Scientists have discovered corals living at extreme depths on
the Great Barrier Reef.
The Catlin Seaview Survey team, which is mapping reefs
threatened by climate change around the world, found corals
living 125 metres below the surface of the ocean in late
December. They were the deepest ever found on the reef.
The extreme depth is more than four times that of the shallow
reef corals, which are usually about 30m down.
Dr Pim Bongaert, who led the expedition to the outer Ribbon
Reefs, says the discovery of coral where sunlight is so
scarce is mind-blowing.
"It's intriguing. When we began our survey, we were amazed to
see significant coral communities at depths of around 60
metres," he said in a statement.
"It is truly mind-blowing to see reef coral at more than
twice that depth and four times deeper than most scuba divers
"There are coral communities on the Great Barrier Reef
existing at considerably greater depths than we could ever
The survey also collected samples of large Staghorn Acropora
corals living at a depth of 73m, the deepest they have been
Dr Bongaert said the team would analyse the specimens to find
out what enabled reef corals to survive at such extreme
"These discoveries show just how little we really know about
the reef and how much more is yet to be discovered," he said.