Bleached staghorn coral on the Great Barrier Reef between Townsville and Cairns, March 2017BETTE WILLIS, ARC CENTRE OF EXCELLENCE FOR CORAL REEF STUDIES
Australia’s Great Barrier Reef is undergoing its third mass bleaching episode, which began in 2016. These events, which are spurred by warming waters, pose a dire threat to coral life, researchers reported Wednesday (March 15) in Nature.
When ocean waters warm, coral start to expel photosynthetic algae, a major energy source for the animal colonies. Such algal loss is known as bleaching, as it leaves the reefs an eerie white. If the waters cool, the polyps can recover their algae; otherwise, they will starve and die.
“If you think about it, on a really hot day, it’s hot out, it’s not a big deal. But when it goes on and on through time, that’s when people without air conditioning start dying,” Mark Eakin, a coral ...
