Coral Bleaching

Coral reefs are bright and beautiful homes in the ocean. But sometimes corals lose their color and turn white. This is called coral bleaching. It happens when the water gets too warm or dirty. Bleached coral is sick and can die if things do not get better.

Why It Happens

Corals share their home with tiny plants called algae. The algae give coral food and color. When the water gets too hot, coral pushes out the algae. Then the coral turns white and starts to starve. Pollution and sunlight can also cause bleaching.

Bright green fish swim above healthy, colorful coral.
Bright green fish swim above healthy, colorful coral. (Holobionics / Wikimedia Commons)

How to Help

People help by keeping the ocean clean. They pick up trash from beaches and cut down on pollution. Scientists try to grow new coral in special labs. Using less energy at home can help slow climate change. Healthy oceans mean healthy coral.

Fun Facts

  • Coral reefs take up less than 1% of the ocean but are home to 25% of sea animals.
  • The Great Barrier Reef in Australia is the biggest coral reef on Earth.
  • Some coral can live for hundreds of years if they stay healthy.

Did You Know?

Coral is actually an animal, not a plant. It is related to jellyfish and sea anemones.