Great Barrier Reef Lost Half of Coral Cover Since 1985, Study Says


The Great Barrier Reef has lost half of its coral cover in just 27 years, with most of that decline coming as a result of heavy storms, predation by crown-of-thorn starfish, and coral bleaching caused by warming ocean temperatures.

In a comprehensive survey of 214 reefs, researchers at the Australian Institute of Marine Science (AIMS) found that coral cover declined from 28 percent in 1985 to 13.8 percent this year.

Intense tropical storms, particularly in the central and southern parts of the reef, have caused about 48 percent of the coral loss, researchers say. An explosion in populations of starfish along the entire reef caused about 42 percent of the decline; about 10 percent was caused by major bleaching events.

Reefs are typically able to regain their coral cover after such disturbances, said Hugh Sweatman, one of the lead authors of the study, published in the Proceedings of the National Academy of Sciences. “But recovery takes 10-20 years,” Sweatman said.

“At present, the intervals between the disturbances are generally too short for full recovery and that’s causing the long-term losses.” While the scientists say little can be done about the storms, the study found that efforts to reduce starfish populations could help increase coral cover at a rate of 0.89 percent per year.

Article appearing courtesy Yale Environment 360.

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Yale Environment 360 is an online magazine offering opinion, analysis, reporting and debate on global environmental issues. We feature original articles by scientists, journalists, environmentalists, academics, policy makers, and business people, as well as multimedia content and a daily digest of major environmental news. Yale Environment 360 is published by the Yale School of Forestry & Environmental Studies and Yale University. We are funded in part by the Gordon and Betty Moore Foundation and by the John D. and Catherine T. MacArthur Foundation. The opinions and views expressed in Yale Environment 360 are those of the authors and not of the Yale School of Forestry & Environmental Studies or of Yale University.

1 Comment

  1. Thank you for this important article. I first read about this perhaps shortly after returning to Japan from a holiday in Oz. It half destroyed me. But I think I’m a pretty resilient kind of person, who can afford to be aake and aware. I have started a positive social media campaign called Get Yourself a Paper Cup at If you like its properties or at least some of its ideas, please let me know or simply share this information in the best way you know how. The people of Queensland, I think, are not going to sleep on this one. I hope not anyway. I am trying to raise some money for Australian scientists. Please help me do so.