Widespread bleaching during the cooler temperatures of La Niña has left scientists dreading the damage that could be caused by the next El Niño
Through a snorkel mask, the corals struggling for survival in the heat are easy to spot. Some have turned white while others are pouring out a fluorescent pigment into their flesh – it’s spectacular, but it’s also a sign of a coral in deep distress.
This is John Brewer Reef about 70km off Townsville in Queensland – the centre of a widespread coral bleaching event. For hundreds of kilometres in either direction, reefs are going through the same battle.