WILLEMSTAD – Last week, another coral rearing program was hosted at the CARMABI Foundation in Piscadera, organized by SECORE International in collaboration with local foundations REACT and Reef Renewal Foundation Curaçao, The DiveShop, and CARMABI itself. This partnership provided local youth, NGOs, and participants from the Bahamas, Bonaire, St. Croix/USVI, Colombia, Trinidad & Tobago, and Honduras with the opportunity to learn about coral larvae cultivation techniques developed in Curaçao by SECORE and CARMABI, and how these techniques can be used for research and coral reef restoration.
From May 19 to May 29, SECORE International — an American organization dedicated to developing new coral restoration techniques worldwide — hosted a workshop at CARMABI, offering participants in-depth training on the latest techniques and possibilities in this field. Ten participants from six Caribbean countries traveled to Curaçao for the workshop, and more than 20 local youths joined parts of the program through Carmabi’s Marine Youth Rangers Program.
Although most coral species reproduce massively in the fall during the so-called "coral spawning," there is one species of brain coral (Diploria labyrinthiformes) that reproduces for several months starting in May. During spawning, colonies of this species release bundles containing both eggs and sperm. When these bundles break apart, eggs and sperm from different colonies can fertilize, forming coral larvae that can settle on the reef floor after a few days. By collecting these bundles at four coastal sites using special nets, CARMABI’s lab successfully cultivated 250,000 coral larvae. These will eventually be outplanted on the reef using specially designed settlement tiles developed by SECORE.
During the workshop, SECORE provided lectures and field trips showcasing modern methods for effectively cultivating coral larvae. Special attention was given to new approaches that increase genetic diversity in future coral generations, improving their chances of adapting to challenges like climate change and pollution. Participants also learned about recent innovations that can increase the number of coral larvae successfully outplanted onto reefs.
The organizers were positively surprised by the large number of coral larvae that could be cultivated during the workshop. Like many other coral species, brain corals in Curaçao and throughout the Caribbean have suffered tremendously from high sea temperatures over the past two years and the outbreak of the devastating coral disease SCTLD. “Nevertheless, the surviving colonies are still capable of reproduction, which may be a sign that at least some corals are able to adapt to changing conditions,” said Dr. Valerie Chamberland of SECORE, who has worked with the organization at CARMABI for years.
At the same time, participants were introduced to the latest cryopreservation techniques by Dr. Kristen Marhaver, who has established a specialized lab at CARMABI. Through cryopreservation, eggs and sperm of endangered species, including many coral species, are stored at extremely low temperatures and can be used at a later time. By freezing this genetic material, the genetic diversity of animal populations is preserved. “Now that SCTLD seems to be declining, we can thaw the previously frozen genetic material and use it to fertilize the eggs collected during the workshop. This creates a new generation of coral larvae with enormous genetic diversity, potentially better equipped to adapt to current conditions,” explained Dr. Kristen Marhaver, who leads this program at CARMABI.
In addition to professionals interested in coral rearing techniques, more than 20 local youths actively participated in the dives to collect coral eggs and sperm, as well as in the subsequent lab work. In total, over 50 participants joined the activities, ranging from local youth to Caribbean organizations involved in reef restoration, local NGOs (REACT, Reef Renewal Foundation Curaçao), CARMABI’s educational program (NME), park rangers from the Curaçao Marine Park, and scientific researchers. All participants highly valued the diverse nature of the workshop, which brought together a wide range of international, local, young, and more experienced participants. Spending several days together allowed for meaningful exchanges on how cultivating coral larvae can contribute to reef restoration in Curaçao and other Caribbean islands.
The cultivated coral larvae are thriving. 80 percent survived the first week — significantly higher than in the wild, where the survival rate is estimated at around 1 percent. The larvae have now attached to the settlement tiles and will soon be outplanted onto the reef to continue their growth.
Press Release: Many and Diverse Groups Participate in Successful Coral Rearing Program