Identify and widen bottlenecks in the asexual restoration of endangered Orbicella boulder corals

Orbicella faveolata (OFAV) is a major reef-building coral species whose mass production has been designated as critical to restoration efforts on Florida’s Coral Reef. Success in propagating this coral has been limited and varies across nurseries making scaling up production challenging. In situ nurseries in Florida experience varying conditions affected by localized factors that can have substantial effects on fragment healing rate, growth, and survival. Therefore, we evaluated the effect of colony source location, genotype, and in situ nursery characteristics on the healing rate, growth, and survival of OFAV fragments in five in situ and ex situ nurseries (NSU, University of Miami, Mote Marine Laboratory) across Florida’s Coral Reef. 

Initial results showed differences in the condition of fragments between nurseries, nursery types, and over time. The condition of frags at all of the ex situ nurseries worsened over time indicating that mortality had not plateaued by three months after fragmentation or transfer from ex situ nursery systems into in situ coral nurseries. The Mote Islamorada and NSU ex situ nurseries had frags in the best condition after three months while UM and Mote’s IC2R3 systems had fragments in the worst condition. In situ nurseries offered better conditions than ex situ nurseries for O. faveolata. In situ frag condition improved almost immediately after transfer and they had lower mortality, less recession, and higher growth after three months.

Project onset was delayed until late February 2025 due to weather reducing the monitoring time frame and making it harder to determine significant differences between the nurseries and treatments. Sea surface temperatures exceeded the thermal thresholds delaying the collection of corals of opportunity. We intend to continue to monitor, analyze data, and investigate the differences between nursery facilities and treatments to uncover the mysterious performance of O. faveolata in coral restoration beyond the project period.