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Puerto Rico has many natural wonders. From white-sand beaches to a one-of-a-kind rainforest, this is one island that will delight and inspire anyone who loves the outdoors. But you’ll have to wait for the sun to set if you want to see what might just be our most spectacular natural phenomenon: our biobays.

A biobay, or bioluminescent bay, is the result of a delicate ecosystem. Biobays flourish when tiny single-cell called dinoflagellates (pyrodinium bahamense) thrive in a protected environment. When they are agitated, the organisms release energy in the form of light. In other words, they glow, emitting an ethereal neon green aura. So does anything they touch: fish, human hands, the oars of a paddle, even raindrops.

Bioluminescence exists around the world, but there are only a few biobays on our planet… and Puerto Rico has three of them! A kayak or boat-ride away from our shores, they must be seen to be appreciated.

Note that swimming is no longer permitted in our biobays. Please help us keep these magical destinations glowing for generations to come by admiring them only from your boat or kayak.

  • Vieques Biobay

    Mosquito Bay is home to the Vieques biobay, the most brilliant bioluminescent bay on Earth. What separates the Vieques biobay from all others? It all comes down to numbers. The density of the organisms here – over 700,000 per gallon of water – is unequaled anywhere in the world. Puerto Ricans have helped keep Mosquito Bay alive and well; to this day, no motorboats are permitted in these waters.

    • Avoid the Moon

      Mosquito Bay is best enjoyed when there is no other light to minimize the bioluminescence. When you go, avoid the full moon and look for a cloudy night to get the best of this unforgettable experience.

    • Row or Ride

      There are no motorboats allowed in the Vieques biobay, but that doesn’t mean you have to kayak out. An electric pontoon boat is also available to shuttle visitors out to the bay.

    • A Bumpy Ride

      The waters of the biobay are calm and offer a relaxing ride anytime of year; however, the trip to the biobay is a bumpy one, with ditches and deep puddles pockmarking the trail.

  • Fajardo

    Laguna Grande in Fajardo is the second brightest of our biobays. Located off the northeast coast, it’s an easily accessible destination for those who want to stick to mainland Puerto Rico.

    • Avoid the Moon

      The Fajardo Biobay is best enjoyed when there is no other light to minimize the bioluminescence. When you go, avoid the full moon and look for a cloudy night to get the best of this unforgettable experience.

    • Beach and Bay

      If you want to spend the day in Fajardo, enjoy a morning at the Las Cabezas de San Juan Nature Reserve, followed by a few idyllic hours at Seven Seas Beach, before your biobay tour.

    • A Smooth Ride

      Getting to the Fajardo biobay is easy. You can drive right down to the boat ramp at the end of Route 987, where you’ll meet your tour guides.

  • La Parguera

    Head to Lajas, located in the southwest corner of the island, to La Parguera, the third biobay in Puerto Rico. While it might be the least bright in comparison to the biobays of Vieques and Fajardo, La Parguera is still only one of a handful of places in the world to earn the biobay label.

    • Avoid the Moon

      La Parguera is best enjoyed when there is no other light to minimize the bioluminescence. When you go, avoid the full moon and look for a cloudy night to get the best of this unforgettable experience.

    • Row or Ride

      You can reach La Parguera by kayak, small boat, or even a large, two-level, glass-bottom boat. This is the only bay that allows diesel-powered boats.

    • Beyond the Biobay

      La Parguera isn’t famous just for its biobay. This is one of the best diving destinations in Puerto Rico, its incredible Wall attracting divers from around the world.