As a matter of a fact, sea does sparkle indeed ! Recently, at night, our guests have been noticing glowing dots where the waves break on the beach. On some nights hundreds of these small planktonic creatures, each no bigger than a grain of sand, illuminate in electric blue as they are physically disturbed by the breaking wave. The organism causing this glow is Cypridina ostracod, (a planktonic creature). This glow, is called bioluminescence, and Cypridina glows when it is disturbed.
So why glow at all?.. It is thought that Cypridina flashes to confuse or scare away its predators. However the purpose of the flash may be even smarter: this flash may help it to attract bigger predators to eat Cypridina's predators, just like a burglar alarm that alerts the police to come to someone’s house to catch a robber.