A newly discovered coral reef off Tahiti could prove there could be more ecosystems deep in the ocean that haven’t been damaged by pollution and global warming, scientists hope.
Stretching for thousands of meters, the pristine rose-shaped corals are a sight to behold.
It’s one of the rarest finds of its kind – an unspoilt reef that’s not only bigger than most but also much deeper.
Most corals are found at depths greater than 25m – where they receive most of the sunlight they need to reproduce.
But this huge reef, discovered in French Polynesia by a team of UNESCO scientists, extends from 30m to 70m – in what is called the “twilight zone” of the ocean.
It is thought that being so deep may have protected the reef from the worst ravages of global warming.
UNESCO’s Julian Barbiere told Sky News: “We’ve lost around half of our coral reefs over the past 70 years. But it’s healthy, it’s vast, and that means it can there are other parts of the world where we have similar coral reefs at those sort of depths.
“It’s really the stuff that makes you dream – that makes you understand the treasure and the beauty of the marine environment.”
A team of scientists located and measured the reef using state-of-the-art diving equipment.
Until recently, very few scientists were able to study reefs at depths greater than 30m due to the limitations of traditional equipment.
But divers can now use advanced equipment like rebreathers which use a specialized gas mixture to allow them to stay deeper for much longer periods.
After 200 hours of diving, the team measured the reef at 3km long and up to 65m wide – with some of the individual corals measuring 2m wide.
This makes it one of the largest reefs ever discovered at these depths. It also suggests that more of the world’s preserved reefs could be located this far below sea level – exciting news for marine conservationists.
“Coral reefs are very important for the health of the oceans – we know that they are home to around 25% of all the species we find in the marine environment,” Barbiere said.
“Reefs are also where we can potentially find new species and new drugs.
“We are increasingly deriving drugs from marine organisms, especially to treat cancer, arthritis and infections.
“They also protect local communities from storms and tsunamis, and generate a lot of income through tourism.”
More dives are planned in the coming months to study the reef and the marine life it supports.
UNESCO will also work with local communities to give them the tools they need to protect it – such as designating marine protected areas.
The discovery illustrates how little is still known about the underwater world.
Currently, only about 20% of the planet’s seabed has been mapped, meaning we know more about the surface of the moon than we know about the depths of the ocean.
The Intergovernmental Oceanographic Committee – part of UNESCO – is currently working with other organizations and governments to try to complete the mapping of the seabed by 2030.
Along the way, the hope is that more unique and valuable ecosystems may well be discovered.