UNESCO researchers have discovered a very special and healthy coral reef. A glimmer of hope for all reefs in danger?
Our planet is full of unsuspected treasures, many of which lie in the depths of the oceans. Last November, in the South Pacific Ocean, researchers affiliated with UNESCO made an incredible discovery; near Tahiti, they came across a huge very special coral reef, and in excellent health. They have just published the absolutely grandiose images of their exploration.
We discover a magical landscape, where each meter of ground is studded with elegant volutes of coral. Indeed, visually, this reef has little to do with the most famous of them, such as the Great Barrier Reef. Here there is no point in looking for the famous characteristic ramifications; instead, there are kinds of giant “roses”, which can exceed two meters in diameter.
“It was magical to observe these magnificent giant coral roses as far as the eye could see”, explains Alexis Rosenfeld, French underwater photographer affiliated with the mission to whom we owe these exceptional images.
A sumptuous field of roses on the edge of the abyss
A size which, according to the researchers, indicates that this reef has probably been thriving for several decades. If this landscape resembling an extraterrestrial botanical garden has remained invisible for so long near a tourist hotspot, it is because of its unusual location. Indeed, this reef has taken up residence between 30 and 70 meters deep, much deeper than the usual corals.
Indeed, only one tiny fraction of sunlight is able to make its way to this depth. It is therefore a somewhat special area; the most sensitive organisms do not risk it, but those that live there are generally true survivors, with specific adaptations that have allowed them to settle at the edge of the abyss.
And the superb rosettes that make this coral so photogenic are precisely one of these adaptations. Indeed, corals feed almost exclusively by filtering the plankton present in the water, whether plant (phytoplankton) or animal (zooplankton). But the low amount of available light means that these preys, usually available in abundance, are rather rare at this depth.
This scarcity of prey constitutes a selection pressure; these corals have been forced to adapt over generations to survive. As it happens, natural selection ended up favoring this strange flattened shape; this therefore gives petals with a very large filtration surface, which allows them to sustain themselves despite the scarcity of prey.
A real badass
But this reef is not only a source of breathtaking shots; it is also an exceptional ecosystem in many respects scientifically and ecologically. “For once it’s a positive story about a coral reef, which is pretty rare these days.”, rejoices Julian Barbiere, head of the marine division of UNESCO.
What makes the researchers so enthusiastic is above all the state of conservation of this reef, which the researchers consider “unparalleled” at present. Indeed, it is an exception at a time when the majority of reefs are being damaged by global warming, changes in marine biodynamics and ocean acidification.
The researchers were therefore surprised to find such a dashing reef. They will continue to study this reef with particular attention; so they hope in learn more about how these corals manage to survive despite the changing conditions of their environment, while their congeners are often in poor condition. These findings can then be incorporated into coral conservation efforts.
“We believe that these deeper reefs are better protected from global warming”, explains marine biologist Laetitia Hédouin to CNN. “The discovery of such a pristine reef is great news that can inspire further conservation work.”, she specifies.
The fate of corals, an absolute emergency
This would indeed constitute a ray of hope for these absolutely fundamental species in marine biodynamics. And there is urgency; some researchers estimate that half of the corals present in 1950 may have already disappeared. Other work suggests that by 2100, acidification could eradicate corals once and for all.
This would be a real ecological disaster, because corals do not exist in a vacuum. They are absolutely major players in their ecosystems; the survival of thousands of species of animals and plants of all kinds therefore depends directly on the relationship they have with coral, directly or indirectly. If the latter were to disappear, it would sound the death knell for a large part of these species and for all marine biodynamics as we know it, with catastrophic consequences for the biosphere.
For researchers, this is therefore the perfect opportunity to recall the importance of our oceans. They also insist on the fact that science must absolutely devote considerable resources to it. “We see major investments in space exploration coming, when we don’t even have enough funds to study our own home, and the ocean in particular.”, laments Julian Barbiere to CNN. “I think this is something that needs to be emphasized over the next decade – creating the knowledge needed to put the planet back on a healthier path through ocean conservation.”, he concludes.