"Devastating" damage to Australian coral reefs could be permanent: scientists

Damage done to coral reefs off the coast of Western Australia (WA) could be irreversible, scientists have warned.

Scientists from the Australian Institute of Marine Science (AIMS) said that observing the damage done to Scott Reef, off the state's north coast, was "devastating."

The reef was hit by one of the worst coral bleaching events in history last summer due to a global warming and an El Nino weather system which caused high water temperatures.

James Gilmour, a marine scientist with AIMS, said the team was hopeful the reef could have survived the event but it now seems as if the damage was permanent.

"This was devastating for all of us," Gilmour told the ABC on Tuesday.

"We confirmed that in fact most of the corals that we had seen that bleached were in fact dead this time - so much of the reef was dead and now covered in algae, which was a great shock to us."

Coral bleaching occurs when rising water temperatures force coral to expel the algae that lives inside it, causing the coral to turn white and making it more susceptible to disease.

"We've seen a couple of smaller bleachings at Scott Reef and now this very severe one again, so over 20 years I've largely watched the reef recover and now I've seen it impact again, and I wonder whether or not I'm going to see it recover in my lifetime," Gilmour said.

"We've been studying this for 20 years and we do know that coral bleaching is real and we do know that temperatures are rising, so what we need to is a consensus among everyone that this is a real pressure and we need to set about making all possible attempts to reduce the heating of the world's oceans."

Gilmour said the news was not entirely bad, with coral at Ashmore Reef, further east of Scott Reef, recovering almost entirely from the bleaching event.

Australia's iconic Great Barrier Reef has also been hit hard by coral bleaching with 22 percent of all coral on the reef killed by the bleaching event last summer. Endit