Great Barrier Reef

Why in news?

• Coral has recovered from storms and bleaching events to record levels across much of Australia's Great Barrier Reef, a survey has found.
• The reef's northern and central parts have the highest amount of coral cover since monitoring began 36 years ago.

About Great Barrier Reef:

• The Great Barrier Reef is located on the north-east coast of Australia (Coral Sea).
• It contains the world’s largest collection of coral reefs, with 400 types of coral, 1,500 species of fish and 4,000 types of mollusc.
• It is the world's biggest single structure made by living organisms.
• This reef structure is composed of and built by billions of tiny organisms, known as coral polyps.
• It supports a wide diversity of life and was selected as a World Heritage Site.
• It also holds great scientific interest as the habitat of species such as the dugong (‘sea cow’) and the large green turtle, which are threatened with extinction.

What is Coral Bleaching?

• Coral reefs originate from a symbiotic relationship between the coral polyps and algae that live in the polyps.
• Coral bleaching occurs when the coral polyps expel these algae.
• They occur due to factors such as variations in water temperature, acidity & salinity, extreme low tides, sea level rise, excessive sedimentation, zoonotic diseases, cyanide fishing and pollution.
• When coral bleach occurs, it is not dead. Corals can survive a bleaching event. But as they come under more stress, they are subject to mortality.

PRACTICE QUESTION

Great Barrier Reef is located in which of the following sea?

(a) Bering Sea

(b) Coral Sea

(c) Tasman Sea

(d) Yellow Sea

Answer