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Bioluminescent BaysPuerto Rico

Identification key

Which bay is yours?

All three glow from the same phenomenon, but they are not interchangeable. Read the key the way a naturalist would: start at couplet 1, pick the line that fits, and follow it to a bay or to the next couplet.

1
aGetting into the water and swimming in the glow is the whole pointLa Parguera, Lajas
bSwimming is not essential; you mainly want to see itgo to 2 →
2(1b)
aYou want the brightest glow there is, and can spend a night on ViequesMosquito Bay, Vieques
bYou want the easiest trip from San Juan: no ferry, no overnightLaguna Grande, Fajardo

For the full picture

The three bays, side by side

Comparison of Mosquito Bay, Laguna Grande, and La Parguera across brightness, access, swimming, distance, price, and best use
Mosquito BayViequesLaguna GrandeFajardoLa PargueraLajas
BrightnessBrightest of the three, Guinness World Record 2006Bright, kayak tours through a mangrove channelBright, unique for allowing swimming
Access modeKayak or electric boatKayak onlyMotorboat
Swimming allowedNoNoYes, the only one of the three
Distance from San JuanRequires a ferry or flight to Vieques, plan an overnight stayAbout 45 minutes by car, the closestAbout 2.5 hours by car
Typical price range$65 to $145 per person$59 to $70 per person$45 to $70 per person
Best forThe brightest possible glow, worth the travelA day trip from San Juan with no overnight neededSwimming in the glow itself

Whichever bay you land on, check the moon calendar before booking. The bay decides the trip; the moon decides the night.