Split Shifts: Coral Spawning Take Two Is Anything But Predictable

17 December, 2019

One month after the northern sections of the Great Barrier Reef burst into a billion boulder eggs for the annual coral spawning event, sections of Reef north of Cairns last night put on an encore performance and marine scientists claim it was better than any spawning event seen in the last decade.  

Russell Hore, Quicksilver Reef Biosearch Manager, along with his colleagues, predicted that cooler water temperatures in the lead up to spawning would result in the split spawn.

“While the Agincourt Reefs experienced a coral spawning in November, we always believed that the main coral spawn would happen after the full moon in December,” said Mr Hore, a zoologist and a marine biologist who has been diving the Great Barrier Reef for almost 30 years and who also noted changes to the reef.

“In the lead up to the spawning day, the reef becomes fecund. It's almost as if you are watching a pregnancy on a minute scale – without the cravings for ice-cream. If you get up close, you will see little orange balls of eggs pushing to the mouth of the coral. These are little signs that ejaculation on a mass scale is about to take place.”

Meanwhile, two Quicksilver Reef Biosearch marine biologists, Dr Glen Burns and Graham Carroll, spent last night at Agincourt 3 on high spawning alert, waiting to capture the event.

“The water temperature on the edge of the outer reefs was perfect for coral spawning, so we were pretty confident,” Dr Burns said. “We witnessed the branching staghorn coral, shrubby corals and a magnificent plate coral spawning.  We were privileged to record this at Agincourt Reef.”

The spawning is likely to continue for the next two nights.



Footage credit: Graham Carroll, Quicksilver Marine Biologist


Megan Bell, Quicksilver Group Media Manager

0412 570 268