An astonishing find: Pristine giant coral reef discovered near Tahiti

Written by Oceanographic Staff

A scientific research mission supported by UNESCO has discovered a large, pristine coral reef at unexpected depths off the coast of Tahiti. The pristine condition of, and extensive area covered by, the rose-shaped coral reef make this a highly valuable discovery.

Within the depth of the South Pacific, a research mission has made a highly unusual discovery. It found a pristine coral reef near Tahiti with giant rose-shaped corals at depths of between 30 and 65m. The so-called ‘twilight zone’ is a highly unusual location for coral reefs as the majority of the world’s known coral reefs sit at depths of up to 25m. “It was magical to witness giant, beautiful rose corals which stretch for as far as the eye can see. It was like a work of art,” said Alexis Rosenfeld, French underwater photographer and founder of the 1 Ocean campaign that discovered the reef.

With an approximate length of 3km and a width of between 30m and 60 to 65m, the newly discovered coral reef near Tahiti suggests that there might be many more large, undiscovered reefs in the oceans that lie at depths of more than 30m.

Dr. Laetitia Hedouin from France’s National Centre of Scientific Research (CNRS) said: “French Polynesia suffered a significant bleaching event back in 2019 however this reef does not appear to have been significantly affected. The discovery of this reef in such a pristine condition is good news and can inspire future conservation. We think that deeper reefs may be better protected from global warming.”

The expedition was part of the ‘1 Ocean, the anatomy’ campaign that partners with UNESCO and was led by explorer photographer Alexis Rosenfeld. Until now very few scientists have been able to locate, investigate and study coral reefs at depths of more than 30m.

However, technology now means longer dives at these depths are possible. In total the team carried out dives totalling around 200 hours to study the coral reef near Tahiti and were able to witness the coral spawning. Further dives are planned in the coming months to continue investigations around the reef.

For more from our Ocean Newsroom, click here.

Photography courtesy of UNESCO/Alexis Rosenfeld/1 Ocean.

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