Australia’s Great Barrier Reef suffers worst bleaching on record

The 2,300km (1,429-mile) reef is in its fifth mass bleaching event since 2016 with aerial surveys showing the scale of damage.

Australia’s Great Barrier Reef, which stretches for some 2,300km (1,429 miles) off the country’s northeastern coast, is suffering its worst bleaching event on record.

The extent of the bleaching was revealed in aerial surveys after the government agency tasked with the reef’s management confirmed early last month that the reef had been hit by its fifth major bleaching event since 2016.

The bleaching, when corals expel the colourful microscopic algae that live in their tissues in an effort to survive, was triggered by an increase in water temperatures that began in December last year.

“This prolonged heat exposure has caused mass bleaching of coral reef communities observed within all three regions of the Great Barrier Reef,” the Great Barrier Reef Marine Park Authority said in an update on its website on Wednesday. “The combination of aerial and in-water surveys in 2024 confirm a mass bleaching event, with prevalent and extreme bleaching observed at multiple reefs in all 3 regions of the Great Barrier Reef Marine Park.”

The agency said it surveyed a total of 1,080 reefs and 79 percent of them showed some level of coral bleaching. Some 49 percent of surveyed reefs showed high to extreme levels of bleaching, it said, with the worst-affected areas in the central and southern parts of the World Heritage-listed reef.