One of the amazing occurrence in aquatic life would be the coral spawning. The first recorded sighting of this phenomenon was late 1980's, when a group of scientists set out in Australia's Great Barrier Reef during a night swim. After that encounter, scientists finally figured out the day this occurs in the Australian coast.

Each year, coral spawning occurs 5 nights after the full moon of spring. Which falls on the end of October or November and December each year. The times of coral spawning differs in the Eastern Coast than that of the Western Coast in spite of most of the reefs share the same variety of coral. Experts attribute this to the position of the moon at any given corner of the world.

Most Coral reproduce asexually. Meaning within the coral, eggs and sperm. For Coral to spawn, certain changes are required of their habitat. Studies show that a small rise in aquatic temperature trigger the eggs and sperm to develop in an adult coral. By some strange chance, the lunar cycle synchronizes its start at exactly at the same moment the coral releases reddish egg cells into the water.

The sight of the lots of bubble-like eggs floating around is likened to floating in champagne. A moment after this the corals spew a pink slick, which is it's sperm. The pink slick is a long sticky substance that blankets the surrounding water as coral eggs float to the surface. Amazingly the coral's egg cells can distinguish pink slick coming from its own parent colony which it readily rejects. Coral does accept sperm from a different colony of the same specie though.

For the reddish coral eggs and pink slick to mix, a small tidal difference is required. This happens during neap tide when the lowest high tide is possible. This is important for spawning since calm water prevents the eggs and sperm to quickly disperse in normal water current.

As the egg is fertilized and embryo will develop in approximately 24 hours. This embryo, gets carried by the current, slowly taking around 5 days to drop to the bottom. This is one of the ways coral reefs span most of the coastal waters. It is said that most of coral at the Great Barrier Reef simultaneously spawn while the others would spawn after a few minutes of the first salvo.

Though coral spawning multiplies the coral by the thousands, its average life expectancy is debatable. Since the growing coral colonies have to elude dying out. Sadly disasters, natural or man-made contribute to its decline. Unless these corals are replaced through successful reproduction followed by settlement and metamorphosis of the coral seed called granular larvae, the reef goes into decline, and the important functions and benefits of the coral reef are lost.