New, Vast Coral Reef Discovered

Marine ecologists have just discovered a vast and untouched coral reef near the Tahitian coast in French Polynesia. The reef spans nearly 3.2 kilometres and resides between 35 and 70 metres below the surface — a space known as the ocean’s “twilight zone.” The United Nations Educational, Scientific, and Cultural Organization (UNESCO) is now leading the mission to map the grove and search for more like it.

Giant pristine coral reef discovered off Tahiti

Photo: Alexis Rosen

Coral and the twilight zone

Overfishing and scourges of pollution have greatly depleted coral reefs in recent years. Between 2016 and 2017, 89% of the Great Barrier Reef collapsed due to climate-induced bleaching. A report published in One Earth journal last fall found that human-caused erosion has degraded 50% of the globe’s coral since 1950.

The reef was found in November, during a seabed mapping expedition to the ocean’s largely unexplored twilight zone.

Unlike many of Earth’s reefs, the one found near Tahiti is flourishing. The reef’s depth positions it far enough from the surface to protect it from coral bleaching and destructive human activity, yet close enough to give it adequate sunlight. Its discovery has given some scientists hope.

According to Dr. Julian Baberbie, one of UNESCO’s marine ecologists, coral reefs are home to about 25% of all marine life.

“The next stage is to find what species live around this type of reef,” he 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…and make sure we protect them for the future.”