Is coral bleaching a natural process?
Coral bleaching is a stress response and individual coral colonies will suffer from a degree of bleaching in any given summer. This is a natural process and not of particular concern.
What is coral bleaching and why is it bad?
Coral bleaching occurs when corals are stressed by changes in environmental conditions such as temperature, light or nutrients. The coral expels the symbiotic algae living in its tissue, causing the tissue to turn white or pale.
What happens when coral is bleached?
Coral bleaching happens when corals lose their vibrant colors and turn white. But there’s a lot more to it than that. Coral are bright and colorful because of microscopic algae called zooxanthellae. The zooxanthellae live within the coral in a mutually beneficial relationship, each helping the other survive.
Is coral bleaching caused by bleach?
Mass bleaching occurs when a wide range of coral species bleach over a large area of reef. The most common cause is elevated water temperatures in conjunction with increased ultraviolet radiation due to calm weather and clear skies.
What human activities cause coral bleaching?
Increased greenhouse gases from activities like deforestation, and the burning of fossil fuels for heat and energy, cause ocean temperatures to rise, change storm patterns, and contribute to sea level rise. These changes lead to more coral bleaching events, increased storm destruction, and more.
Where does coral bleaching occur?
the Great Barrier Reef
Iconic reefs such as the Great Barrier Reef in Australia and the Northwestern Hawaiian Islands in the United States have all experienced their worst bleaching on record with devastating effects. The bleaching of the Great Barrier Reef in 2016 and 2017, for instance, killed around 50% of its corals.
Is coral bleaching bad for the environment?
As the Earth’s temperature warms due to global warming – so does the risk of mass bleaching – as seas get warmer. Coral bleaching can be devastating – it has the potential to wipe out whole ecosystems – as wildlife around the coral can no longer find food, they move away or die, creating barren underwater landscapes.
Why does coral bleaching occur?
Coral bleaching occurs when corals are stressed by a change in environmental conditions. They react by expelling the symbiotic algae that live in their tissues and then turn completely white. The symbiotic algae, called zooxanthellae, are photosynthetic and provide their host coral with food in return for protection.
What is a direct cause of coral bleaching?
The main cause of coral bleaching is heat stress resulting from high sea temperatures. Temperature increases of only one degree celsius for only four weeks can trigger bleaching events. If this temperatures persist longer periods (eight weeks or more) corals begin to die.
Is coral bleaching caused by humans?
How do humans impact the coral reefs?
Pollution, overfishing, destructive fishing practices using dynamite or cyanide, collecting live corals for the aquarium market, mining coral for building materials, and a warming climate are some of the many ways that people damage reefs all around the world every day.