Pulau Hantu - A celebration of marine life

Secret lives and secret worlds hidden in Singapore's most popular coral reef.

Wednesday, September 14, 2005

Bleaching at Kusu, Permalang

Bleaching of hard corals has been spotted at Kusu Island and Permalang Reef recently. If you have seen bleaching occuring anywhere else at the Southern Islands, please send any of the following information you might have to conserve@bluewatervolunteers.org:
1. Location of reef (Reef name or location in relation to nearest island),
2. Date,
3. % of the colony bleached,
4. % of the reef bleached,
5. If possible, the species of coral bleached,
6. Photos.

Thank you!!

What is bleaching?
Bleaching occurs when hard corals (or anemones, or soft corals, etc) eject their symbiotic algae (the zooxanthellae) from their tissues, leaving them almost colourless. Bleached hard corals look white as you can see the underlying skeleton through the coral tissues. Bleached corals are NOT dead, if you look closely you should be able to see the coral polyps.

What causes bleaching? Will the corals die?
We don't really know the exact causes of bleaching, but it has been correlated with raised seawater temperatures and other environmental stresses. If the stresses are removed, corals can recover and regain their colours, if left bleached for too long, they might starve and die off.