When a team of scientists listened to an audio clip recorded underwater off islands in central Indonesia, they heard what sounded like a campfire.

Instead, it was a coral reef, teeming with life, according to a study scientists from British and Indonesian universities published in June, in which they used hundreds of such audio clips to train a computer programme to monitor the health of a coral reef by listening to it.

A healthy reef has a complex “crackling, campfire-like” sound because of all the creatures living on and in it, while a degraded reef sounds more desolate, life sciences specialist and the team’s lead researcher Ben Williams said.

The artificial intelligence (AI) system parses data points such as the frequency and loudness of the sound from the audio clips, and can determine with at least 92% accuracy whether the reef is healthy or degraded, according to the team’s study published in Ecological Indicators journal.

The researchers hope to collect underwater recordings from reefs in Australia, Mexico and the Virgin Islands to help assess the progress of coral restoration projects. Long term it is hoped that this new AI system will help conservation groups around the world to track reef health more efficiently.

_{Image: A hydrophone that is used to recor underwater soundscape is placed on a reef in the sea of the Spermonde archipelago, South Sulawesi province, Indonesia, August 30, 2018. Tim Lamont/University of Exeter/Handout via REUTERS}