What is a Bio Bay? Bio bay refers to the Bioluminescence (bio = life, luminescence = light) single cell marine plankton known as dinoflagellates that Kayaking Laguna Grande Bio Bay in Fajardo, Puerto Rico during the new moon. Bio bay refers to the bioluminescence single cell marine plankton known as dinoflagellates that literally glow when agitated. These tiny creatures emit a greenish blue sparkle in the water when agitated by anything it comes into contact with.There are only five bioluminescent bays in the world. Join me for a kayaking tour of Laguna Grande bio bay located in Fajardo on the Northeast corner of Puerto Rico.