Which bioluminescent bay is the brightest?

Mosquito Bay on Vieques, Puerto Rico is the brightest bioluminescent bay in the world, certified by Guinness with a dinoflagellate concentration that has been measured at over 700,000 organisms per gallon during peak blooms. Two factors make it dominant: a narrow inlet that traps the dinoflagellates inside, and a mangrove-ringed shoreline whose decaying leaves feed the population. Luminous Lagoon in Falmouth, Jamaica runs second — smaller per-volume concentration but easier shore access. Laguna Grande in Fajardo, Puerto Rico ranks third. The Indian River bays in Dominica and Salt River Bay on St. Croix glow under the right conditions but aren’t reliable. A Caribbean yacht itinerary can stop at all three top bays in a single week if routed across Vieques, the Spanish Virgin Islands, and Puerto Rico’s east coast. A bio-bay charter maps the route.