A coral the size of a carousel is the widest known in the Great Barrier Reef.
Found just off the coast of Goolboodi Island in Northeast Australia, this reef-building Porites measures 10.4 meters in diameter — earning it the nickname Muga dhambi, or “big coral,” from the Indigenous custodians of the island, the Manbarra people.
In addition to its record-setting width, Muga dhambi stands a little over 5 meters tall, making it the sixth tallest coral in the Great Barrier Reef, researchers report August 19 in Scientific Reports.
“It’s a stand-alone coral … and we don’t see many that size,” says marine scientist Nathan Cook of Reef Ecologic, a climate and environmental consulting firm in Townsville, Australia.
Based on Muga dhambi’s height and estimated growth rate, Cook and colleagues calculate that the creamy brown, boulderlike coral is about 421 to 438 years old. It predates European colonization of Australia and has survived as many as 80 cyclones (SN: 5/28/20) and 99 coral bleaching events (SN: 7/4/21), the team says.
Many of the recent stories about corals in the Great Barrier Reef read like obituaries, Cook says. “Knowing that these things [like Muga dhambi] exist, and have persisted for a long time, helps to provide a renewed sense of hope for the future.”

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