It is a mysterious experience as you walk along the beach on a warm summery night when sea sparkle is abundant in the water. As your foot presses down on the wet sand, you see sparks of light. Sometimes breaking waves appear as blue lines. Millions of sea sparkle collide in moving water, producing a chemical reaction which results in a greenish or bluish light. This spark is meant to scare off predators. Sea sparkle is a dinoflagellate, a one-celled organism.