CRF™ CORALS SPAWN IN THE WILD AND NURSERIES MULTIPLE NIGHTS IN A ROW
Coral Restoration Foundation™ nurseries and restoration sites are living laboratories for coral research, and this year during the annual Acroporid coral spawn our “lab” was open for business. The CRF™ science team spent weeks preparing for this annual natural phenomenon, coordinating dive teams and dive boats, constructing gamete collection nets, and organizing potential gamete transfers with NOAA and SEZARC researchers. And, finally, this week, this hard work paid off: We witnessed our corals spawn both in our nurseries and at our restoration sites in the wild!
CRF™ divers prepare "spawning alley" in one of our nurseries; tenting each colony to collect gametes. ©Alexander Neufeld Photo/Coral Restoration Foundation™
On Saturday August 13th, a team of five CRF™ divers led by our Photomosaic and Technology Coordinator, Alexander Neufeld, jumped into the water at North Dry Rocks reef, one of our most successful restoration sites home to both staghorn and elkhorn colonies outplanted as early as 2014! Our team was immediately optimistic that spawning would occur because the entire reef was covered in active wildlife ready to feast on fatty coral gametes.
Our mission at North Dry Rocks was to document the timing of the coral spawn to inform future predictions. We were sharing the area with researchers from NOAA whom we had been in communication with to ensure a smooth and cooperative night on the reef. NOAA placed gamete collection tents over our outplanted colonies. When the big moment finally occurred around 10:15pm the entire water column came to life! Millions of tiny floating gamete bundles filled the sea, and the NOAA spawning nets, and collection tubes filled to the brim. Our team frantically recorded colony genotypes, the start time of spawning and the duration, all while fighting the urge to dance with excitement underwater.
Staghorn and elkhorn coral colonies outplanted by CRF™ on North Dry Rocks Reef spawn and their gametes are collected by NOAA scientists. ©Alexander Neufeld Photo/Coral Restoration Foundation™
A bit of background on the biology of corals will help explain why this event is so important for CRF™ and coral scientists around the world. Corals naturally reproduce two ways, sexually and asexually. CRF™ propagates corals asexually by fragmenting large colonies into smaller clones and allowing them to regrow. These corals will be genetically identical to their parents. But corals also reproduce sexually, by spawning. During spawning events, corals of the same species simultaneously release their gametes (sperm and eggs) into the water column. The sperm and eggs from genetically different corals combine, resulting in a genetically unique coral baby, just like humans!
Staghorn coral gametes are set to spawn from their parent colony living in a CRF™ nursery and collected in test tubes! ©Gabriel Jensen/Coral Restoration Foundation™
Genetic recombination from sexual reproduction has built diverse gene pools over millions of years. Diverse ecosystems are resilient in the face of multiple threats. The more genotypes that exist on the reef the more opportunity there is for coral communities to survive different
mortality events. Restored corals spawning on the reef is the first step to jumpstarting natural recovery and maintaining a genetically diverse ecosystem! As we continue to restore and conserve these pockets of biodiversity, they will act as steppingstones for ecosystem wide recovery, seeding Florida's Coral Reef with new life!
Meanwhile over in one of our Coral Tree™ Nurseries another group of divers led by our Science Program Manager Amelia Moura was watching the carefully selected corals in our spawning alley. Prior to this predicted spawning week Amelia and some of our staff selected a variety of staghorn genotypes from our gene bank to be placed in a specific area of our open-ocean nursery we call "spawning alley". This selection ensures we are gathering gametes from a variety of genotypes and accurately monitoring the spawning of each without having to swim through 500 Coral Trees™. The spawning in our nursery was slightly less intense on Saturday but our collaborators at SEZARC still managed to cryopreserve multiple genotypes of coral gametes from our colonies which they will use in future genetic research.
Spawning alley is set up with gamete collection nets in the CRF™ Tavernier Coral Nursery ©Alexander Neufeld Photo/Coral Restoration Foundation™
Saturday night was the first of three observed nights of spawning. Using evidence from previous spawning observations our Science Team knew it was likely the corals would spawn more than once and so on Sunday and Monday nights boats filled with hopeful CRF™ divers monitored our restoration and nursery sites. By Monday night the reef had completed its spawning and we did not observe the release of any more gametes, but our nursery was highly active with over 50% of our Coral Trees™ releasing eggs and sperm! Our teams will be heading out once more to our Coral Nursery tonight (Tuesday August 16th) to record any spawning activity which will help inform future spawning predictions. Overall, our entire CRF™ team is overjoyed to have witnessed another spawning successful season and we are looking forward to the research and progress for reef restoration that comes from our scientific collaborations.
Elkhorn corals outplanted by CRF™ on North Dry Rocks Reef spawn on Saturday August 13th ©Alexander Neufeld Photo/Coral Restoration Foundation™
Coral Chronicles Editor
Madalen Howard is CRF's Communications and Outreach Coordinator. Madalen comes to CRF™ via a winding road from the Tennessee hills, to the South Carolina low country, ending here in Florida’s Coral Reef. She earned her Bachelor's degree in Marine Biology and a Minor in Environmental Studies from the College of Charleston in 2016. Her experience ranges from field research to education, marketing and digital communications.
With CRF™ Madalen creates inclusive pathways to scientific discovery through content creation and by building and fostering relationships with press, digital media creators, and local community members. Throughout her life Madalen has had a skill connecting people with nature, and is excited to bring people into the world of coral restoration.