Coral bleaching in the Caribbean and Indo Pacific regions is having a disastrous effect on the reefs. This is the third such event since 1997 and turns these amazing ecosystems into underwater deserts.
Bleaching occurs when coral polyps (the builders of the reefs) are stressed due to environmental changes such as increased water temperature. In these circumstances they expel tiny symbiotic algae called Zooxanthellae which live in their tissues. These algae are vital to keep the polyps alive and once expelled, the polyps die leaving tell-tale white monoliths, made of Calcium Carbonate.
Healthy coral reefs harbour a huge range of organisms and plants and can be thought of as the ‘rainforest of the seas’, their deaths cause local devastation to ecosystems as well as to human communities (by damaging tourism and fishing industries).