The most pristine parts of the Great Barrier Reef are in the grip of the worst coral bleaching event in history, scientists say.
Experts who’ve surveyed 500 sites between Cairns and Papua New Guinea say once-healthy reefs are now snow-white, with the vast majority ranked in the most severe category of bleaching.
“Even more concerning, we haven’t yet found the southern limit of the bleaching,” says Professor Terry Hughes, the convenor of the National Coral Bleaching Taskforce.
He said the scale of reef damage was a very sad thing to witness.
“We flew for 4000km in the most pristine parts of the Great Barrier Reef and saw only four reefs that had no bleaching.”
The aerial surveys have confirmed the current bleaching event is far more severe than those of 2002 and 1998.
More aerial surveys are planned this week in the central Great Barrier Reef, to try to find the southern boundary of the bleaching.
But Professor Hughes said the southernmost stretches of the reef appeared to have dodged a bullet with cloudy weather keeping down water temperatures there.
Most of the reefs north of Cairns – a city that markets itself as the gateway to the Great Barrier Reef – are undergoing bleaching, and virtually all coral species, including the most robust types, have been affected.
Cape York residents have told surveyors they are shocked by what they’ve seen and they’ve never witnessed anything like it before.
WWF called on Prime Minister Malcolm Turnbull to travel to North Queensland to see the bleaching first-hand.
“When you look at those stark, white photos, you’re looking at the face of climate change,” spokesman Nick Heath said.
“We’ve been complacent on this issue for far too long. We can have our corals, or we can have our complacency.
“If we don’t start to see some real leadership on the Reef, it will be gone.”
The Australian Marine Conservation Society Great Barrier Reef campaign director, Imogen Zethoven, described the current bleaching as a “national environmental disaster”.
“Some of these corals are hundreds of years old. We are talking about hundreds of reefs being impacted by coral bleaching,” she said.
“The Reef is one of the wonders of the world. It is being ruined by global warming in front of our eyes.”
Professor Hughes said it was too early to say what the outcome for the reef would be, but scientists carrying out parallel surveys underwater were reporting half of all bleached corals are dead.
He said more surveys in coming months would reveal the full impact.
Read article at The Age