“Parts of the Great Barrier Reef are enduring sustained periods of heat stress worse than at the same time during last year's record-breaking coral bleaching event, raising fears the natural wonder may suffer another hammering.”
Parts of the Great Barrier Reef are enduring sustained periods of heat stress worse than at the same time during last year's record-breaking coral bleaching event, raising fears the natural wonder may suffer another hammering. Some 54 checks by the reef's Marine Park Authority off Mission Beach, about midway between Cairns and Townsville, found 60 per cent of sensitive coral species were already bleaching after 12 months of sustained abnormally warm temperatures. "There's enough bleaching there to tell us that it is a significant heat-stress event," Russell Reichelt, the authority's chairman, said. "There's the risk there of widespread bleaching leading to further mortality." The World Heritage-listed reef last year suffered its worst bleaching event on record, with northern regions losing as much as 80 per cent of corals. Many of the big tourist sites were spared the worst of the bleaching or recovered quickly, but this year the heat stress is closer to Cairns and other popular sites. "It's the first time we've been getting a big bleaching event two years in a row," said Richard Fitzpatrick, an Emmy Award-winning underwater cameraman, who recently returned from Vlasoff Reef, north-east of Cairns. The bleaching is evident at places where Mr Fitzpatrick filmed sequences for the Great Barrier Reef series led by David Attenborough, the UK naturalist. "We've started to see the first mortality," Mr Fitzpatrick said. If waters stay too warm for too long, corals expel the zooxanthellae algae living in their tissues that provide as much as 90 per cent of the energy they need to grow and reproduce. The corals then bleach and face increased risks of disease, and those that survive can take years to recover.