Coral bleaching and reef resilience


Climate change is now recognized as one of the greatest threats to coral reefs worldwide. While a changing climate brings many challenges to coral reefs, one of the most serious and immediate threats is from mass coral bleaching associated with increasing sea temperatures.

Corals bleach when stressed – the symbiotic algae living inside coral tissues are expelled, so the white skeleton becomes visible, and in this weakened condition they may succumb to other threats, and/or to the high temperatures.

Resilience is a concept that can be applied to an ecosystem, species or even a social system, and relates to the degree to which the system can a) maintain its key functions when exposed to a disturbance, b) return to its prior state. Thus a resilient system can rebound from even major disturbances.

Three key aspects are important – the exposure to disturbance (e.g. the temperature of the sea), the sensitivity of the system to that exposure (e.g. the bleaching response of individual coral species) and finally the adaptive capacity or potential for recovery.

Management can address any of these components of resilience, though to differing degrees. The research and projects undertaken by CORDIO on coral bleaching and reef resilience all have an eventual goal to assist in managing reefs in the face of coral bleaching and climate change.

See the various aspects of our work on coral bleaching and reef resilience in the links below.

Reef resilience assessment and research

Coral bleaching forecast/alert for the Indian Ocean

Education videos on coral reefs

Normal reef

Acropora-dominated reef

Bleached corals


Degraded/algae-dominated reef

Algae-dominated reef