Microscopic plankton called dinoflagellates grow in the shallow, brackish water of the lagoon estuary during the summer months, when the water is quite warm. The bioluminescence occurs when they are are disturbed. In other words, when the water is agitated, they light up. It's a simple explanation with a spectacular effect.
We launched just before sunset. Kayak Guy and I had recruited some friends to join us, several of whom are new to kayaking. They were understandably a little nervous about a 4-mile night paddle on unfamiliar waters, but eager to see if the experience lived up to the stories we'd told them. By the end of the evening, they were struggling for words to describe their feelings on an evening none of us wanted to end.
The weather was perfect, with just enough breeze to keep off the mosquitos. We headed north to the no-motor zone, where there is no development, not much ambient light, and lots of sea grass. As the sun set, we noticed the froth from our kayaks and paddles beginning to glimmer. Darkness fell, our eyes became better adjusted to the lack of light, and we saw more and more of the sparkle.
Each little wave from our kayaks, each splash from our paddles was outlined in light, transporting us back to the wonder of childhood. Laughter rang out. Excited voices called across the water. Some of us paddled quickly, startling the mullet, which zoomed away from us in glittering streaks.
Many mullet jumped into the air -- they tend to do that -- and a few jumped into our kayaks. There were some screams but no one panicked as the mullet were rescued and returned to the water. I was lucky that my northbound encounter with a southbound mullet resulted only in a smack in the chest, not a smack in the face. He/she bounced off and splashed to safety.
One friend paddled away from the group and glided into the center of a pod of five sleeping manatees. By the time he saw them, there was nothing he could do but hope for the best -- they are gentle but powerful and can easily tip over a kayak. As the huge mammals awakened and churned the water in surprise, their hurried retreat created a dazzling burst of light, with each creature sheathed in the brightness.
Meanwhile, I dipped my hand into the water. It came up bearing what looked like a handful of stars, glittering against my glove as millions of tiny organisms winked their light.
And over us all hung the Milky Way, with Venus, Jupiter, and Mercury bright near the horizon, connecting us with the infinite cosmos.
Light above, light below, magic in the middle.