Where Is Puerto Rico?
You slide a kayak into the water with a guide’s help. Coqui frogs chirp their name as they call to each other in the trees, “Coh-KEY. Coh-KEY.” You climb in the kayak and float into the bay. With each dip of your paddle, the dark water flashes blue. Soon, the water around your kayak sparkles with a soft blue glow. It seems like magic, but it’s nature: You’re taking a night tour in one of Puerto Rico’s bioluminescent (say: buy-oh-loo-muh-NESS-ent) bays!
A bioluminescent bay (also called a bio bay) is a body of water partly surrounded by land that’s filled with tiny living things called dinoflagellates (say: dye-noh-FLAJ-uh-layts).
Bioluminescent means light created naturally by living things—fireflies are bioluminescent.
Some kinds of dinoflagellates flash with blue light when disturbed—like when a kayak paddle stirs the water. It’s thought that these small creatures light up to scare away predators, but nobody knows for sure. There are only five famous bio bays in the world, and Puerto Rico has three of them: Laguna Grande, La Parguera, and Mosquito Bay. The brightest is Mosquito Bay, by the island of Vieques (say: vee-EH-kays). This bay holds up to seven hundred thousand dinoflagellates per gallon of water! Bio bays are an amazing part of Puerto Rico, but they’re not the only thing that makes these islands unique.
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