A team of divers discovered a pristine coral reef near the coast of Tahiti at depths beyond 30 meters below the surface, according to UNESCO

The reef features rose-shaped corals that, together, span 3 kilometers (approximately 1.86 miles) in length and 60 meters (nearly 200 feet) wide. The most remarkable aspect of the discovery is that the reefs remain intact, unscathed by the bleaching events — largely caused by warming waters due to climate change — that have scarred so many other reefs around the world. 

“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.”

The vast majority of coral reefs occupy space less than 25 kilometers below the surface, which makes the latest discovery something of an anomaly. 

But what the finding suggests is that more intact reefs at similar depths likely exist around the world, especially since only 20% of the seabed has been explored. As new reefs come to light, scientists may be able to develop insights that help in coral reef preservation.

Image: Courtesy of @Alexis.Rosenfeld

“We still associate corals with the shallowest tropical seas but here we find a huge, previously unknown coral reef system,” Murray Roberts, a marine scientist at the University of Edinburgh, told the BBC

“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.

Few ecosystems have been devastated by climate change as extensively as coral reefs. More than 14% of reefs have been lost in recent years and up to 90% could be destroyed if global temperatures continue to rise because of emissions. 

The ocean absorbs the majority of excess heat trapped in the atmosphere. As a result, it’s experiencing frequent heat waves that create oven-like conditions for sea creatures. 

Corals are especially vulnerable to temperature changes and undergo a process called “coral bleaching” when excessively stressed in this way. Bleaching is when coral expel the symbiotic microorganisms that give them color and turn white as a result.

Coral reefs that were once vibrant mosaics of color now look like bony graveyards. Over time, they can disappear entirely, unable to bounce back from heat waves. 

Scientists have developed all sorts of unlikely measures to help reefs adapt to climate change, including bolstering coral microbiomes, deploying lab-created coral, and propagating the hardiest varieties of coral

But even if some of these measures prove successful, a large percentage of the more than 900 currently known coral species could still go extinct.

One of the most effective ways to protect coral, then, is to limit the greenhouse gas emissions causing ocean temperatures to spike. But even more has to be done, scientists warn.

Image: Courtesy of @Alexis.Rosenfeld

Countries also have to limit the overfishing that’s hollowing out reef ecosystems and the widespread marine pollution that’s poisoning them.

The new rose-shaped reef shows that the planet has not yet irreversibly changed. With a collective effort, the global environment can recover from the harms of the past century and return once again to an equilibrium that allows thriving coral reefs to be the norm. 


Defend the Planet

'Magical' Coral Reef Discovery Near Tahiti Gives Hope to Scientists

By Joe McCarthy