While the majority of the world’s reefs are now under threat or even damaged potentially beyond repair, a new study reported in the journal Current Biology on March 8 offers some encouraging news: efforts to restore coral reefs not only increase coral cover, but they can also bring back important ecosystem functions, and surprisingly fast.

“We found that restored coral reefs can grow at the same speed as healthy coral reefs just four years after coral transplantation,” says Ines Lange of University of Exeter, UK. “This means that they provide lots of habitat for marine life and efficiently protect the adjacent island from wave energy and erosion.”

“The speed of recovery that we saw was incredible,” she says. “We did not expect a full recovery of reef framework production after only four years.”

The work by Lange and her international colleagues represents the first reef carbonate budget trajectories at any coral restoration sites. The study was conducted at the Mars Coral Reef Restoration Program in South Sulawesi, Indonesia, one of the largest restoration projects in the world.