ORA coral spawning event

[Tomoko Schum]

On September 23rd, 2013 we observed another spawning event on our coral greenhouse. At approximately 7:45pm nearly all fragments of our Blue Voodoo (Acropora sp.) spawned. These corals are split up into multiple tanks and isolated systems yet their spawn was still synchronized.

[video=youtube;ZP3dqyuvIB4]http://www.youtube.com/watch?v=ZP3dqyuvIB4&feature=youtu.be[/video]

 

[AsphaltPays]

Wow.That's really amazing!

 

[Tahoe61]

Amazing.

 

[joejoe1055]

very neat

 

[OceanLife]

Awesome!

 

[Connie]

Very nice! Thanks for sharing.

 

[Chameleon]

cool!

 

[Bubbles_B]

just eggs???

 

[Tomoko Schum]

Corals are simultaneous hermaphrodite. Each coral develops both eggs and sperms.
Here's an except from an article by Dr. Richmond of University of Guam:

"On the night of spawning, soon after sundown, the flower-like polyps which make
up the living coral colony begin to expand, as sperm packets are moved up from a
space within the underlying coral skeleton. Soon, bright orange or red eggs are
brought up and "glued" to the individual sperm bundles, until the sperm is
completely surrounded. This is a nice trick, as these clusters of 9 - 190 eggs
around a central sperm core, float to the surface due to the high fat content of
the eggs. In this way, eggs and sperm from different colonies have a chance to
intermingle at the ocean's surface, and if the combination is right,
fertilization will take place. "

 

[Qube]

Pretty amazing!

 

[Tahoe61]

After doing a little research I found a brief article that documented a spawn in Jan 2013. Was it the same coral type that spawned in January? What external and internal factors do you think are influencing these spawn events. Lastly I noticed that the moon was waning on Sept 23 rd, do you think the moon's cycle plays a part in triggering the spawning events or is that just myth?

TIA

 

[ebushrow]

Wow ... That is amazing.... Now if you could figure out how to raise the eggs ... That would be groundbreaking research and an amazing leap forward for the industry.

 

[Tomoko Schum]

Here's an excerpt from Wikipedia on coral spawning:

"Synchronous spawning is very typical on the coral reef, and often, even when multiple species are present, all corals spawn on the same night. This synchrony is essential so male and female gametes can meet. Corals rely on environmental cues, varying from species to species, to determine the proper time to release gametes into the water. The cues involve temperature change, lunar cycle, day length, and possibly chemical signalling. Synchronous spawning may form hybrids and is perhaps involved in coral speciation. The immediate cue is most often sunset, which cues the release. The spawning event can be visually dramatic, clouding the usually clear water with gametes."

Wikipedia points out about 25% of hermatypic (hard) corals are single sex corals and release gametes separately while the rest are hermaphrodites. You can see the release of sperms from a colony and releases of sperm/egg packets in this wonderful Fabien Cousteau's video taken in the Flower Garden Banks National Marine Sanctuary, in the Gulf of Mexico:

[video=youtube;CleWRmrpkJE]http://www.youtube.com/watch?feature=player_embedded&v=CleWRmrpkJE[/video]