Lagoona Grande in Fajardo is the place where magic occurs every night.  Imagine the water sparkling like glitter as you splash your feet, or diamonds dripping from your fingertips as it cascades from your hand, or perhaps a glowing trail as you glide through the water.  These are all descriptions of the magic you will encounter when you visit Laguna Grande. 

The bioluminescence is caused by microscopic single celled creatures called dinoflagellates.  The conditions in the bay cause an abundance of these organisms to thrive and thus create the nightly magical display.  The luminescence occurs whenever the water is disturbed such as by splashing, fish swimming etc... Children as well as adults are awed by this spectacular natural phenomenon and it should not be missed when visiting Puerto Rico.

Tours to the biobay depart several times each night.  The bioluminescence is best seen when there is less ambient light from the environment.  (Sort of like the difference of seeing a firefly in dim light verses seeing a firefly in complete darkness)  It is best seen on moonless nights, however this does not mean you can not see this effect during a full moon.  The optimum days for viewing are based not only on the phases of the moon but also the actual rise time of the moon.  So for example, even if there is a full moon it may still be an optimum night depending on the time of the moon rise. (please see calendar link below for optimum nights)

The biobay can not be seen from shore as it occurs in a bay which is protected by mangroves.  To reach the bay, you travel through a channel of mangroves preferably by kayak.  There are several companies however we exclusively recommend Las Tortugas Adventures.  They give a high end ecological tour, tend to have smaller groups, and also tend to be the first group out in the bay.  (We also recommend the first tour of the evening since they leave at dusk).  This allows some light so that you can see the mangrove systems which play a large role in protecting the bay and it allows you to get a good view of the many iguanas you will see hanging out in the trees as you paddle through the channel. Once you arrive in the bay your tour guide will speak to you about the ecological process and how it occurs.  By this time you will be surrounded in darkness and the magic will begin. 

Kayaking experience is not necessary for this tour. The guides will give basic instruction prior to your trip and are available for assistance throughout the trip.  The kayaks are double open kayaks so you are sitting on top and not in a hole.  Back supports and life jackets are provided to all kayakers.  Minimum age for kayakers is 6.  It is recommended to use insect repellant without deet, wear a bathing suit or clothing and shoes which can get wet, bring a towel and change of clothes for after the trip.  Don't bother bringing a camera as you can not capture this on film.  YOu would need a VERY long exposure time, tripod, and lots of photo editing.  Cost is $45 per person payable on site by cash or travelers checks.

*As of April 1st 2007 the DNR (Department of Natural Resources) has handed down a ruling that there is not to be any further swimming allowed by any tour operator or group in the biobay.  The reason for this is because they have found decreasing concentrations of the dinoflagellates in the bay. 

If you have children under the age of six or if you have physical limitations that would prevent you from seeing the biobay via kayak, Captain Suarez does operate a motor boat tour into the bay.  Captain Suarez is a retired ferry boat captain and holds the only license to operate a motor boat tour into the Fajardo biobay. 

Special tips:

• Tuesdays are cruise ship nights so it will be more crowded as are weekends.
• Almost all companies take Sunday off
• September and October although low time for tourism are when the bays are at the peak of brightness

Please do not go to the biobay with unlicensed guides or operators.  Even though they may offer you a cheaper price, the licensed operators are trained, insured and their licensing fees pay to maintain and conserve this natural resource. 

View the biobay moon calendar

There are actually three biobays in Puerto Rico.  Brightness of the bays are calculated by the number of dinoflagellates per gallon of water.  Based on this Mosquito Bay in Vieques is the brightest with the highest concentration.  Coming in second is Laguna Grande in Fajardo, and a far third is La Parguera which is dying due to pollution (run off contamination and diesel spillage from motor boats)and also not as bright because there is more ambient light from the surrounding city.

If you are traveling on to stay in Vieques, then you should experience Mosquito bay.  There are many operators which you can obtain information about once on Vieques.  If you will be staying on the mainland, there is only one option to see the biobay in Vieques without staying overnight.  East Island Excursions does offer a trip that will get you back to Fajardo about 10pm.  For details see East Island Excursions-Vieques Biobay  

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