Media Release
28 February 2024
Aerial surveys confirm extent of bleaching on southern Great Barrier Reef
Helicopter flights over the southern Great Barrer Reef have confirmed extensive coral bleaching across the region.
Great Barrier Reef Marine Park Authority (Reef Authority) staff together with scientists from the Australian Institute of Marine Science (AIMS) took to the skies over the weekend to survey 27 inshore reefs in the Keppel Islands and Gladstone region and 21 offshore reefs in the Capricorn Bunkers.
Reef Authority Director for Reef Health, Dr Mark Read, said coral bleaching was extensive and fairly uniform across all surveyed reefs, with bleaching detected down to the visible depths in clear water across most locations, aligning with observations of accumulated heat stress.
“In the reef communities surveyed most coral cover displayed some level of bleaching with white and fluorescent colonies observed in shallow reef areas,” he said.
AIMS Senior research scientist, Dr Neal Cantin said, calm conditions across the region provided good visibility.
“We were able to see bleached corals at depth quite clearly across the reef slope from the air,” he said.
“Limited bleaching was observed on some reefs north of Mackay and into the Whitsunday Islands during additional surveys.
“Aerial surveys are an ideal tool to assess the spatial extent of bleaching, but we need to go under the water to understand more about the severity of bleaching and how deep the bleaching extends,” Dr Cantin said.
Over the next three to four weeks, teams of scientists and managers will continue to carry out these in-water surveys across the Great Barrier Reef.
While the southern Great Barrier Reef appears to be most affected by coral bleaching, the Reef Authority has received reports of bleaching from all other regions of the Reef.
“We will work with our Reef Joint Field Management Program compliance officers to undertake further helicopter surveys over the southern reefs this coming weekend,” Dr Read added.
“We are also preparing for broadscale surveys by fixed wing aircraft which will cover the central and northern regions, should conditions indicate these are required. These would be timed to optimise the peak of heat stress to provide us with the best understanding of the event’s extent and severity.
The Reef Authority works with its partners to monitor Reef health year-round but steps up activity during the high-risk summer months when impacts such as cyclones, floods and elevated water temperatures are more prevalent.
Bleaching is a stress response by coral and can show up in different ways — from paling in corals, to fluorescent colours and bleached fully white. In most cases corals can recover from bleaching, but in severe cases, they can die. However, with the right conditions, even severely bleached reefs can recover.
Dr Read reminded Reef users that everyone can do their bit to protect this spectacular marine ecosystem by following the rules when out in the Marine Park.
“Know the zones that you can fish in, don’t anchor on coral, and take home your rubbish when out in the Marine Park. Most importantly do what you can to contribute to the global effort to reduce greenhouse gas emissions.”
ENDS
Contact:
Reef Authority Media
Great Barrier Reef Marine Park Authority
P: (07) 4750 0846
E: media@gbrmpa.gov.au