We knew this was coming. For months, coral reef experts have been loudly, and sometimes mournfully, announcing that much of the treasured Great Barrier Reef has been hit by “severe” coral bleaching, thanks to abnormally warm ocean waters. Bleaching, though, isn’t the same as coral death. When symbiotic algae leave corals’ bodies and the animals then turn white or “bleach,” they can still bounce back if environmental conditions improve.