Dark times for coral

© David Hannan

While Tara left the Great Barrier Reef, we had the chance in Sydney to meet with Ove Hoegh-Guldberg, professor at the University of Queensland, Australia. He is one of the world’s most prominent researchers and specialists on coral. The third global coral bleaching event recently ended in May, with dramatic new consequences for all reefs, including in Australia. Ove evoked for us the possible evolution of the situation which, according to him, is not desperate.

Pscchh, pscchhhh –The biologists who recently arrived aboard Tara are out on the rear deck, testing the diving equipment attributed to them by dive master Jonathan Lancelot. In a few days, using these tanks they will go diving around the largest coral structure still alive on the planet.


2- photo 7_ scientifiques essais materiel_Vincent HilaireThe chief scientist, Christian Voolstra tries his diving equipment – © Vincent Hilaire / Tara Expeditions Foundation


Classified by UNESCO as a World Heritage site in 1981, the Great Barrier Reef (GBR) is 2,300 kilometers long and represents an area equivalent to that of Germany. This eighth wonder of the world is home to 600 species of corals, 3,000 reefs, 1,625 species of fish, 133 species of sharks and rays, etc.

This underwater garden, endowed with exceptional biodiversity, has been studied by Ove for more than 40 years.


6- NASA 3_P11 NASA _ GSFC _ LaRC _ JPL, MISR Équipe Southern Great Barrier Reef – © P11 NASA _ GSFC _ LaRC _ JPL, MISR Équipe

Vincent Hilaire :

This third episode of global coral bleaching just ended after 3 years of continuous stress caused by rising ocean temperatures. To date, 50% of the GBR’s corals have died. Have we entered an irreversible situation here?

Ove Hoegh-Guldberg :

There’s no longer any doubt about ongoing global climate change and its direct impact on corals, causing their bleaching. We have entered a lasting dark period for reef life and the damage is likely to continue if we do nothing. Another direct cause of reef destruction is storms – hurricanes, cyclones, typhoons. The 2 phenomena combined are massively destroying the coral.


Vincent Hilaire :

According to our information, the Marine Park of New Caledonia will not escape this trend after the third massive bleaching. Classified more recently (in 2008) by UNESCO, this second largest reef on the planet (after the GBR) is following the same trend. What can you tell us about this?

Ove Hoegh-Guldberg :

The impacts are about the same in this southwestern part of the Pacific – about 50% mortality. What I can say about the situation in Australia and New Caledonia (France) is that we are 2 coral reef “superpowers”. Let me explain: even if 90% of the coral in this Pacific zone is eventually destroyed, our 2 countries must seek and find solutions. We must join together to vigorously enforce the Paris Climate Agreement. That’s how we will reduce the impacts of CO2 emissions. We know that the key is maintaining temperatures below 2° C. In some reefs, heat waves affecting the ocean operate to a lesser extent. These coral colonies give us hope. Resilience is possible, not everything is uniform.

But if we do nothing to act on the climatic factor, we’ll no longer have coral reefs in the future.

With Tara Pacific and all the followup work done by researchers on the basis of these samples, the first genomic library of the Great Barrier Reef will be established. We’ll know more and understand better the processes guiding the life of coral. If there’s a strong political will, we can succeed.

Vincent Hilaire

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