Throughout the first week of August, 12 organizations came together in an unprecedented collaborative effort to protect the future of Florida's Coral Reef during one of nature's most elusive events, coral spawning. Scientists across the organizations worked tirelessly to propagate and conserve the next generation of corals by collecting eggs and sperm (gametes), strategically fertilizing embryos, and cryopreserving sperm to safeguard invaluable genetic diversity for generations to come.
Coral spawning is exceedingly rare, occurring once a year and within a narrow window dependent on lunar cues and environmental conditions. Just after 10:00 pm, corals begin synchronized breeding, releasing millions of egg and sperm bundles simultaneously. The bundles must encounter other bundles of the same species for fertilization to occur. But after decades of decline, coral colonies have become so sparse and widely dispersed that the bundles often cannot find one another in the water, making natural reproduction increasingly difficult and leaving some species functionally extinct in Florida. Now, fewer than 150 unique elkhorn corals and 300 staghorn corals remain on Florida's Coral Reef—just 1% of their former abundance . But scientists are not giving up.
Funded through a four-year NOAA grant spearheaded by the University of Miami Rosenstiel School of Marine, Atmospheric, and Earth Science, the Re5 (Resilient Reef Research, Rescue and Restoration) initiative, the organizations devised a plan. Dive teams collected millions of gametes from elkhorn and staghorn corals at offshore nurseries operated by Reef Renewal USA and Mote Marine Laboratory near Key Largo. The gametes were then rapidly transported to a temporary laboratory at John Pennekamp Coral Reef State Park through a partnership with Mote Marine Laboratory , where experts across organizations determined desirable genetic crosses in order to create fertilized embryos that would prove most resilient to environmental stressors. Concurrently, another team worked to cryopreserve additional sperm for future restoration purposes.
"This project aims to incorporate new innovative approaches into coral restoration while also bringing together many years of experience of coral spawning that is dispersed across several institutions working on Florida's Coral Reef," said Andrew Baker, Principal Investigator of the grant and a Professor in the Department of Marine Biology and Ecology at the University of Miami Rosenstiel School. "Our reef is in trouble and we need to take urgent action to scale up efforts to help restore and rebuild one of the state's most valuable environmental and economic resources."
Throughout seven days, scientists observed 25 elkhorn genotypes and 36 staghorn genotypes spawning, resulting in 116 unique, directional crosses using assisted fertilization. The scientists ultimately produced more than 1,500,000 total embryos resulting in over 61,000 elkhorn larvae and 47,000 staghorn larvae divided between The University of Miami Rosenstiel School, Mote Marine Laboratory, The Florida Aquarium, The Reef Institute, and The Smithsonian Marine Station. The organizations will continue nurturing and growing the larvae, and within two years, return the new corals to the same nurseries before finding a permanent home on reef sites nearby, including Mission: Iconic Reefs locations in the Florida Keys National Marine Sanctuary and the Kristen Jacobs Coral Aquatic Preserve.
CLICK HERE TO DOWNLOAD BROADCAST-QUALITY VIDEO & PHOTOS OF THE CORAL SPAWNING
"What we have done over a few weeks would have never happened without human intervention," said Celia Leto, Senior Biologist and Manager of the Coral Reproduction Laboratory at Mote Marine Laboratory. "The sheer number of gametes collected and larvae produced is a testament to the preparation, expertise, and collaboration of everyone involved. It was amazing to see all of the partners come together for this effort and make this remarkable achievement possible."
Participating partners included the University of Miami Rosenstiel School, Reef Renewal USA, Mote Marine Laboratory, The Florida Aquarium, The Reef Institute, SECORE International, Phillip and Patricia Frost Museum of Science, Nova Southeastern University, Smithsonian Marine Station, John Pennekamp Coral Reef State Park, Biscayne National Park, and AECOM.
"Collaboration allows us to push the boundaries of what is possible in coral restoration," said Keri O'Neil, Director and Senior Scientist of the Coral Conservation Program at The Florida Aquarium. "This effort brought together people from across the coral restoration community to seize a rare opportunity and turn it into something with tremendous potential for the future of Florida's Coral Reef."
All work was conducted under permits issued from the Office of National Marine Sanctuaries.
