It perhaps may not have thrilled the female of the coral species but marine biologists are excited by a spectacular marine event that saw the majority of Great Barrier Reef coral spawn in less than two hours last week.

So excited are the specialist reef folk from James Cook University, they have dubbed the event the "world's biggest orgy".

An alignment of perfect conditions has allowed a mass coral spawning to occur on the Great Barrier Reef.

It was, according to Associate Professor Jamie Seymour of the Cairns-based Australian Institute of Tropical Health and Medicine, one of the most spectacular events he has seen in 30 years of studying the reef.

"Visually it was mind blowing," he said.