By Anders Lorenzen

Ocean scientists and naturalists such as David Attenborough are keen to remind us often of the demise of the Great Barrier Reef and other coral reefs. 

But some optimism might be afoot, as a new coral reef in good condition has been discovered near Tahiti.

A scientific research mission supported by the UN body UNESCO has discovered one of the largest coral reefs in the world off the coast of Tahiti. The rose-shaped corals are said to be in pristine condition and cover an extensive area.

The reef

The corals are up to 2 metres in diameter, are located at depths of between 30 and 65 metres, and are approximately 3km in length and between 30m and 60-65 m wide. Therefore, this discovery has uncovered one of the most extensive healthy coral reefs on record.

Scientists say this is highly unusual because up to now the vast majority of the known coral reefs in the world sit at depths of up 25m. Scientists believe that this discovery gives hope that there may be many more large reefs at depths of more than 30 metres waiting to be discovered. 

Like a work of art

Alexis Rosenfeld, French photographer and founder of the 1 Ocean campaign, who led the diving mission explains: “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” 

Audrey Azoulay, Director-General of UNESCO added: “To date, we know the surface of the moon better than the deep ocean. Only 20% 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”. 

The expedition is part of a global approach to mapping the ocean. As coral reefs are an important food source for other organisms, locating them can aid research around biodiversity. In addition, the organisms that live on the reefs can be further used as they can be important for medical research, and can also provide protection from coastal erosion and tsunamis

There was also optimism that this reef does not appear to have been impacted by bleaching. Dr Laetitia Hedouin from France’s National Centre of Scientific Research (CNRS) and the environmental research body CRIOBE who was present on the mission 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.” 

New technology now means it is easier to study reefs at depths of more than 30m, previously that was very tricky

At a time of dire warnings about the impacts of climate change on the world’s oceans and, in particular, that many of the known coral reefs in the world are impacted by climate change, this new discovery is set to inject hope and optimism into the ocean conservatory movement.