It’s that time of year when corals take advantage of the full moon, dust off the old Barry White records and get down and dirty to bring new life to the Great Barrier Reef (the Reef). 

During this dazzling display of synchronised mass reproduction, corals release millions of bundles of sperm and eggs into the ocean in a kaleidoscope of colour, bringing their next generation to life.

But it turns out corals are not the only ones getting jiggy on the Reef during the annual spawning.

Reef Authority Chief Scientist Dr Roger Beeden said an array of marine species also spawn alongside the corals.

“It’s one of nature’s most remarkable reproductive spectacles, with invertebrates and sponges often spawning at the same time as the coral.  This phenomenon showcases the resilience and regeneration of the Reef ecosystems,” Dr Beeden said.

“We’ve known about mass coral spawning for more than 40 years, but we’re only now discovering all these other marine species are taking advantage of the coral spawning cover to have a little fun of their own.

“It’s a safety in numbers approach. Clams, sponges, sea cucumbers and starfish, among others, are using the protection of this unique breeding opportunity to release their spawn and create their next generations,” Dr Beeden said.

The magical event happens after a full moon, and only when water temperatures can stimulate the maturation of reproductive cells within adult corals.

It can last anywhere from a few days to a week, and while spawning takes place on a large scale it doesn’t happen across the Reef all at once, with location also a factor. 

Corals on inshore Reefs usually spawn after the first full moon in October, while those on outer reefs tend to spawn during November and even December.

Dr Beeden said the mass spawning is more than just an amazing sight, it’s a critical time for Reef renewal, particularly given the increase in mass coral bleaching events over the past decade and the forecasts of another hot summer.

“Coral spawning is an incredibly important part of the natural recovery process. There is no more important event for the future of the Reef than the maturation of reproductive cells within adult coral,” Dr Beeden said.

“These spawning corals are genetic gold for Reef resilience. Corals that have survived coral bleaching events may pass on more heat tolerant genes to the next generation enhancing the adaptation of coral communities and long-term survival of the Reef.”

Coral spawning is a time of new life and hope — a time to renew our commitment to taking small steps every day to reduce the impact of climate change, helping ensure the health of the Reef, both now and into the future.