For the first time, scientists have captured coral bleaching on video. The time-lapse footage reveals how corals inflate and contract to pump algae out when they are under stress. The new findings, published August 5 in the journal Coral Reefs, offer insights into how corals are responding to climate change.
Normally, corals live in harmony with algae called Symbiodinium, which are the source of their bright colors. In exchange for providing shelter, the corals feast on sugars created by their algal tenants. But as waters warm, the algae become toxic to their hosts. Coral bleaching happens when stressed corals expel their algae, leaving themselves pale and cut off from food.