Coral Spawning
CREATING THE CORALS OF TOMORROW
Corals are living animals and, like many other species, they reproduce sexually. Sexual reproduction is crucial for increasing genetic diversity, helping coral populations adapt to environmental changes.
SYNCHRONIZED SPAWNING
During coral spawning events, corals release eggs and sperm into the water in a synchronized display that often occurs around a full moon. Some corals, like Acroporids, are hermaphroditic and release both eggs and sperm, while others are either male or female, releasing only one type of gamete.
The timing and frequency of coral spawning can vary across species and regions, but these events typically occur in late summer. This natural phenomenon is vital for replenishing coral populations and sustaining the biodiversity of reef ecosystems.
Evidence of healthy corals
More than 15 years ago, in a historic first, corals CRF returned to the “Wellwood Site” on Molasses Reef became the world’s first outplanted corals documented to spawn. Since then, we have recorded spawning at multiple restoration sites – strong evidence that our methods are working; spawning is an energy intensive activity and seeing this sexual reproduction indicates that our corals are happy and healthy.
SUPPORTING THE SCIENCE
The broodstock corals in our nursery also spawn every year. By carefully monitoring our corals, we determine gamete maturity, which helps us to predict when spawning will occur. As a result, our infrastructure, corals, and the data we have available — including comprehensive genetic information — provide a unique resource for researchers from around the world looking to study this extraordinary event.
Spawning Observation & Gamete Collection
Coral Restoration Foundation has played a critical role in observing coral spawning and facilitating gamete collection events across Florida’s reefs, with a particular focus on Acropora cervicornis and A. palmata species.
Cryopreservation & Genetic Diversity
CRF has been at the forefront of coral cryopreservation efforts, collaborating with partners like SEZARC and Florida Aquarium, providing gametes of known genotypes to their programs. This work is helping to bank critical genetic diversity for future generations.
Institutional Collaboration
CRF’s efforts have consistently involved collaboration with top research institutions. These collaborations have led to advancements in cross-fertilization techniques, creation of new genotypes, and outplanting of sexually reproduced coral larvae.
Applied Research
CRF is committed to applied research that boosts reef restoration efficacy. Our involvement in breeding efforts supports the ecological resilience of coral populations, and our partnerships have facilitated numerous advancements in coral reproduction and restoration science.
Case Study: Boosting Genetic Diversity with Florida Aquarium
A highlight of Coral Restoration Foundation’s collaborative efforts is our ongoing collaboration with Florida Aquarium, with a focus on coral gamete collection, fertilization, and outplanting.
In 2018, scientists from Florida Aquarium collected gametes from CRF corals during spawning events and manually mixed them to assist with fertilization. These fertilized gametes were then settled and nurtured in the ex-situ tanks at Florida Aquarium, where they were carefully monitored and raised into more than 3,000 young coral recruits. Once these corals reached a suitable size, they were transferred back to CRF’s in-situ coral nurseries. After thriving in the ocean-based nursery environment, around 1,500 of these new coral genets were rehomed on Florida’s reefs, contributing to the restoration of genetic diversity and ecological resilience in Florida’s coral populations.
In 2024, despite the stress of the Fourth Global Bleaching event, one of these genotypes was observed spawning in the CRF Tavernier Coral Tree Nursery.
This project exemplifies the power of partnerships in advancing coral restoration techniques, offering a promising future for coral reefs by combining the strengths of both ex-situ and in-situ restoration practices.