An intact coral reef discovered off the coast of Tahiti

Photo by @alexis.rosenfeld

Scientists have discovered an unique stretch of virgin corals shaped like roses off the coast of Tahiti deep in the South Pacific. The reef is believed to be one of the biggest ever discovered at such depths, and it appears to be unaffected by climate change or human activity.

Laetitia Hédouin first observed the corals months ago during a leisure dive with a local diving club.

"When I first visited there, I said to myself, 'Wow, we need to study the reef.' Hédouin, a researcher at the French National Center for Scientific Research in Moorea, French Polynesia, observed, "There's something exceptional about that reef."

What impressed Hédouin was the fact that the corals appeared to be in good health and had not been impacted by the 2019 bleaching incident. Corals are small creatures that grow and form reefs in oceans around the world.

Overfishing and pollution have devastated coral reefs throughout the world. Warmer seas are also damaging delicate corals, particularly those in locations near the newly found reef, which are suffering from severe bleaching as a result of climate change. According to a 2020 study by the Global Coral Reef Monitoring Project, 14 percent of the world's corals were perished between 2009 and 2018.

The undiscovered reef, which stretches for 2 miles, was discovered late last year during a UNESCO-sponsored diving trip. Unlike the majority of the world's documented corals, which are located in relatively shallow seas, this one was found in deeper depths, ranging from 115 feet to 230 feet (60 meters).

Photo taken by Alexis Rosenfeld/@alexis.rosenfeld

Exploring such depths was difficult since the deeper a diver goes down, the less time he or she can spend safely at each depth. The crew used customized tanks and dived for 200 hours to research the reef, which included capturing photos, measurements, and coral samples.

The reef is in a spot where many researchers haven’t spent a lot of time in, said former National Oceanic and Atmospheric Administration oceanographer Mark Eakin.

Hédouin expects that the study will assist scientists better understand how the reef has resisted climate change and human stresses, as well as what function these deeper corals may play in the ocean environment. In the next months, further dives are planned.