Acropora palmata (Elkhorn Coral)
This species (found in shallow water in 3 to 7 m, approx. 15ft) spawns on the 4th and the 5th night after the full moon. Spawning usually takes place when little pink coloured balls consisting of both sperm and eggs held together by mucus detach from the corals.
Acropora cervicornis (Staghorn Coral)
This species is also found in the shallows like Elkhorn and its spawning occurs on the 5th and 6th night. This species also produces sperm/egg packages which come out of the corals' tissue and float to the surface where they fall apart because of the water movement. When the sperm and eggs are released from the packages they meet with either sperm or eggs from other colonies and fertilization takes place. The fertilized eggs then transform into free-swimming larvae, called "Planulae".
Diploria labyrinthiformis (Grooved Brain Coral)
Diploria strigosa (Symmetrical Brain Coral )
This Brain Coral spawns during the first spawning as well releasing sperm and egg packages a little earlier in the night than the Staghorn and Elkhorn, generally on day 7 after the full moon.
Montastrea cavernosa (Great Star Coral)This species, easily recognised by its large polyps, spawns during both spawning rounds on the 5th and 6th day after the full moon. Since Great Star Coral colonies are either male or female the release be either sperm or eggs. The release of sperm looks like a cloud which is expelled by the coral. This may last up to 15 minutes. The eggs released by the female colonies look like the sperm/ egg packages of the previous species, but a little bit smaller.
Montastrea annularis complex (Boulder Star Coral)
This is the most abundant coral in the reefs around Curacao and because of its large colony size it will be one of the most spectacular species that can be seen during the spawning on day 6 and 7 (and sometimes later). Just before the spawning takes place one will see the sperm/egg packages occur under the mouth-opening in the corals' tissue ("Setting Stage"), after which they are expelled ("Birth Stage"). The packages will stay near the colony for a while ("Gliding Stage") and will gradually start floating towards the surface ("Upward Stage"), where they fall apart ("Bursting Stage"). If one colony starts spawning, this often triggers other colonies to do the same and soon after the entire water column will be full of sperm and egg packages. Normally the spawning of this species starts with the colonies growing in deeper water (60ft) after which the colonies on the reef flat will follow.
Eusmilia fastigiata (Smooth Flower Coral)This species can be distinguished from all previous species because of its reproductive mode. The colonies of this species release full grown larvae instead of sperm, eggs or a combination of both. This means that fertilization took place earlier by the intake of sperm from other colonies. After the fertilization larvae develop themselves within the mother colony and gather in the tentacles. Most of the larval release can be seen from day 6 till day 9 after the full moon, but before that the larvae can be seen as little white balls (1/32'') in the transparent tentacles of the mother colony.
Madracis senaria (6-Ray Star Coral)
This relatively small encrusting species releases larvae like the previous species that swim immediately using small hairs on their body surface. Release takes place during day 8 and 9 after the full moon of both spawning, yet the time of the release is presently unknown.
Agaricia humilis en Agaricia agaricites (Lettuce Corals)
These two species are from the same family and both spawn several months a year including the month of September- November, which means they may be seen spawning during the mass spawning. Both species produce larvae that are released during the entire night although they are small (1/64'' and 1/16'' respectively) and therefore difficult to spot.
Stephanoecoenia michelini (Blushing Star Coral)
Like Great Star Coral this species occurs either as male or female colonies. However, sometimes both sexes are found within one colony. This means that a cloud of sperm can come from the same colony releasing eggs a little bit later or earlier. The time difference between the release of male and female gametes prevents self-fertilization, which would result in inbreeding. Spawning is expected generally day 5 and 6 in September and October. The species can be found along the entire reef-slope.
Gorgonacea (Gorgonians)
Although little is known about the spawning behavior of this species, spawning occurs in the early evening around about 19h00 when large clouds of small larvae are released resulting in a murky appearance of the water surrounding the colonies.
Echinodermata (Echinoderms)
Several species of echinoderms will release their gametes together with the spawning coral. This process is often seen as a little cloud of very small balls (eggs or larvae) that are released into the water. Some species start spawning already during the day. Long Spined Urchin and Donkey Dung Sea Cucumbers spawn around noon and dusk respectively. Brittlestars spawn in the early evening between 19h30 and 20h30 when they leave the recesses where they hide during the day, gather on top of the reef (sometimes 10 to 15 individuals on top of each other), and release their gametes into the water.
Annelida (Segmented Worms)
Fire Worms spawn during the day starting at noon. Fire Worms are easily recognized by their brown/orange color with white bristles along their entire body. They leave their hiding places on the reef and go to higher parts of the local reef where they release their gametes after extending themselves in an upright position. Xmas Tree Worms spawn around 19h00.