The Australian Great Barrier Reef, one of the most extraordinary and biodiverse ecosystems on the planet and a Unesco World Heritage Site, is dying slowly and inexorably. Thirty-five per cent of the corals that make up the reef have died as a result of bleaching caused by excessively high sea water temperatures, according to researchers at James Cook University.

The most severe condition ever recorded

The condition confirmed by researchers led by Professor Terry Hughes, through aerial and underwater surveys, is said to be the most severe ever recorded for the reef. The reef has lost around half of its coral cover over the past thirty years.

When the climate changes, corals die

The main threat to the Australian Great Barrier Reef is climate change. The warming of waters and the growing acidification of the oceans, combined with human impact and the invasion of a species of starfish that feeds on corals, are causing the degradation of one of the richest ecosystems on the planet. The rise in water temperature triggers what is known as coral bleaching, whereby corals fade and weaken the algae that supply them with oxygen and nutrients.

The death of an entire ecosystem

The death of the corals generates an inevitable cascade effect, with repercussions for the survival of all the other creatures that find shelter and sustenance in the reef, which stretches for 2,300 kilometres across an area of approximately 344,400 square kilometres off the coast of Queensland, in north-eastern Australia.

The southern section of the reef was saved by a cyclone

The majority of the southern section of the reef, south of Cairns, is said to have been spared from bleaching thanks to a violent tropical cyclone which, accompanied by heavy rainfall, cooled the waters.