How a Healthy Coral Can Help a Bleached One Recover

Scientists at Stanford found that bleached corals can recover quickly when they touch healthy pieces from the same coral. In a lab experiment, researchers put small branches of the coral Pocillopora damicornis together. A bleached branch that touched a healthy one began to regain colour in just a few days.

The healthy coral sent tiny algae into the bleached coral through a tissue bridge. After about one week of contact, the bleached pieces continued to recover on their own and were fully healthy in seven weeks. Fragments that did not touch a healthy piece often died. This work offers hope, but it was tested in tanks and not yet in natural reefs.