When corals are stressed, they produce a layer of mucus that covers their surface. This mucus helps to protect the coral from temperature fluctuations, UV radiation, and pollutants. It also traps food particles and provides a habitat for beneficial bacteria.

2. Symbiosis with zooxanthellae

Zooxanthellae are single-celled algae that live in mutualistic symbiosis with corals. They provide the coral with food through photosynthesis, and in return, the coral provides them with a protected environment. When corals are stressed, they may expel their zooxanthellae, which causes them to bleach. However, corals may be able to recover if the stress is not too severe.

3. Calcification

Corals build their skeletons by depositing calcium carbonate. This process is called calcification. When corals are stressed, they may reduce their rate of calcification or even stop calcifying completely. This can make them more susceptible to damage and disease.

4. Recruitment

Recruitment is the process by which new corals settle and grow. When corals are stressed, they may produce fewer larvae or the larvae may be less likely to survive. This can make it difficult for coral populations to recover from damage or disease.

5. Regeneration

Corals have a remarkable ability to regenerate. When they are damaged, they can grow new tissue and repair their skeletons. This process is essential for coral survival.

6. Adaptation

Corals are able to adapt to their environment over time. They may develop new resistance to stress factors, such as higher temperatures or pollution. This can help them to survive in changing conditions.

7. Resilience

Coral reefs are highly resilient ecosystems. They are able to recover from damage and disease, and they can adapt to changing conditions. This resilience is essential for the survival of coral reefs in a changing world.