Understanding Coral Bleaching

Coral reefs are often called the rainforests of the sea because they support a vast number of marine species, despite covering less than one percent of the ocean floor. These vibrant ecosystems are built by tiny marine animals called coral polyps. Corals have a special partnership with microscopic algae called zooxanthellae that live inside their tissues. The algae use photosynthesis to produce food and energy for the corals, while the corals provide the algae with shelter. This relationship also gives corals their beautiful, bright colors. However, coral reefs are under severe threat from climate change. When ocean temperatures rise even slightly, corals become stressed. In response, they expel the algae living inside their tissues. Without the algae, the corals lose their primary food source and turn completely white. This process is known as coral bleaching. Bleached corals are not dead, but they are weak and highly susceptible to disease. If the water temperature returns to normal quickly, the algae can return and the corals can recover. However, if the heat stress continues for too long, the corals starve and die, leaving behind a lifeless gray skeleton. The loss of coral reefs would have devastating consequences for marine life, coastal communities that depend on fishing, and tourism industries worldwide, making ocean protection an urgent global priority.