CORAL REEFS

Corals:

• Corals are animals which live in a symbiotic relationship with microscopic algae called zooxanthellae (which live within the coral tissue).
  
  
• The zooxanthellae convert sunlight into food, providing corals with up to 90 per cent of their energy needs. They also give corals much of their colour.
  
  

Coral bleaching:

• Bleaching occurs when stressful conditions, such as heat, cause this relationship to break down, resulting in the corals expelling their zooxanthellae. This leaves the coral tissue mostly transparent, revealing the coral's bright white skeleton.
  
  
• This loss of their symbiotic algae means bleached corals are essentially starving.