Record die-off of Great Barrier Reef coral confirmed by scientists, while some tourist areas improved

Extract from ABC News

By Allyson Horn

Posted 36 minutes ago

Photo: Scientists assess coral mortality on Zenith Reef in the Great Barrier Reef's north. (Supplied: Andreas Dietzel, ARC Centre of Excellence for Coral Reef Studies)

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Map: Cairns 4870

Queensland scientists have confirmed this year's mass coral bleaching event has resulted in the largest die-off of corals ever recorded on the Great Barrier Reef, while some tourist areas showed remarkable improvement.

James Cook University researchers estimate two-thirds of coral coverage has died along a 700-kilometre stretch of reef off far north Queensland, north of Port Douglas.
While the northern reef struggled, there was good news for southern parts of the reef, which includes major tourist areas around Cairns and the Whitsundays.

Photo: The map details coral mortality, which varies from north to south. (Supplied: ARC Centre of Excellence for Coral Reef Studies)

JCU professor Terry Hughes said scientists had finished their underwater surveys, which they have been conducting since the severe coral bleaching event six months ago.
"When bleaching occurs, in the 6–12-month period afterwards, the corals either survive and regain their colour, or if they don't regain their colour, they slowly die," Professor Hughes said.
"So that's why we've had to wait seven or eight months before resurveying these reefs."
Professor Hughes described the area as severely damaged, and estimated it could take between 10 and 15 years for new corals to grow.

"A dead coral's not very spectacular, and many of them now are unrecognisable," he said.

"The bleaching in the northern section was so severe that corals that don't normally bleach, have.
"And so when you lose a 50-year-old coral, you can't [fix] it in just a handful of years."

Tourist areas show remarkable improvement

The researchers said it was not all doom and death for the World Heritage Area icon.
Surveys of southern areas, including peak tourists spots, showed a remarkable improvement in coral health and recovery.
"The good news is that south of Port Douglas, including the major tourists areas around Cairns and the Whitsundays, they have had relatively low levels of mortality," he said.

Photo: Dead table corals killed by bleaching in the northern section of the Great Barrier Reef. (Supplied: Greg Torda, ARC Centre of Excellence for Coral Reef Studies)

JCU researcher Andrew Baird said the latest survey was the final test to show the recovery of the areas.
But he will still be watching what happens this summer.
"We can't be complacent, and the big issue is, when is the next bleaching event," he said.
"Those reefs around Townsville and further south didn't bleach this year, hopefully they're not going to bleach next year.
"But who knows when the next major bleaching event will happen?"
The Great Barrier Reef Marine Park Authority said its experts would meet later this week to discuss whether this summer may see another bleaching event.
Mike Ball Dive Expeditions' tourist manager Craig Stephen said the researchers' findings offered some good news.
"It's escaped a lot of the bleaching that's occurred this year," he said.
"Unfortunately for us the majority of the diving and a majority of the tourists are coming to the northern section of the reef.
"Fortunately nonetheless, some patchy areas are unaffected so still world-class diving available."

Photo: Researcher Grace Frank surveying along through One Tree Reef and Capricorn Islands in the southern Great Barrier Reef. (Supplied: ARC Centre of Excellence for Coral Reef Stu