PETER MICHAEL, The Courier-Mail 22 Aug 16;
REEF tourism operators have found less than five per cent of coral has died off — compared to the 50 to 60 per cent estimated by scientists — under “extreme” mass coral bleaching on the northern Great Barrier Reef.
Latest findings exclusively obtained by The Courier-Mail show coral mortality in the outer shelf reefs north of Lizard Island was between one and five per cent with “spectacular” fish life and coral coverage.
Teams of divers in a joint two-week expedition sponsored by Mike Ball Dive and Spirit of Freedom surveyed 28 sites on 24 outer shelf reefs along a 300km section of the hardest-hit part of the reef from Bathurst Head to Raine Island.
Spirit of Freedom owner Chris Eade said reports of 93 per cent bleaching on the 2300km long Great Barrier Reef had made global headlines and damaged the reputation of the $5 billion reef tourism industry.
“Scientists had written off that entire northern section as a complete white-out,’’ Mr Eade said.
“We expected the worst. But it is tremendous condition, most of it is pristine, the rest is in full recovery.
“It shows the resilience of the reef.’’
Mike Ball Dive Expeditions operations manager Craig Stephen, who conducted a similar survey on the remote reefs 20 years ago, said there had been almost no change in two decades despite the latest coral bleaching event.
“It wasn’t until we got underwater that we could get a true picture of what percentage of reef was bleached,’’ Mr Stephen said.
“The discrepancy is phenomenal. It is so wrong. Everywhere we have been we have found healthy reefs.
“There has been a great disservice to the Great Barrier Reef and tourism and it has not been good for our industry.”
The Great Barrier Reef Marine Park Authority estimated a mass coral white-out of between 50 to 60 per cent, on average, for reefs off Cape York under the world’s biggest-ever mass coral bleaching event.
Scientists with the Townsville-based ARC Centre of Excellence for Coral Reef Studies reported about 35 per cent mortality but warned “the final death toll” on some reefs may exceed 90 per cent.
In April, aerial and underwater surveys of 522 reefs in the northern sector showed 81 per cent had been severely bleached and one per cent not bleached.
Professor Terry Hughes, convener of the National Coral Bleaching Taskforce, at the time said “it’s like 10 cyclones have come ashore all at once.”
Professor Hughes yesterday welcomed the positive news but had not yet seen the latest survey findings.
“We won’t know the true coral mortality until we can get back up there in October and compare before and after impacts from our March survey,’’ Prof Hughes said.
“Those coral will either survive or more will die.’’
A GBRMPA spokeswoman said they would closely examine the findings of the first independent expedition into the isolated region.
“Obviously if they’ve found reefs with a lower than expected mortality rate that is fabulous news,’’ she said.
“Our initial findings noted that the level of bleaching and mortality was expected to be very variable across the entire reef system.’’
