Coral bleaching is a stress-induced biological process in which reef-building scleractinian corals lose all or most of their endosymbiotic dinoflagellates (family Symbiodiniaceae) and/or their photosynthetic pigments, leading to visible paling or whitening of coral tissues. Triggered primarily by elevated sea surface temperatures, but also by light stress, pollution, or oxidative stress, bleaching involves disruption of the coral–algal symbiosis through mechanisms such as reactive oxygen species overproduction, damage to photosystem II, and activation of host cellular stress pathways that drive symbiont expulsion or degradation. Prolonged or repeated bleaching events impair coral metabolism, calcification, and reproduction, often increasing mortality and restructuring reef ecosystems.
The world's oceans absorbed a record amount of heat in 2025, an international team of scientists said Friday, further priming conditions for sea level rise, violent storms, and coral death.
Earth Sciences
Jan 9, 2026
1
420
Tropical coral reefs cover less than 1% of the seafloor, yet support 25% of all marine species. They are also incredibly vulnerable. Over the past few decades, an estimated 30–50% have already been lost.
Ecology
Jan 5, 2026
0
23
University of Sydney marine biologists have identified a devastating combination of coral bleaching and a rare necrotic wasting disease that wiped out large, long-lived corals on the Great Barrier Reef during the record 2024 ...
Plants & Animals
Dec 9, 2025
0
145
A global analysis of coral bleaching across 81 countries reveals that reefs in the equatorial Coral Triangle region were exposed to the weakest marine heat waves over the past two decades and may function as safe havens for ...
Plants & Animals
Nov 17, 2025
0
24
In early June 2023, the coral reefs in the lower Florida Keys and the Dry Tortugas were stunning. We were in diving gear, checking up on hundreds of corals we had transplanted as part of our experiments. The corals' classic ...
Ecology
Oct 25, 2025
0
42
New research reports the functional extinction of Acropora corals from Florida's Coral Reef. Scientists have documented catastrophic mortality of these critically endangered corals following a record-setting marine heat wave ...
Plants & Animals
Oct 23, 2025
0
251
The world's tropical coral reefs have almost certainly crossed a point of no return as oceans warm beyond a level most can survive, a major scientific report announced on Monday.
Ecology
Oct 13, 2025
0
31
The world faces a "new reality" as we have reached the first of many Earth system tipping points that will cause catastrophic harm unless humanity takes urgent action, according to a report released by the University of Exeter ...
Earth Sciences
Oct 12, 2025
2
70
A University of Hawai'i at Mānoa graduate's new research reveals that plastic pollution poses a significant, unseen threat to endangered coral reefs. The study found that chemicals leaching from plastics disrupt the two most ...
Plants & Animals
Oct 6, 2025
0
26
In a landmark effort to combat the devastating effects of climate change, a new global alliance with key leadership from the University of Hawaiʻi at Mānoa has been established to create a "Noahʻs Ark" for coral reefs.
Plants & Animals
Sep 25, 2025
0
22
