|"BOOM! What a remarkable thing to witness!"|
says Debby Ng of the Hantu Bloggers
What is coral mass spawning?
Some corals release their eggs and sperm all the same time. Called broadcast spawners, these mass spawning events usually occur once a year, a few nights after full moon. The eggs and sperm drift to the water surface where fertilization occurs.
|Photo by Toh Chay Hoon on facebook, of spawning, |
s well as other cool critters that only she can spot
at Pulau Satumu, Raffles Lighthouse
While bazillions of eggs and sperms are released during a mass spawn, most don't make it. Hordes of marine creatures gorge on the spawn, from fishes and crabs to jellyfishes. As the tiny coral larvae develop, they have to survive the countless predators that constantly sieve the water for plankton and edible bits. As well as many other challenges that we are still learning about. Excessive sedimentation, for example, can interfere with fertilisation and other aspects of coral larvae survival and successful settlement.
Why is coral mass spawning in Singapore a big deal?
From Sex in the Tropics 2008 on the blooooooooooo blog
Coral mass spawning in Singapore was first recorded by Dr James Guest in 2002. It was the first record of coral spawning in the tropics. At least 18 different coral species from ten genera and five families (Acroporidae, Faviidae, Merulinidae, Oculinidae and Pectiniidae) have been observed to spawn in our waters! Mass spawning occurs on the third to fifth nights after the full moon between 8 and 10 p.m.In interviews with the media, Dr James Guest emphasised that corals are part of Singapore's biodiversity and natural heritage. "There are 255 species of corals recorded here, and there may be some corals here that were around before Stamford Raffles arrived."
|Our corals can be huge!|
Like this one photographed
by Toh Chay Hoon on facebook.
A beautiful series of dive clips of Singapore's wild reefs
compiled by Debby Ng.
compiled by Debby Ng.
In 2014, Minister Tan Chuan Jin joined one of the final dives to view this natural wonder and pronounced them "Absolutely magical". Thanks to Debby Ng, we get live updates of how the dive with Minister went.
photos on facebook!
As well as these interesting points provided by NParks.
General Observations on Coral Spawning
- Synchronous mass spawning (as it is called) was first observed in Singapore in 2002.
- Dr James Guest was the PhD student who studied this event, along with researchers from the Reef Ecology Study Team (NUS), headed by Prof Chou Loke Ming.
- NParks has been monitoring coral spawning together with volunteers and researchers, since 2005.
- Areas where spawning have been observed: Pulau Satumu (Raffles Lighthouse), Kusu Island, Pulau Semakau, Pulau Hantu and Labrador Nature Reserve. Spawning seems to be less intense in the other areas, but this could be due to several factors: different composition of species, less than ideal water conditions, less intense monitoring at other sites, and excessive exposure to ambient light at night.
- Mass spawning follows the lunar cycle, and occurs for 8 to even 14 days after the full moon in late March or early April, typically around Easter weekend. The peak intensity is around 3 to 5 (and possibly 6) days after the full moon. However, we have only observed the spawning from the 1st to the 8th night after the full moon in Singapore so we cannot say for sure if our corals spawn continue to spawn beyond the observed period.
- Up to 35 species have been documented to participate in the mass spawning event in any one year since we started to monitor the spawning in 2002. This was recorded in 2010.
- Not all coral species participate in mass spawning events – other species follow different spawning strategies including several (or even monthly) spawning events throughout the year while others are brooders, where fertilization occurs internally and they “brood” their eggs and release mobile larvae. Mass spawning is just the most noteworthy of such events.
Observations on the 2014 Mass Coral Spawning Event
- The spawning was predicted to occur following the April full moon, and following previous spawning observations in Singapore, we predicted that the peak spawning will occur from the 3rd to 5th night after the April 15th full moon. The corals are likely to continue spawning for several more nights, but the spawning is likely to be sporadic and not as intense.
- A total of 28 (and possibly 30 or more) hard coral species from 18 (or more) genera spawned over the three nights between 7pm and 10pm, along a 100m stretch of reef along Pulau Satumu, where Raffles Lighthouse is located.
- There were some observed variations in spawning intensities between species or group of species.
- The spawning intensity was generally high and comparable to the observations in 2004, 2005, 2008 and 2010 for three dominant massive or boulder coral species, where egg-sperm bundles were released from almost the entire colony surfaces.
- However, three plate coral species did not show an intense a spawning as previous events, with only part of the colony spawning.
- There was one new spawning records in 2014 which was not recorded previously.
- We are also aware that NOAA (National Oceanographic and Atmospheric Agency) from the US has indicated a 50% chance of an El Nino event this year. The last one was in 2010, which was followed by a La Nina event can causing worldwide mass coral bleaching which devastated many reefs in the region. The corals in Singapore recovered well from that event, but we are still concerned about the potential of another bleaching event this year and are monitoring the situation closely.
Here's a video of the 2014 coral spawning
shared by Jeffrey Low on flickr
shared by Jeffrey Low on flickr
MORE Photos and stories of mass coral spawning in 2014
- Coral Spawning & Marine Life@Raffles Lighthouse@Pulau Satumu by Tan Chuan Jin on facebook
- Corals Spawning in Singapore! on the Hantu Blog
- Coral Spawning @ Pulau Satumu - 20th April by Toh Chay Hoon on facebook
- Coral Spawning @ Pulau Satumu - 19th April 2014 by Toh Chay Hoon on facebook
- A spawn of articles on coral spawning in Singapore! Jul 2012
- Orgy in the Sea: Mass coral spawning 2012!
- Sex in the Sea: Singapore style Mar 2010
- Spawn of coral on video! Apr 2010
- Pop pop pop - Coral babies in the making Apr 2011 by Neo Mei Lin
- SECORE Workshop - Coral spawning in Singapore (1-2 April 2010) by Neo Mei LinOrgy on Singapore Reefs: coral mass spawning Apr 2010
- Sex in the Tropics 2008 on the blooooooooooo blog
- Spawning 2007 part 1 and part 2 by Leong Wai
- 2006 mass spawning event photos by Jani
- 2005 mass spawning event photos by Jani
- 'Tis the season for coral spawning by Chang Ai-Lien Straits Times 9 Apr 2002