Coral bleaching

What?

"Coral bleaching is the whitening of corals, due to stress-induced expulsion or death of symbiotic unicellular algae or due to the loss of pigmentation within the algae[1]. The corals that form the structure of the great reef ecosystems of tropical seas depend on a symbiotic relationship with photosynthesizing unicellular algae called zooxanthellae that live within their tissues. Zooxanthellae give coral its coloration, depending on the particular clade. Under stress, corals may expel their zooxantheallae, which leads to a lighter or completely white appearance, hence the term "bleached"."[wikipedia.org]

"Corals rely on algae that live inside each coral polyp to provide nutrients and supplemental oxygen. Bleaching occurs when these colorful algae die out or leave the polyps, often in response to overly warm conditions. Without their brightly colored algae, the coral's skeleton becomes visible through its transparent tissue, making it appear white. Although the tissue remains intact and can recover over time, this stressful condition can cause corals to stop growing and reproducing." (Sciencedaily.com)

"Bleaching has destoyed almost 30% of the world's coral reef." (Sciencedaily.com)

Causes:

• increased in water temperature
• increased solar irradiance
• pathogen infection

"One known culprit is an ocean-dwelling bacterium, Vibrio coralliilyticus, which chokes off corals' energy supply and kills these shell-clad marine animals. At lower temperatures, the bacteria are harmless to coral. But at warmer temperatures (above 75 degrees Fahrenheit) the bacteria become virulent and can kill coral." (ScienceDaily)

Conservation action in Malaysia
Realising the incredible value of coral reefs, Department of Fisheries Malaysia have established marine parks under a government directive in 1983 to conserve and protect coral reefs for sustainable fisheries, tourism, and research. There are currently 136 marine protected areas, containing 7% of the country's coral reefs. These national parks are situated around 40 islands in Peninsular Malaysia and Sabah, which are grouped together for better management.

"Blup2 Conservation: Towards Better Ocean for Tomorrow"