|Great Barrier Reef Shows Highest Coral Cover in 36 Years Great Barrier Reef now have the highest levels of coral cover seen in decades.
Amazing News! The Great Barrier Reef Just Made a Massive Comeback
Two-thirds of the Great Barrier Reef in Australia recorded the highest amount of coral cover in nearly four decades, though the reef is still vulnerable to climate change and mass bleaching, a monitoring group said Thursday.
The northern and central parts of the UNESCO world heritage-listed reef have experienced some recovery while the southern region has seen a loss of coral cover due to crown-of-thorns starfish outbreaks, according to a report by the Australian Institute of Marine Science, a government agency.
AIMS CEO Paul Hardisty said that while the coral in the north and central regions was a sign the reef could recover from disturbances, the loss of coral in the southern region demonstrated how the reef is still vulnerable to “continued acute and severe disturbances that are occurring more often and are longer-lasting.”
The Great Barrier Reef has suffered from widespread and severe bleaching because of rising ocean temperatures. The reef was hit especially hard in 2016 and 2017 by underwater heat waves that prompted bleaching events. This year, it’s suffering a sixth mass bleaching due to heat stress caused by climate change.
“Every summer the Reef is at risk of temperature stress, bleaching and potentially mortality and our understanding of how the ecosystem responds to that is still developing,” Hardisty said in a media release.
“The 2020 and 2022 bleaching events, while extensive, didn’t reach the intensity of the 2016 and 2017 events and, as a result, we have seen less mortality,” Hardisty said. “These latest results demonstrate the Reef can still recover in periods free of intense disturbances.”
Parts of the Great Barrier Reef have recorded their highest amount of coral cover since the Australian Institute of Marine Science (AIMS) began monitoring 36 years ago, according to a report published Thursday.
An AIMS survey of 87 reefs found that between August 2021 and May 2022, average hard coral cover in the upper region and central areas of the reef increased by around one third.
It's a rare piece of good news for the world-famous reef, which in March underwent its sixth mass bleaching event.
AIMS CEO Dr. Paul Hardisty said the results in the north and central regions were a sign the reef could still recover from mass bleaching and outbreaks of crown-of-thorns starfish that feed on coral.
However, he emphasized that the loss of coral cover elsewhere in the reef suggests it is still susceptible to threats, like marine heatwaves. The report added that due to climate change, these disturbances that could reverse the progress in coral growth were likely to become more frequent and longer lasting.
AIMS monitoring program team leader Dr. Mike Emslie said that most of the increase was driven by fast-growing Acropora corals which are "particularly vulnerable" to coral bleaching, wave damage caused by tropical cyclones and as prey for the starfish.
"This means that large increases in hard coral cover can quickly be negated by disturbances on reefs where Acropora corals predominate," Emslie said.
The Australian Marine Conservation Society's Great Barrier Reef Campaigner Cherry Muddle cautioned that while the report was a sign of progress, the reef remains at risk.
"While this growth is positive and shows the reef is dynamic and can be resilient, it doesn't discount the fact that the reef is under threat," Muddle said.