Did you know that corals can have babies? They do it in a spectacular underwater event known as “spawning.” In an exciting new initiative, Nature Seychelles is gearing up to harness this natural occurrence by launching a ground-breaking coral breeding lab on Praslin Island, Seychelles, thanks to a partnership with CANON and the UK-based Coral Spawning Lab.
Coral reefs are bustling ecosystems that provide crucial services. Sadly, climate change has wreaked havoc on these reefs, with coral bleaching events happening more frequently. 2024 witnessed the fourth mass coral bleaching event, which is still ongoing.
Reefs are nearing a tipping point, making natural recovery increasingly tough, if not impossible. If we keep losing these vital ecosystems, we’ll also lose the essential services they provide. That’s where active restoration comes in.
For the past 15 years, Nature Seychelles has been restoring coral reefs in Cousin Island Special Reserve affected by bleaching, using underwater rope nurseries to cultivate thousands of coral fragments before outplanting them onto damaged reefs.
Helping corals grow faster
Now, restoration efforts have shifted to the newly launched ARC Facility, a land-based coral aquaculture facility funded by the Adaptation Fund, CMA CGM, and SeyCCAT. This facility uses a technique called micro-fragmentation, which involves breaking coral fragments into thousands of tiny pieces. These micro-fragments are nurtured in controlled tanks until they’re ready to be returned to the reef. This method allows for a high volume of coral production from just a few small pieces, promotes faster growth, and supports various coral types, including the slow-growing massive reef builders. However, it does have its limitations when it comes to genetic diversity, which is where coral spawning becomes essential.
So, what exactly is coral spawning?
They might look like rocks or plants, but corals are made up of tiny animals known as “polyps.” Most of the reef-building corals create their structures from calcium carbonate, which builds up over time to form the impressive coral formations we see. Within their tissues, corals host tiny algae known as zooxanthellae, which provide food through photosynthesis. This special relationship is what allows them to flourish.
Corals have two main ways of reproducing. A piece can break off and start a new colony, or an existing colony can grow larger by budding off new polyps. Breaking can happen after a storm or due to grazing animals. If the broken fragment lands in a suitable spot and attaches, it can develop into a new, genetically identical colony. Existing colonies expand by adding new polyps through a process called budding. Coral reef restoration projects largely used coral fragments.
Coral gametes (Photo credit: Coral Spawning Lab)
Corals also reproduce by releasing reproductive cells called “gametes” into the water. These gametes come together to form a unique coral larva, which can eventually settle on a surface and grow into a new coral. This whole process is referred to as “coral spawning.”
Coral spawning is often likened to an “underwater snowstorm.” Throughout the reefs, corals release tiny bundles of reproductive cells into the water, resembling colourful beads that gently float upwards. This event is timed, occurring only a few nights each year and is closely tied to the lunar cycle. Spawning is crucial as it promotes genetic diversity, resilience, and adaptation to the warming oceans.
So, what’s the purpose of the coral spawning lab?
This facility is being crafted to replicate this incredible event indoors. Think of it as a high-tech “maternity ward” for corals.
“The coral spawning lab is being built primarily to facilitate this type of coral reproduction in a controlled environment and to produce genetically diverse coral offspring,” says Dr Nirmal Shah, Nature Seychelles’ Chief Executive. “It will address the challenges of natural spawning events in Seychelles, which are largely unknown. The process is new to us. We will conduct training and scientific research, using imaging to document the process and for education and awareness.”