WA’s super-corals could help protect other corals

Researchers have found corals occurring in Western Australia’s Kimberley region are more resistant to changes in water temperature and the effects of coral bleaching than corals found elsewhere.

Ningaloo reef, Western Australia. Image by peter boer / CC BY 2.0

The discovery, published in Nature Scientific Reports, could help scientists in the fight to protect coral reefs around the world from the devastating effects of coral bleaching.

Most of the world’s coral reefs are found in waters in tropical latitudes, which experience very slight variations in temperature seasonally – just 4°C to 5°C – and reach maximum temperatures of just 30°C. Because they have evolved in a relatively stable environment, these corals are highly susceptible to changes in ocean temperatures and have been severely impacted by coral bleaching.

However, researchers have discovered corals found in the Kimberley region are made of sturdier stuff. These ‘super corals’ are subject to extreme conditions including the largest tropical tides in the world, strong currents, turbid waters, average temperatures of over 30°C for five months a year and daily fluctuations in temperature of up to 7°C. And they not only survive, but thrive.

Staghorn coral showing evidence of coral bleaching. Image by SarahDepper / CC BY 2.0

Though the study indicated that Kimberley’s corals would still be vulnerable to changes in water temperature resulting from climate change, they are more resilient in the face of rising temperatures than corals found elsewhere. “While the coral from the most extreme environment resisted bleaching for longer than corals from less extreme environments, they still bleached,” Dr Verena Schoepf, from the Australian Research Council Centre of Excellence for Coral Reef Studies at the University of Western Australia’s Oceans Institute, told the ABC.

The researchers suspect the longer coral takes to bleach, the faster it will recover from the effects of bleaching. Based on what they have learned from studying the Kimberley corals, researchers are undertaking a new study to determine whether coral can increase its heat resistance to keep pace with rising sea temperatures. “We’re trying to see if the coral from the less extreme environments can acquire the same heat resistance as the coral in the more extreme environments, by just putting them in the more extreme areas,” Dr Schoepf explained.

Though the discovery of super corals won’t solve the issues of rising sea temperatures or the devastating effects of coral bleaching, Dr Schoepf acknowledged “It gives us a little bit of hope for the future of coral reefs.”