As a coral reef manager, it is helpful to understand important indicators that support coral reef resilience. Resilience is more than resisting or being able to recover from a major disturbance, such as surviving bleaching, or resisting bleaching. For a community to be resilient, it must also be able to continue to thrive, reproduce, and compete for space and resources. For example, some coral communities that have bleached may not have experienced mortality, but may be weakened and less able to thrive, grow, and reproduce in the competitive reef environment. Multiple indicators contribute to resilient coral communities, some of them well known and others to be discovered. Scientists are working to identify important indicators that managers can evaluate to assess the resilience of a coral community. Some indicators of a healthy and resilient coral reef include:
- Strong coral recruitment — Indicates strong connectivity to healthy source reefs (although the reef may be self-seeding) and good conditions for larval settlement and growth (available substrate, good water quality).
- Low human impacts — Indicates a lower level of local stressors that weaken the ‘immune system’ of coral reefs; low human impacts may mean corals will be able to resist and recover from major stress events more effectively.
- Healthy herbivore populations — Indicates a high potential for coral reefs to recover from major stress events as herbivores graze down algae and thus prepare the substrate for larval settlement, which supports coral reef recovery following disturbance.
For more information, see the Monitoring and Assessment section, and check out recent research highlighting fundamental differences in the recovery and state of Caribbean versus Indo-Pacific reefs, including indicators that might predispose the Caribbean to lower resilience. ref