Mosquito Bay (Bioluminescent Bay)

Puerto Rico


Natural Wonder

Hidden away on the small island of Vieques, about 8 miles from the Puerto Rican mainland, is the mysteriously glowing Mosquito Bay, also known as Bioluminescent Bay. This tropical beach is perfectly lovely during the day, but unlike most other Caribbean beaches, it attracts many more visitors at night.

That’s because it’s home to a stunning natural wonder—a sea of tiny creatures that light up the bay in surreal blues and greens.

Though it sounds unbelievable, it’s true: Visitors to Mosquito Bay can swim in the waters while the eerie glow surrounds their bodies.

How is the Bioluminescence Possible?

Mosquito Bay is the thriving home of millions of dinoflagellates, organisms that produce a burst of light when they come into contact with other organisms.

In just one gallon of bay water there are more than 700,000 microscopic dinoflagellates, and in 2008 this bioluminescent bay was recognized by the Guinness Book of World Records as the brightest recorded in the world.

Tips for Visiting Mosquito Bay

If this awe-inspiring curiosity has you entranced, you’re not alone. Travelers love to make the trek here to experience it firsthand. The easiest way to get to Mosquito Bay is to book with a tour operator, which can cost up to $60 per person.

It’s best to explore the bay by kayak, as motorized boats will likely cause too much of a disturbance. Remember, too, to avoid the bay during a full moon or on bright nights, so you can view the bursts of light in total darkness. And skip the bug repellant—it can kill the dinoflagellates.

Mosquito Bay (Bioluminescent Bay) at a Glance


Country or State:Puerto Rico

Access:By boat, ferry or plane

Best time to visit:April to June

High Season:December to May

Low Season:April to November


  • Restaurants in nearby villages
  • No lifeguards
  • No public restrooms

Beach Type:

  • White sand
  • Saltwater
  • Secluded