How does coral spawning work and why is it synchronized?
Once a year, entire coral reefs release billions of eggs simultaneously in a breathtaking underwater snowstorm.
The answer
Mass coral spawning is one of nature's most spectacular events, where entire reef systems release eggs and sperm bundles into the water column simultaneously over just a few nights each year. On the Great Barrier Reef, this typically occurs after the full moon in late spring, when water temperature, lunar cycle, and day length all align. The synchronization maximizes the chances of cross-fertilization while overwhelming predators with sheer numbers. Scientists believe corals use blue light receptors to detect moonlight intensity and chemical signaling to coordinate their timing, though the exact mechanism remains partially mysterious.
Source: Australian Institute of Marine Science
- coral spawning
- coral reefs
- reproduction
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