A group of citizen scientists stumbled across an enormous ancient coral during a recent expedition on the Great Barrier Reef. The discovery was made by students taking a marine citizen science course and shows that after all these years we are still learning new things about this incredible ecosystem.

Reef scientists have described the 5.3-metre tall coral as an "apartment block" for marine life.

"It attracts other species. There's other corals, there's fish, there's other animals around that use it for shelter or for feeding, so it's pretty important for them,” James Cook University adjunct associate professor and managing director of Reef Ecologic, Adam Smith told The Guardian.

James Cook University runs a research facility on Goolboodi (Orpheus Island) adjacent to the patch of Reef where the discovery was made. There have been around 600 scientific papers written on corals, fish and seaweed in the area, but this giant coral had not been properly documented until now.

"It's a bit like finding a giant redwood tree in the middle of a botanic gardens," Smith explained.

"Over the last 20 or 30 years, no one has noticed, or observed, or thought it newsworthy enough to share photos, or document, or do research on this giant coral."

The coral is between 421 and 438 years old and roughly the same size as a double-decker bus. Traditional Owners of the lands and waters where the discovery was made have named the coral Muga dhambi, which translates to "big coral".

The citizen scientists who documented the coral have called for it to be monitored and for the Reef to be protected against threats of coastal development, poor water quality, overfishing and climate change.

Muga dhambi has stood sentinel for hundreds of years, watching the Reef transform around it.

"It's lived through lots of cyclones, quite a few reefs and coral bleaching events — who knows? It's a very diverse, hard environment on the Great Barrier Reef. It's obviously an old resilient coral," Smith said.

"Whether that's because it's tough or lucky, I don't know."

With recent government lobbying against UNESCO listing the Reef as critically endangered, this discovery is a timely reminder of both the threats that face the Reef and the incredible resilience of this ecosystem.

Positive Environment News has been compiled using publicly available information. Planet Ark does not take responsibility for the accuracy of the original information and encourages readers to check the references before using this information for their own purposes.