Great Barrier grief: 91% bleached

A new report released quietly on Tuesday night reveals 91 per cent of the Great Barrier Reef experienced bleaching over summer.

Coral bleaching on Stanley Reef, Great Barrier Reef, March 23 2022. Picture: Harriet Spark

Ninety-one per cent of reefs surveyed on the Great Barrier Reef experienced bleaching over summer, according to a new report on the health of the 2200-km long natural wonder.

Of 719 reefs assessed from the air, 654 – or 91 per cent – showed signs of bleaching, the report from the Great Barrier Reef Marine Park Authority (GBRMPA) revealed.

The bleaching was most severe in the central part of the reef, although there were signs of variable damage in the northern and southern sections.

Last year was a period of relative recovery for the reef, with a lack of heatwaves and tropical cyclones, but waters heated considerably over summer, leading to the mass bleaching event, the fourth in the past seven years.

Of most concern to climate scientists is the fact the bleaching happened during a La Nina climatic period, usually associated with milder temperatures.

Coral bleaching on Stanley Reef, Great Barrier Reef, March 23 2022. Picture: Harriet Spark

Dr Simon Bradshaw, Director of Research at the Climate Council, said the report confirmed that the reef was “in serious trouble”.

“The Reef’s very survival, and all the jobs and industries that depend on it, requires a major step up on climate action now and during this next term of Government, starting with a credible plan to rapidly reduce Australia’s greenhouse gas emissions. Not 30 years from now, this decade,” Dr Bradshaw said.

“Climate change is front of mind for voters this election. They are counting on our next Federal Government to show true leadership. Australians deserve a government that will work hard to give our reef a fighting chance.”

Dr Simon Bradshaw from the Climate Council. Picture: Supplied

The GBRMPA report emphasised that bleached coral is “stressed but still alive” and said the bleaching event of 2020 actually led to “very low coral mortality“.

Another report on the health of the reef, using surface-level observation rather than aerial reconnaissance, is due in July or August from the Australian Institute of Marine Science.

A spokesperson for Environment Minister Sussan Ley said the report “underlies the importance of our $1 billion investment in additional protection for the Reef and our consistent position that global climate change is the biggest threat to reefs around the world”.

The government was investing in world leading science to help coral regrow and improve the resilience of the reef, the spokesperson said.

The government also shot down questions over the timing of the release of the report.

“The timing... was entirely a matter for the Reef agencies,” the spokesperson said. “No one in (the) government has influenced the release timing.”

Comment has been sought from the GBRMPA.

Originally published as Great Barrier grief: 91% bleached