CORALS in waters off the Coffs Coast are returning to health in the wake of one of the largest bleaching events in recent history.
Early research suggests coral mortality rates have been limited to the northern side of South Solitary Island after water surface temperatures as high at 27.5 degrees were recorded in the Solitary Islands Marine Park over summer.
The hot temperatures initially caused an outbreak as far as South West Rocks, but cooling temperatures in recent weeks have turned fortunes around.
Steven Dalton from Southern Cross University said many corals had started to regain their colour.
"We have done follow-up observations in a lot of the affected areas and it looks like the micro algae is coming back into the tissue of the corals which is a good sign," he said.
"There are still a couple of sites where there's going to be a reasonable amount of mortality in the most affected species.
"It's a community of thousands of polyps living together attached - some parts may not die, which are normally in the shaded areas.
"If we don't get any more heating events in next four to five years it should recover."
SCU has joined research efforts on the Great Barrier Reef and Torres Strait to monitor widespread devastation of coral systems.
"It will give us an indication about how things are travelling over a longer period of time, for example if there is increasing severity, how will coral community react to that?" Steven said.
Researchers will conduct another survey in the South Solitary Islands after winter.