Great Barrier Reef Coral Spawning Event: November 2021
The corals of the Great Barrier Reef have [beginning Nov. 23] spawned trillions of eggs and sperm, in an annual simultaneous mating event.
The mass spawning occurs after a full moon, and only after rising water
temperatures have stimulated the maturation of the gametes, within the adult coral. The day length, tide height, and salinity levels also appear to be factors in deciding when the event will happen.
The spawning lasts between a few days, and a week. This is because different species release their eggs and sperm on different days, to prevent hybrids from being produced.
The phenomenon, which only happens at night, resembles an underwater snowstorm. But rather than being all white, there are also clouds of red, yellow, and orange. All the bundles rise slowly to the surface, where the process of fertilisation begins.
While spawning takes place on a large scale, it doesn’t happen across the entire Reef all at once.
Instead, the time of year that corals spawn depends on their location. Those on inshore reefs
usually start spawning one to six nights after the first full moon in October, whereas those in outer reefs
spawn during November or December.
GBR Foundation ➥ https://www.barrierreef.org/news/new...its-protection
ABC ‘Far North’ News ➥ https://www.abc.net.au/news/2021-11-...reef/100645572
7NEWS Video ➥ https://youtu.be/rKjvtkZWWbs