Unusually warm water is a major cause of widespread bleaching, though other stresses can contribute. A coral that loses its helpful algae loses an important energy supply. If conditions improve in time, the partnership may recover. White colour alone does not tell us that every coral is already dead.
Water and oceans · Discover & try
Can a bleached coral still be alive?
Reading level 2 of 5 · DevelopingChange
Word help
Symbiosis
A close biological relationship between different organisms.
Bleaching
Loss of symbiotic algae or their pigments from coral tissue.
Mortality
Death, which is not identical to bleaching.
Watch · Try · Explain
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Conceptual partnership and stress sequence; stage timing and recovery are not predictions for a real reef.
What to look for
- Distinguish algae loss from tissue death.
- Compare persistent stress with relief.
- Notice that progress is not a count of days.
Explain what you noticed
A different reef survey sees pale coral tissue but has not checked whether it is living. Which conclusion is justified?
Keep this idea: Bleaching is loss of symbiotic algae or their pigments; a bleached coral is vulnerable but not necessarily dead.
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Source material checked 2026-10-28. Explanations and activities by Nepedia. Source links do not imply endorsement.
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