Different levels of Coral Bleaching/Threats

Coral bleaching is a process which causes loss of vivid colours from coral organisms & turns them white due to expulsion of symbiotic zooxathellae algae.

Clive Wilkinson of the Global Coral Reef Monitoring Network (GCRMN) of Townsville (Australia) identified four overlapping levels of coral bleaching –

i.Catastrophic Bleaching: Adversely affecting 95% of shallow water corals in Baharain, the Maldives, Sri Lanka, Singapore & Tanzania.

ii.Severe Bleaching: Accounting for 50-70% death of corals in Kenya, Seychelles, Japan, Thailand & Vietnam.

iii.Moderate Bleaching: Resulting into 20-50% coral mortality but with quick recovery.

iv.Insignificant Bleaching(No Bleaching): If bleached, percentage remained below 20% of coral death.

Threats of Coral Reef

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