Coral bleaching: Quick Facts

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Last updated

Oct. 26, 2026

News •

Filming coral bleaching at an unprecedented level • Oct. 22, 2026, 6:13 AM ET (BBC)

Stanford Scientists Discover a Remarkable Way To Rescue Dying Corals in Just Seven Weeks • Oct. 21, 2026, 11:54 AM ET (SciTechDaily)

A simple touch can bring dying corals back to life in just 7 weeks • Oct. 17, 2026, 3:00 AM ET (Science Daily)

Better together? Coral fusion could throw bleached reefs a lifeline • Oct. 15, 2026, 3:20 PM ET (Phys.org)

Facts

Also Known As	bleaching

Photos and Videos

Underwater view of a shallow coral reef off Guam showing widespread coral bleaching, with many corals appearing white and lacking vibrant color.

A bright orange starfish rests on top of bleached coral in a coral reef, with various fish and yellow coral visible in the background off the coast of Costa Rica.

Map of Australia's Great Barrier Reef showing areas most severely affected by coral bleaching in 2016, 2017, and 2020, marked in orange, pink, and purple along the reef's length. An infographic on the right illustrates four stages of coral bleaching: healthy coral with symbiotic algae, coral under stress as algae depart, bleached coral with a white skeleton, and coral death with other algae species encrusting the skeleton.

Close-up of coral reef at Apo Reef, Occidental Mindoro, showing large patches of white bleached coral alongside areas of healthy brown coral.

World map highlighting the locations of the most endangered coral reefs, shown in pink along tropical and subtropical coastlines. Notable concentrations appear in the Caribbean Sea, eastern coast of Central America, eastern Africa, the Red Sea, South and Southeast Asia, the South Philippine Sea, and around northern Australia and the South Pacific islands.

bleached coral seascape

What causes coral bleaching on the Great Barrier Reef?

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Topics

How and Where Coral Bleaching Is Affecting the Great Barrier Reef Coral Bleaching: A Threat to Our Reefs Marine ecosystem coral reef coral aquatic ecosystem eutrophication Water bloom biochemical oxygen demand Inland water ecosystem 14 Questions About Aquatic Animals Answered Boundary ecosystem pelagic zone

Chutes d'Ekom - a waterfall on the Nkam river in the rainforest near Melong, in the western highlands of Cameroon in Africa.

Ecosystems