lauren on 22 Jan 2014

Sana- you will have to contact the tour company to check if they go during full moons. We don't run the tours, we just report on our experience and give our opinions. Depending on the bio bay you want to visit, there are tours via kayak, electric boat (small ones in Fajardo, a larger one for Vieques), and there is even a walking tour at La Cabezas to see the bay on foot. In Parguera they still use motor boats and have them in small and large sizes.

Comment by Gwenn on 14 Jan 2014

Hi we are going to Vieques from the 14-17 Feb which all seem to be full moon nights. Will you guys be having bio bay tours in any of those nights? Also is the tour only offered by kayak or a small group boat - I dont know how to swim so am a bit scared of kayaking myself in the dark.

Comment by sana on 13 Jan 2014

Yes, unfortunately, it will only be fair. The moon rises early in the day, so it will be directly overhead at 7:15pm. But I think they try to go toward the edges, where branches may block some moonlight. And you can always hope for a cloudy night!

Comment by Gwenn on 14 Dec 2013

Is Feb 7th 2014 still shaping up to be a Fair evening - our trip seems to be happening right during the poor viewing time. I didn't know how often you updated the calendars or if it is fixed. Thanks!

Comment by Susan on 13 Dec 2013

Yes, go on the first tour of the evening, which is usually around 6:30pm.

Comment by Gwenn on 09 Nov 2013

We're planning to the go to the trip on Dec 20. It shows "Best Early, Good Later". So when is the best time for it? As early as like 6:30?

Comment by Sylvia on 08 Nov 2013

thank you very much for your detailed info! it will definitely help us plan our trip. with the government shutdown, it now seems we will have more time since many things could be closed. all of this will be good to know. many thanks again!

Comment by laura on 09 Oct 2013

Well, it is a full moon, but if you really want to do it, I would go on the first tour of the night on Saturday the 19th. The full moon rises at 6:30pm, so it will not be overhead then and maybe the trees will block some of the light. You can always hope for clouds!

Comment by Gwenn on 01 Oct 2013

we are planning to stay a few nights in PR before our cruise departs from the island: oct 18-20, 2013. this is a full moon, and the aftermath of a full moon. would you advise to go friday (18th), saturday (19th), or will it really not be optimal viewing this time? we have waited two years to do this, and are disappointed it's during a full moon. thank you!

Comment by laura on 29 Sep 2013

The difference is ours is a baybay viewing calendar and the other is a moon phase calendar. We take into account the time of the moon rise and how much light there is and how it will affect viewing. The 26th will be great night for the biobay. Yes there is a large moon, but it only rises at 10pm. So it won't be very bright during biobay trip times, especially not for the first trip out.

Comment by Gwenn on 24 Jul 2013 Why does this lunar calendar look so different from this lundar calendar Is July 26 2013 a good night to do bioluminescent kayak tours or not?

Comment by Jeff Robinson on 23 Jul 2013

while I have heard that also, the night I went was a cloudless full moon night and our excursion leader @ fajardo said he had never seen the biobay so bright, and it was stunning!

Comment by Rebeca on 26 Jun 2011

Dec 21, 2010 is the night of the full moon. In general, this would be a bad night. Depending on the time and duration of the lunar eclipse, it may or may not be a good night to go to the biobay.

Comment by Ray on 24 Oct 2010

We're considering going on Dec 21 when the moon is full, but there is supposed to be a total lunar eclipse. Will this be a good day because of the eclipse or not?

Comment by Jean on 23 Oct 2010

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