Coral Spawning - 2005

In the month September and October, the yearly “Coral Spawning” will take place.
Local divers talk about sex of the reefs, some mention sex on the reefs.
“Coral Spawning” is the phenomenon at which several coral species (but also other organisms) release their gonadal secretions into the water column at the same time under the influence of environmental circumstances such as water temperature and a very special position of the moon.

This phenomenon is a wonderful experience and all divers on Curacao can enjoy it. The scientists estimate the following time schedule for Curacao (12N69W):

            Full moon on Days after full moon

3 4 5 6 7 8 9

A= first spawning (Sept) Sep 18* 21-Sep 22-Sep 23-Sep 24-Sep 25-Sep 26-Sep 27-Sep

B= second spawning (Oct) Oct-17 20-Oct 21-Oct 22-Oct 23-Oct 24-Oct 25-Oct 26-Oct

1.       Scleractinia Stony corals

1.1 Acropora palmata Elkhorn Coral A ?** 21.15-21.45 21.15-21.45 ?

1.2 Acropora cervicornis Staghorn Coral A ? 21.00-22.00 21.00-22.00 ?

1.3 Diploria spp. Brain corals A ? 20.45- ?

1.4 Montastrea cavernosa Large-cup Star Coral A&B ? 21.30-22.30 21.30-22.30 ?

1.5 Montastrea annularis Mountainous/Boulder Star Coral A&B ? 21.30-22.30 21.30-22.30 ?

1.6 Eusmilia fastigiata Flower Coral A&B ? 21.15-22.30 21.15-22.30 21.15-22.30 21.15-22.30

1.7 Madracis senaria Ten-ray Star Coral A&B ? ?

1.8 Agaricia humilis/A. agaricites Lettuce Coral A&B all night all night all night all night all night all night all night

1.9 Stephanoecoenia michelini   Blushing Star Coral B 21.00-22.00 21.00-22.00 21.00-22.00 21.00-22.00 21.00-22.00 21.00-22.00 21.00-22.00

2.       Echinodermata Sea-urchins, -stars, -cucumbers

2.1 Diadema antilliarum
      Holothuria mexicana Black Sea-urchin
Donkeydung Sea Cucumber A&B
   12:00 till around 18:00, every afternoon

2.2 Ophiuroidea                                             A&B
   19.30-22.00, every night

3.       Gorgonacea Gorgonians

3.1 Plexaura Sea Rods A&B

   around 19.00, every day

4.       Annelida Worms

4.1 Hermodice carunculata Fire Worm A&B
   12.00 till around 19.00, every afternoon

4.2 Spirobranchus giganteus Christmas Tree Worm A&B    around 19.00, every night

5.       Spongia Sponges

5.1 Neofibularia nolitangere Do-not-touch-me Sponge A&B 14.00-17.00 14.00-17.00 14.00-17.00 ?

* Full moon on Sep 18 is at 2.00 am, which is actually the night of the 17th.
It may be that the spawning dates will consequently shift one night backward, i.e. for Sep 21, read 20
** Question marks indicate there may or may not be spawning on that night, unpredictable

Remarks:
First of all has to be noticed that “Coral Spawing” is a natural phenomenon and despite many years gained acquaintances there is always a chance that this phenomenon does not occur on the same place or time as divers are under water. However, it is not likely that a diver sees nothing but the spawning fierceness can vary enormously

Therefore it is important to pay attention permanently and to warn possible other divers very carefully when spawning occurs. See that you never touch the corals during euphoric movements that surely are being made while watching this wonder of nature. Remain relaxed, do not approach too close and keep an eye on surrounding presence of sperm and egg packages. Small amounts in the head of water mostly indicate that the real spawning will keep you waiting only a short time. During these nights it has no sense to go deeper than 25m. Most corals on this depth and deeper are larviparous throughout the year and they do not take part in spawning. Besides it restricts your underwater stay. Especially in the length of your dive the success of a good spawning evening is to be found. During the spawning predators will appear and they will hungrily swallow the wealth of food. Predators mostly are small sized fishes, octopus and jellyfish. Please, visit the CDOA website for checking the correct dive operators and their night dive activities, special offers and equipment.

The Above information is provided by
Dr. Mark Vermeij
Cooperative Institute for Marine and Atmospheric Studies (RSMAS/UM)
NOAA Fisheries, Southeast Science Center
75 Virginia Beach Dr, Miami, FL 33149 USA
E-mail:Mark.Vermeij@noaa.gov