What happens when coral turns white
Bleaching is a stress response, not instant death. Understanding the difference explains why some reefs recover and others do not.
2 min read
When water stays too warm for too long, corals expel the algae living in their tissue. The algae give coral most of its colour, so without them the white skeleton shows through. That is bleaching.
A bleached coral is starving but not yet dead. If temperatures fall in time, the algae can return and the coral can recover. If the heat lasts, the coral dies and is gradually covered by other growth.
Reefs that are otherwise healthy, with clean water and plenty of grazing fish, tend to recover faster. Local care cannot stop ocean warming, but it can improve the odds.
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