Lime Cay Orgy Tonight

There's an orgy tonight at Lime Cay. There may be others simultaneously in Negril, Mobay and Discovery Bay. Organizers expect a few dozen people to show up, mostly to watch. The hard core action is an annual affair, says Judith Mendes, a marine biologist, but it only lasts about half an hour.

That's all the time star corals need to release their sperm and eggs synchronously with a velocity and volume that turns the waters around the reef into something resembling a pink snowstorm. As the gametes (egg and sperm) rush to the waters surface, their pink luminescence creates a spectacular show for surface watchers.The scuba divers under the water, however, see the best show in this annual spawning. "It's one of those experiences one never forgets," says Mendes, who lectures at UWI and is doing a Ph.D in the growth and reproduction of corals.

The corals (Montastrea annularis) time this reproduction ritual precisely with the new moon to give the gamete the cover of darkness. Mendes says scientists believe that it is so timed to elude predators. But these days predators are not the coral's only enemy. Silt, sediment and and sewage are today's main abortionists in the coral's struggle to reproduce itself.

The eggs the corals release rush madly around to mate with sperm and form larvae. The larvae must then settle somewhere so it can nurture itself. But most rocks are now covered with algae (seaweed), preventing baby corals from settling there. And sewage provide nutrients to algae that eventually smoother the coral. Elsewhere on the ocean floor, sediment robs the coral of a healthy home.

The corals release the eggs and sperm synchronously because that increases their chances of successful reproduction. The eggs have been maturing all summer to be ready for this eventful night. While scientists discovered some time ago that corals were animals and not plants, only recently have they realized that these organisms reproduce sexually like the rest of us. This mass orgy of egg and sperm was first spotted on the Great Barrier reef off Australia. Since then it has become a major tourist attraction there. Two years ago Mendes attempted to get a box seat but miscalculated the release time and saw nothing. Last year she and a couple dozen enthusiasts went to Drunken Man's Cay and were stunned by the spectacle. This year, Mendes is hoping more people find the same fascination with corals as she does. "They are the only animals that can build structures that size," she says. "They create the reef, they protect the shore line, they provide home for the fish and the sand for the beach. To me that is amazing."