This story was originally published in the Guardian and is reproduced here as part of the Climate Desk collaboration.
A huge coral reefIt was discovered off of the coast of Tahiti in the Pacific Ocean’s “twilight zone,” offering hope that more pristine ecosystems are waiting to be discovered at unexplored depths.
The reef is nearly two miles long and covered in rose-shaped corals. It can be found at depths of 30 meters or more, where sunlight levels are lower.
Scientists are needed for the Unesco-led mission French PolynesiaAccording to researchers, the reef was not affected by bleaching events that may have damaged nearby reefs in shallower waters in 2019. Researchers were able witness coral spawning during 200 hours of diving. Some corals spanned two meters.
“It was magical to witness giant, beautiful rose corals which stretch for as far as the eye can see,” said Alexis Rosenfeld, a French underwater photographer who was part of the team of international divers that made the discovery. “It was like a work of art.”
Researchers found that there were likely to be more reefs at these depths, thanks to advances in diving technology.
“To date, we know the surface of the moon better than the deep ocean. Only 20 percent of the entire seabed has been mapped,” said Audrey Azoulay, Unesco’s director general.
Most of the world’s known coral reefs are at depths of 25 meters and above, with many facing the risk of collapse as the world’s oceans continue to heat. September will be the hottest month in history. A study found coral reef coverage had fallen by half since the 1950s because of global heating, overfishing, pollution and habitat destruction.
Prof Murray Roberts, a University of Edinburgh marine scientist, spoke to BBC. He said that the discovery highlighted the need to map similar reefs in order to ensure their protection in the future. “We still associate corals with the shallowest tropical seas but here we find a huge previously unknown coral reef system.
“As shallow waters warm faster than the deeper waters we may find these deeper reef systems are refuges for corals in the future. We need to get out there to map these special places,” He said.
To continue the investigation of the reef, additional dives will be made off Tahiti in the months ahead.