‘Mass bleaching’ at Great Barrier Reef

Australia's spectacular Great Barrier Reef is suffering "mass bleaching" as corals lose their colour under the stress of warmer seas, authorities said yesterday, in a blow widely blamed on climate change. The world's largest coral reef system, stretching for more than 2,300 kilometres along the northeast coast of Australia, is showing the harmful effects of the heat, said the Reef Authority. Aerial surveys detected coral bleaching at multiple reefs across a large area of the system, "confirming a mass bleaching event, the fourth since 2016," it said in a report. The Great Barrier Reef, home to some 1,500 species of fish and 4,000 types of mollusc, was suffering despite the cooling effect of the La Nina weather phenomenon. The area, which comprises about 2,500 individual reefs and more than 900 islands, suffers from bleaching when corals expel algae living in their tissues, draining them of their vibrant colours. Though bleached corals are under stress, they can still recover if conditions become more moderate, the Reef Authority said.