AT THE EDGE: University of New South Wales Associate Professor Tracy Ainsworth at Heron Island during a recent research project studying coral bleaching.
AT THE EDGE: University of New South Wales Associate Professor Tracy Ainsworth at Heron Island during a recent research project studying coral bleaching. UNSW

Startling new insights from coral study at Heron Island

NEW coral research conducted on Heron Island will help inform a study later this year into reef restoration and rehabilitation.

The University of New South Wales study found severe heating caused immediate mortality to a reef colony, rapid skeletal dissolution and loss of structure faster than first thought.

The report, Rapid Coral Decay Is Associated with Marine Heatwave Mortality Events on Reefs, published this month used healthy coral in a controlled environment to simulate a coral-bleaching event.

Associate Professor Tracy Ainsworth said they found the coral animal died rapidly when pushed beyond it's temperature limits.

"Because we've got a warm environment with lots of light, algae colonise that skeleton really quickly and they actually erode through the skeleton and degrade it, which causes it to become quite weak and break quite easily,” Prof Ainsworth said.

This also had flow-on effects for marine life which live in coral.

"As little as 0.5 degrees Celsius can be the difference between a coral bleaching and surviving,” she said.

"We're already a quarter of a degree above historic and we're seeing coral right at the edge of their tolerance.

"Every little bit we go up takes the temperature beyond the upper limit that they're used to.”

Prof Ainsworth said although the findings were negative there was still a lot that could be done to help the reef.

"We are using this research to try and better understand how local interventions might help and what things people can do to help improve the health and resilience of the reef,” she said.

"If we know what's coming we can prepare for it as well as possible.”

This research would have a strong influence on the university's next study.

"We want to start looking at the restoration ideas that are out there about how do we best improve these places (in the reef) that have been impacted,” she said. "It's really important that we know how these systems degrade so we know the best approach to restore them and rehabilitate them.”

Prof Ainsworth said individual actions to make society more sustainable and efficient, such as reducing plastic use, helped the reef.

"There's always going to be hope for the reef,” she said. "Corals are quite amazing organisms and what's important is that we make sure our reef stays the best in the world.”