PICTURE YOURSELF ON A MOONLIT EVENING CRUISE, and you see the water below your boat sparkling like the stars in the sky above. This magical light show is not just a fantasy -- it's a rare phenomenon that occurs in what's called a bioluminescent bay, where you witness tiny lights that twinkle beneath you. Dip your oar down into what looks like static electricity in the waves or fling a handful of water into the air and it feels like you're sprinkling stardust.
Bioluminescent bays are created by tiny algae called dinoflagellates. These microorganisms produce a neon blue-green light from a chemical reaction involving a compound called luciferin, named for its devilish glow. According to Smithsonian Magazine, "Bioluminescence can serve a variety of purposes, such as signaling predators to stay away or beckoning mates to come closer."
Depending on the moon's cycle, weather conditions and the disturbance of waves, you can catch this amazing experience at the following destinations. Some say a full moon is the best time to visit these bays.
Where the Martha Brae River meets the Caribbean Sea, shallow layers of salt and fresh water converge into a spectacular creation. Regarded as one of the brightest in the world, Jamaica's Luminous Lagoon radiates as the water fills with phosphorous and illuminates when disturbed. Stretching along the marshlands of Trelawny, this lagoon once housed an 18th-century wharf where English vessels delivered goods. Years after Jamaica's thriving sugar trade ended, glowing microorganisms were discovered within the warm waters.
Visit Glistening Waters Hotel & Attraction in Falmouth, which boasts luxury accommodations, lagoon tours, a restaurant, pool and marina.
Where to Dock: Glistening Waters Marina
Grand Cayman, Cayman Islands
Witness high concentrations of phytoplankton shooting off tiny bursts of light in this region. These aquatic sparks last merely a fraction of a second, but when this occurs, the colors of the bay sync for a stunning light show. Located on the north side of the island near Rum Point, discover this hidden gem about 45 minutes from Seven Mile Beach. Take the short route from Starfish Point or challenge yourself by kayaking 2.5 km from Kaibo Beach Bar. Plan a bio bay adventure around the moon cycle with Cayman Kayaks, the original tour operator of the Bioluminescent Tours in Grand Cayman.
Where to Dock: The Barcadere Marina
Lajas, Puerto Rico
There's just something mesmerizing about the waters of Puerto Rico. The island is a treasure trove when it comes to bioluminescence as it is home to three active bioluminescent destinations. On the island's southwest side, just a two-hour drive from from San Juan, explore this twinkling bay along the town of Lajas. When the waters of this coastline are stirred up by waves, the dinoflagellates are at an all-time high -- a common occurrence here.
You'll witness a natural light show as you venture into the dark on a nighttime tour.
Paraguera Watersports offers a special tour where you can enjoy a sunset swim along the cay before kayaking to see the bio bay when the light fades. This is the only location where swimming is allowed.
Where to Dock: Marina Pescaderia
Fajardo, Puerto Rico
On the other side of Puerto Rico lies Laguna Grande's seaside sanctuary. On the way to your bioluminescent quest, check out three destinations: El Yunque, a nature preserve and towering mountain, Liquillo Beach, a lively beach town with great local food in bodegas and cantinas that line the street, and Fajardo, a quaint fishing village. The town of Fajardo is surrounded by beaches and nature preserves that swell with marine wildlife including dolphins, manatees and turtles. The stunning landscape exposes dry forests and lovely shorelines to explore by day, and a glowing bio bay to explore by night.
Check out Puerto Rico Bio Bay Tours for full moon kayak adventures. Witness the moonlight glimmer across the bay's bioluminescent activity as you paddle through mangrove forests.
Where to Dock: Puerto Del Rey Marina
Vieques, Puerto Rico
Also known as Bahía Bioluminiscente, Mosquito Bay is on the southern coast of Vieques, one of Puerto Rico's eastern islands. Many consider this destination to be the brightest bioluminescent bay in the world, containing up to 700,000 tiny dinoflagellates per gallon of water that live in a bay with a narrow mouth that prevents them from washing out to sea.
Unlike Laguna Grande's full moon tour, it's best to visit during a different lunar cycle when the glowing micro-organisms are more visible. Book a two-hour Bio Bay tour in a transparent kayak with Taino Aqua Adventures, located in Esperanza, Vieques.
Christiansted, St. Croix
St. Croix is home to beautiful beaches, but this hidden gem is unique among the Caribbean islands. The historic park and preserve at the northern tip of the island sparkles depending on the night and location. In addition to spotting the common dinoflagellates, witness two other types of radiant creatures here: glow worms and ctenophore (comb jellyfish).
Departing from Salt River Marina in Christiansted, get an up-close-and-personal view of the aquatic wonder with See Thru Kayaks VI's nighttime journey along the Salt River Bay on the island's only transparent kayak tour.
Where to Dock: Green Cay Marina at Tamarind Reef Resort
Though not as commonly known and not necessarily large enough to be considered bioluminescent bays, if you visit the right place and the right time, you may catch a glimpse of bioluminescent activity at the following U.S. locations: