Meet some of the players (and spectators) in this year’s massive coral spawning event

This weekend one of the world’s biggest sex events is happening under water off the north Queensland coast.

The annual mass coral spawning event, set to happen over three nights from Friday, will see the corals of the Great Barrier Reef release trillions of eggs and sperm into the water.

This year you can catch this incredible natural phenomenon during Reef Live, a two-part live ABC TV event.

But the more than 800 recognised coral species are just the start of the food chain for Australia’s magnificent Great Barrier Reef. It’s home to an abundance of other wildlife — each playing a critical role in keeping the ecosystem balanced.

Here are seven creatures that you’re likely to come across when you visit the reef.

Acropora millepora