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.
The Great Barrier Reef has seen major bleaching in some of its sectors - particularly the more isolated, northern reef - and the expectation has long been that this event would result in significant coral death as well.
Now some of the first figures are coming in confirming that. Diving and aerial surveys of 84 reefs by scientists with the ARC Centre of Excellence for Coral Reef Studies at James Cook University, in Australia - the same researchers who recently documented at least some bleaching at 93 per cent of individual reefs - have found that a striking 35 per cent of corals have died in the northern and central sectors of the reef.