What Is Coral Bleaching And How Does It Happen?

What is coral bleaching?


Coral reefs are home to a diverse range of marine life and are important for the health of our oceans. However, in recent years, coral bleaching has become a major concern for scientists and environmentalists alike. But what exactly is coral bleaching, and how does it happen?

What is Coral Bleaching?

Coral bleaching is a process where coral loses its vibrant color and turns white. This happens when the coral expels the symbiotic algae that live inside it, which provide the coral with nutrients and energy through photosynthesis. Without these algae, the coral becomes stressed, weak, and vulnerable to disease.

What Causes Coral Bleaching?

There are several factors that can cause coral bleaching, including:

  • Changes in water temperature
  • Exposure to high levels of sunlight
  • Pollution
  • Overfishing

However, the primary cause of coral bleaching is climate change. As the temperature of the ocean rises, coral becomes stressed and expels its algae. This is why coral bleaching is most commonly seen in areas where the ocean is warming at a faster rate, such as the Great Barrier Reef in Australia.

The Process of Coral Bleaching

When coral is exposed to stressors such as changes in water temperature or pollution, it expels its algae. This causes the coral to turn white and become weak and vulnerable to disease. If the stressor is removed quickly enough, the coral may be able to recover and regain its color. However, if the stressor continues or worsens, the coral may die.

The Impact of Coral Bleaching

Coral bleaching has a major impact on marine ecosystems. Without healthy coral reefs, many species of marine life are at risk of extinction. Coral reefs also provide important protection for coastlines from storms and erosion. Additionally, coral reefs are a major source of income for many coastal communities through tourism and fishing.

What Can We Do to Help?

While the primary cause of coral bleaching is climate change, there are still things we can do to help protect coral reefs. These include:

  • Reducing our carbon footprint by using renewable energy and reducing our use of fossil fuels
  • Reducing pollution by using eco-friendly products and properly disposing of waste
  • Supporting conservation efforts and organizations that work to protect coral reefs
  • Advocating for policies and legislation that protect coral reefs


Coral bleaching is a major threat to the health of our oceans and the species that call them home. While the primary cause is climate change, there are still things we can do to help protect coral reefs and the marine life that depend on them. By taking action now, we can help ensure that coral reefs continue to thrive for generations to come.