'Pristine' Reef Discovered Off Coast of Tahiti Described as One of Largest in World

The discovery of one of the largest coral reefs in the world off the coast of Tahiti could be promising for the future of coral reefs and conservation.

Researchers said the discovery, part of a scientific mission supported by UNESCO, is valuable for multiple reasons, according to the organization.

The reef consists of a large area approximately 3 kilometers in length and between 30 and 65 meters wide. Rose-shaped corals found at the site are up to 2 meters in diameter.

The reef is also important because of its depth, between 30 and 65 meters. Researchers said this is "highly unusual" because the vast majority of the world's known coral reefs are no deeper than 25 meters.

This means that there may be a plethora of unknown reefs in water bodies that extend deeper than 30 meters, in what researchers call the ocean's "twilight zone."

"To date, we know the surface of the moon better than the deep ocean," said UNESCO Director-General Audrey Azoulay. "Only 20 percent of the entire seabed has been mapped. This remarkable discovery in Tahiti demonstrates the incredible work of scientists who, with the support of UNESCO, further the extent of our knowledge about what lies beneath."

Coral Reef Tahiti
Researchers examine a newly discovered coral reef off the coast of Tahiti. Alexis Rosenfeld

Alexis Rosenfeld is a French photographer and founder of the 1 Ocean campaign, which works in partnership with UNESCO for the Decade of Ocean Science for Sustainable Development. Video released by UNESCO showed Rosenfeld and others in the depths of the reef, taking photographs for future research.

Every year until 2030, expeditions are being executed across oceans to find new threats and improve preparedness for solving real-time and future issues.

"It was magical to witness giant, beautiful rose corals which stretch for as far as the eye can see," said Rosenfeld, who photographed the experience. "It was like a work of art."

Coral reefs are an important food source for other organisms, UNESCO said, so new discoveries aid biodiversity research. Organisms that live on reefs can be integral for medicinal research, while the reefs themselves can provide protection from coastal erosion and even tsunamis.

Laetitia Hedouin of France's National Center of Scientific Research said that although French Polynesia suffered a significant bleaching event in 2019, this newly discovered reef does not seem to be significantly affected.

"The discovery of this reef in such a pristine condition is good news and can inspire future conservation," she said. "We think that deeper reefs may be better protected from global warming."

Newsweek reached out to UNESCO for comment but did not hear back before publication.

Coral Reef Tahiti
A magnified view of the reef's large corals, where were found deeper than usual in the ocean. Alexis Rosenfeld