What is coral spawning? 
Coral spawning refers to the annual reproductive event, when multiple species of corals release their eggs and sperm bundles simultaneously, creating a spectacular underwater display.

When do corals spawn? 
Coral spawning typically occurs one to six nights after the October, November and December full moons, with many corals relying on the moon's light and gravitational pull to time their spawning.

What’s coral spawn made of? 
Coral spawn are small colourful balls made up of bundles of eggs and sperm. Corals start to form these bundles about six months before they spawn. Rising water temperatures going into the summer help the eggs and sperm mature and prepare the coral for the big event.  

Why does coral spawning happen at night?
Coral spawning usually happens at night, which helps protect the vulnerable eggs and sperm from predators. Coral gametes are food for many species on the Reef including planktivorous fish and invertebrates. These species will eat every bit of plankton that comes on to a reef. Any little particle is up for grabs. So, essentially, they spawn at night when most predators are inactive.

Can I see coral spawning on the Reef?
Coral spawning is a natural event, and as a result we can’t predict the exact date and time corals will spawn. However, there are operators that conduct special Reef trips around the dates coral spawning is predicted to happen. Your best bet is to book a bespoke coral spawning trip with one of the High Standard Tourism Operators located across the Great Barrier Reef Marine Park. High Standard Tourism Operators are independently certified businesses who provide high-quality reef experiences in an ecologically way.  If you’re lucky enough to come across coral spawning while enjoying the Marine Park, please submit your sightings of coral spawning and include any images you may have via our Eye on the Reef app.

How do corals grow? 
Once fertilised, the eggs develop into tiny larvae called planulae, which float in the water for several days or weeks before settling on the reef. Once settled, a coral planula will change into a single coral polyp, bud (or divide into) other coral polyps and grow into a new coral colony. The resilience of these corals is vital for the long-term health and resilience of the Reef.