Curacao: Corals Gone Wild

In Curaçao, the synchronized act of coral spawning that happens here twice annually has been studied and analyzed for more than a decade, and the result is a dive community so in tune with the mating habits of its reefs that it can predict relatively closely not only the nights each species will spawn, but also the approximate times. For divers keen to catch a glimpse of this silent act, in which coral colonies around the island release eggs and sperm simultaneously so they can mix in the water column, drift to uninhabited seafloor and grow new reefs, Curaçao is the place to be three to nine days after the full moons of September and October. "We've got the days and the times down almost to the minute," says Maryke Kolenousky, who works part-time at Habitat Curaçao and helps track the spawning each year. "Whatever kind of coral you're looking for, we've got it on the schedule."

The nights most recommended by Curaçao dive shops are usually the second or third nights, when the boulder and mountainous star corals spawn. "The star coral heads develop little orange balls inside each one of the stars," says Clark Bloom of Sunset Divers. "So if you see that, stop and wait--within the next half hour those balls will be released in what looks like underwater fireworks."

The dive shops start their trips with an educational orientation to the spawning, explaining how the different corals synchronize the release of their eggs and sperm. They show pictures of the corals expected to spawn each night and they explain how to tell if a particular coral is getting ready to let loose. Groups will often visit densely packed reefs like Mushroom Forest or Lost Anchor. Divers will spread out on their own until they find a coral that's about to spawn, and they'll sit, wait and watch with low-power flashlights so as not to interrupt the event. "The most amazing ones to see as a first-timer are the star and boulder corals that release the eggs," says Christian Ambrosi of Ocean Encounters on Curaçao. "But at the same time, you also have some kick-ass sponge spawning. There are some barrel sponges that, when they spawn, look like a washing machine overflowing with foam. It's just awesome."

InDepth

Where: Curaçao, Netherlands Antilles

When: Sept. 18 to 24, Oct. 17 to 23

Spawning Schedule: scubadiving.com/article/coral_spawning

Dive Operators: Habitat Curaçao, habitatcuracaoresort.com; Sunset Divers, sunsetdiver.com; Ocean Encounters, oceanencounters.com.