#coral spawning

coral babies

Scientists in Australia have achieved the first-ever offseason coral spawning in the history of coral breeding and restoration sciences.

Excerpt from this story from EcoWatch:

The news is full of dire warnings about the future and current health of the Great Barrier Reef, but the World Heritage Site is not dead yet.

Scientists on Tuesday night recorded videos of corals spawning en masse off the coast of Cairns, Queensland.

"Nothing makes people happier than new life, and coral spawning is the world's biggest proof of that," Reef Teach principal marine scientist Gareth Phillips said in a statement emailed to EcoWatch.

Coral spawning is one way in which corals reproduce. During most of the year, the jellyfish-like animals reproduce asexually. But, once every year, they send tiny balls containing sperm and eggs up into the water. These balls break apart, the sperm and eggs bump into each other and new coral babies are born.

Phillips has spent the past 10 years watching coral spawning, which typically occurs at night when there are fewer predators. This year, billions of babies were born, and the display was uniquely impressive.

"I've seen the corals all go off at once, but this time there seemed to be different species spawning in waves, one after the other. The conditions were magical with the water like glass and beautiful light coming from the moon," he said.

Phillips said he first observed Acropora, or branching corals, release pink-mauve balls and then Porites, or boulder corals, releasing what looked like a plume from a flooding river.

The millions of new coral babies are good news for the reef after a difficult few years. The climate crisis has had a severe impact on the 2,600 kilometers (approximately 1,616 miles) of coral as warmer than usual ocean temperatures encourage coral bleaching, when the coral expel the algae that give them both nutrients and color. The reef suffered back-to-back mass bleaching events in 2016 and 2017, and again in 2020. A recent study found that the five mass bleaching events since 1998 had left only two percent of the reef unscathed.

Corals are stationary animals that build hard skeletons to protect their colonies. So how do they reproduce and ensure the genetic diversity of future generations? 

Earlier this month, the reef-building corals of Flower Garden Banks National Marine Sanctuary spawned, releasing reproductive material into the water column where it has the opportunity to mix and produce larvae. Those larvae will drift along in the ocean until they find a suitable place to settle, and there they'll grow into a new generation of corals! 

(Photo: Emma Hickerson/NOAA) 

On the Fringe in Australia

By Linda Tancs Located in Western Australia’s Gascoyne region (the Coral Coast), Ningaloo Reef is the largest fringing coral reef in the world at 186 miles. Just footsteps from the shore, the shining turquoise waters beckon any time of year, but especially now. That’s because between seven and 10 days following the full moon in March and April, a spectacular coral spawning event takes place,…