World's coral reefs can still be saved

Managing corals so they thrive may hold the secret of saving the world’s coral reefs in a time that might otherwise bring near-extinction, say experts.

John Pandolfi, a renowned coral scientist from the ARC Centre of Excellence for Coral Reef Studies and University of Queensland, has traced the story of the world’s reefs over more than 50 million years and is deciphering delicate signals from the past to reveal what doomed them in previous extinctions – and how this compares with today.

This knowledge is priceless in understanding what we humans have to do to prevent such a tragedy recurring, he said. Despite scientific predictions that the current trajectory of human development will eliminate 90 per cent of the world’s coral reefs by the end of the century, Pandolfi considers it is still within our power to save 60 or70 per cent, provided we act quickly to limit the things that drive corals to ruin.

“Corals themselves are remarkably resilient. They have stood up to several episodes of global warming and high CO2 in the past – and bounced back, even from mass extinction events,” he noted.

But the sobering fact is that it can take coral reefs up to ten million years to re-establish after a major extinction event, he said adding, “That’s a long time to wait if your industries, communities and food supplies are dependent on reefs.”

The big issue today is that most of the world’s coral reefs face a ‘double whammy’ of accelerated global change combined with local stresses from pollution, runoff and overfishing. These local, man-made, factors were absent during previous world coral crises, he pointed out. The good news, he said, is that experiments in Australia and round the world have shown it is possible to curb overfishing, runoff and pollution, to limit their local impact on corals.

Prof. Pandolfi indicated that the action required is threefold – (i) aggressively reduce CO2 emissions (ii) reduce overfishing, pollution and coral habitat destruction and (iii) implement sound management to improve overall reef health.