Facilitating the facilitators: Advancing coral reef restoration by considering ecological keystone species

Summary

Coral reefs are degrading rapidly and new conservation tools such as restoration are deemed necessary to save this valuable ecosystem. Coral gardening is a commonly-applied restoration technique where corals are first nursery-grown and then outplanted onto degraded or artificial reefs to assist ecosystem recovery. However, the effectiveness of coral gardening is debated, because these restoration efforts have generally been costly and hampered by ecological setbacks.

Inspired by healthy reefs, this thesis aimed to use ecological knowledge to improve coral gardening techniques. Through large-scale field experiments in Kenya, the dynamics of herbivorous and coral-predating keystone species were characterized and possibilities to use this ecological information to improve coral gardening were explored. Several opportunities were identified, including facilitating herbivorous fish through nursery site selection and preventing coral predation through artificial reef design. Applying these insights increases the cost-effectiveness of coral gardening and makes restoration a more viable coral reef conservation approach, as illustrated by the successful restoration project in Kenya