Hard (or stony) corals reproduce by releasing their eggs and sperm all at the same time. This spawning cycle is one of nature’s most spectacular events.
Once a year, on cues from the lunar cycle and the water temperature, entire colonies of coral reefs simultaneously release their tiny eggs and sperm, called gametes, into the ocean. The phenomenon brings to mind an underwater blizzard with billions of colorful flakes cascading in white, yellow, red, and orange.
In ways that scientists still do not fully understand, mature corals release their gametes all at the same time. This synchrony is crucial, because the gametes of most coral species are viable for only a few hours. The “blizzard” makes it more likely that fertilization will occur.
Based on last year’s Carmabi Research Station surveys a prediction is now available of expected times and dates that some of the more abundant Caribbean coral species will release the next generation of corals during the annual coral spawning. The dates are only applicable to the Southern Caribbean. Be aware that the coral spawning is becoming more difficult to predict each year and that this schedule of estimated spawning times provides no guarantees. To see the 2016-spawning prediction for the Southern Caribbean, see: