Bleaching event

A bleaching event occurs when coral reefs lose their vibrant colors due to stress, primarily caused by unusually warm water temperatures. Corals have a special relationship with tiny algae called zooxanthellae that live inside their tissues, giving them color and providing essential nutrients through photosynthesis. When stressed by heat, corals expel these algae, losing their color and becoming pale or white—hence "bleached." This weakening process reduces their ability to survive and recover, making them more vulnerable to disease, starvation, and death, which can threaten entire reef ecosystems.