Sounds of the past give new hope for coral reef restoration

Young fish can be drawn to degraded coral reefs by loudspeakers playing the sounds of healthy reefs, according to new research published today [29 November] . An international team of scientists from the UK's Universities of Exeter and Bristol, and Australia's James Cook University and Australian Institute of Marine Science, say this "acoustic enrichment" could be a valuable tool in helping to restore damaged coral reefs. Working on Australia's recently devastated Great Barrier Reef, the scientists placed underwater loudspeakers playing healthy reef recordings in patches of dead coral and found twice as many fish arrived - and stayed - compared to equivalent patches where no sound was played. "Fish are crucial for coral reefs to function as healthy ecosystems," said lead author Tim Gordon , of the University of Exeter. "Boosting fish populations in this way could help to kick-start natural recovery processes, counteracting the damage we're seeing on many coral reefs around the world." This new technique works by regenerating the sounds that are lost when reefs are quietened by degradation. "Healthy coral reefs are remarkably noisy places - the crackle of snapping shrimp and the whoops and grunts of fish combine to form a dazzling biological soundscape. Juvenile fish home in on these sounds when they're looking for a place to settle," said senior author Professor Steve Simpson , also of the University of Exeter.