In a remarkable advancement for coral conservation, Mote Marine Laboratory has successfully achieved the spawning of Eusmilia fastigiata, commonly known as smooth flower coral, with parent colonies settled just 22 months prior under managed care.
The original corals were received in March 2022 as part of the Florida Reef Tract Rescue Project (FRTRP), an Association of Zoos and Aquariums member-driven coral rescue and conservation network focused on the rescue, housing, and future propagation of Florida corals affected by stony coral tissue loss disease (SCTLD). The corals received from the FRTRP spawned, and Mote’s International Coral Gene Bank successfully settled them. Over the last two years, the Gene Bank has raised the coral and facilitated the spawning of a second generation. The selective nature for the settlement of this species and the specific conditions required to promote sexual reproduction make the successful production of this second generation under managed care conditions a notable challenge. The feat underscores the species’ ability to be sexually propagated within a controlled environment.
The Gene Bank, located at the Mote Aquaculture Research Park (MAP) in eastern Sarasota County, serves Mote’s mission to protect and restore coral reefs. It acts as a sanctuary for corals from Florida’s Coral Reef and other Caribbean regions, with future plans for expansion into the Indo-Pacific. The Gene Bank houses thousands of coral genotypes (genetic varieties) of at least 26 species stored in triplicate, offering a critical safeguard against the loss of coral genetic diversity.
Smooth flower coral is also highly susceptible to SCTLD, making Mote’s success in breeding it a significant win for coral conservation efforts. To date, this species has not been heavily utilized for active coral restoration efforts, but the ability to reproduce within a relatively young age may change this paradigm.
Smooth flower coral, however, remains notoriously difficult to settle. To encourage settlement, conditioned plugs are used and coated with bacterial films and a specific type of algae called crustose coralline. The species’ highly selective nature and the specific conditions required for settlement result in particularly low success rates. This makes the Gene Bank’s recent feat all the more significant.
The achievement of settling second-generation smooth flower coral within managed care holds immense potential for advancing coral research and restoration efforts as it has demonstrated the ability to reach reproductive maturity at a significantly smaller size and much younger age compared to most other coral species commonly used for restoration. While many boulder coral species found in Florida may require over ten years to grow large enough to spawn, smooth flower coral has shown the remarkable ability to spawn within just two years. This accelerated reproductive cycle is potentially crucial in the face of rapidly changing environmental conditions, such as rising ocean temperatures and increasing disease prevalence, as it may promote faster rates of adaptation through time. The ability to adapt to these changing conditions will be vital as coral reefs face ongoing degradation worldwide. Additionally, by incorporating smooth flower coral into restoration programs, scientists can enhance the community diversity and resilience of reef ecosystems, thereby improving the long-term efficacy of reef recovery.
“Given the increasingly stressful conditions on Florida’s Coral Reef, it is imperative that we successfully care for corals within a safe haven such as the Gene Bank,” said Dr. Erinn Muller, Director of Mote’s International Coral Gene Bank and Associate Vice President for Research. “The limited natural recruitment we see on the reef also emphasizes the need to produce corals through assisted sexual reproduction efforts within managed care. The fact that we can create multiple generations of smooth flower coral within such a short period of time provides another novel avenue to utilize for coral conservation and restoration efforts.”
Mote scientists emphasize the urgency of their work, as over the past 50 years, more than 90% of the coral cover on Florida’s Coral Reef has been lost. The Gene Bank’s meticulously designed recirculating holding systems, monitored and supported by advanced technology, create an optimal environment for corals to thrive and ensure their genetic diversity is preserved for current conservation and future restoration efforts.
“Anytime we can successfully reproduce corals that are susceptible to SCTLD, it’s a significant step forward,” said Cody Engelsma, Coral Reproduction Senior Biologist at the Gene Bank. “The fact that we have 11 out of approximately 45 corals that we settled only 22 months ago showing eggs or larvae in their tentacles is a strong indicator of the health and viability of these individuals. This achievement not only contributes to our understanding of coral reproduction but also offers hope for the future of coral reefs under threat.”
Mote Marine Laboratory remains committed to advancing the science of coral restoration and conservation through cutting-edge research and innovative techniques. The successful creation of second-generation smooth flower coral in under two years marks a critical step in the ongoing battle to protect and restore Florida’s Coral Reef.