Mass bleaching in Great Barrier Reef

• A “mass bleaching event” is unfolding on Australia’s famed Great Barrier Reef, authorities said recently, as warming seas threaten the spectacular home to thousands of marine species.
• The damaging mass bleaching event — the seventh since 1998 — was confirmed by government scientists following aerial surveys of 300 shallow reefs.
• Before this event, Australia’s Great Barrier Reef suffered mass coral bleaching in 1998, 2002, 2016, 2017, 2020 and 2022.
• The World Heritage Committee has considered to put the reef on a list of “in danger” global heritage sites

ABOUT GBR

• Often dubbed as the world’s largest living structure, the Great Barrier Reef is a 2,300 km (1,400 mile) expanse of tropical corals that house a stunning array of biodiversity.
• It is made up of around 3,000 individual reefs and reef structure is composed of and built by billions of tiny organisms, known as coral polyps.
• It was declared a World Heritage Site in 1981.

ABOUT CORAL BLEACHING

• Coral bleaching occurs when underwater temperatures are more than one degree warmer than the long-term average.
• As corals come under heat stress, they expel algae living within their tissues — draining them of their vibrant colours.
• Corals have the ability to recover, depending on the intensity of heat stress and its duration. However, prolonged or intense heat can prove fatal to corals.