The Great Barrier Reef is amidst its fifth widespread coral bleaching event in just eight years, aerial surveys have revealed.
The surveys, conducted by the Great Barrier Reef Marine Park Authority and the Australian Institute of Marine Science (AIMS), observed over 300 reefs between Cape Melville north of Cooktown to just north of Bundaberg and confirmed the event.
Reef Authority Chief Scientist Dr Roger Beeden said the results of these surveys are consistent with the patterns of heat stress that have built up over summer.
“The results are consistent with what we have seen with above average sea surface temperatures across the Marine Park for an extended period of time,” Dr Beeden said.
“Aerial surveys of the Reef have revealed prevalent shallow water coral bleaching on most surveyed reefs.
“It is important to note, that the heat stress has not been even across the Reef, and the coral bleaching observed is variable.
“Monitoring the health of the Reef is a year-round effort for the Reef Authority, and it’s critical for us to understand what is happening on the Reef so we can target our management actions to protect the Reef and strengthen its resilience.
“Climate change is the greatest threat to the Great Barrier Reef, and coral reefs globally.”
AIMS Senior Research Scientist Dr Neal Cantin said that the aerial surveys provide a visual indication of the extent of bleaching.
However, assessing the severity to coral colonies requires in-water surveys.
“Aerial surveys are a crucial tool for a reef ecosystem as large as the Great Barrier Reef and show that this coral bleaching event is widespread, or what is commonly called a mass coral bleaching event,” Dr Cantin said.
“We now need to combine the spatial coverage captured from the air with in-water surveys to assess the severity of coral bleaching in deeper reef habitats across the different regions of the Marine Park.
“We will continue to conduct in-water observations with our research teams and management partners.”
The Reef Authority will continue to work closely with research and other science partners, Traditional Owners, and the tourism industry to monitor conditions on the Reef.
