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Scientists have discovered that it's possible to hear the sound of coral reefs perishing.

At their brightest and most vibrant, coral reefs are among the noisiest environments on the planet and a healthy reef can be heard by sea creatures - and by humans using underwater microphones - from several miles away.

Now experts have recorded the more muted sound of a dying reef, as resident fish and crabs fight for their survival.

Scroll down for sound clips 

Scientists have recorded the more muted sound of a dying reef, as resident fish and crabs fight for their survival. A stock image of a reef suffering from acidification of the ocean is shown

Researchers from two British universities believe that human activities such as over-fishing drive away marine life so reefs are quieter.

This has a huge impact on the fish and invertebrates that rely on the underwater habitat for their home and food.

Dr Julius Piercy, from the University of Essex, led the study, which involved taking acoustic recordings of coral reefs with different levels of protection around islands in the Philippines.

The research found that the noise produced by the few remaining resident fish and crustaceans on unprotected reefs was only one third of that made from bustling, healthy reef communities. 

Scientists have discovered that it's possible to hear the sound of coral reefs dying. A clip of the sounds produced by residents of an ailing reef in the Philippines can be heard (above)

Bright and beautiful: At their brightest and most vibrant, coral reefs (stock picture) are among the noisiest environments on the planet and a healthy reef can be heard by sea creatures – and using underwater microphones – from several miles away

The level of noise is considered vital to the larval stages of reef fish and invertebrates, which spend the first few days of their life away from reefs and use sound as an orientation cue to find their way back.

With less sound being produced at impacted reefs, the distance over which larvae can detect habitat is ten times less.

This means that future generations could be affected, which are needed to build up and maintain healthy population levels.

Dr Piercy said: 'In an environment where underwater noise plays such an important role in the population dynamics of coral reefs, it is alarming to find such a large effect of human impact on the natural acoustic environment.

'This puts reef sound in the spotlight for the people who manage coral reef ecosystems because they might need to consider reef sound as an integral part of the design of marine protected area networks to ensure that there is sufficient recruitment of larvae and this study also shows sound can be useful in monitoring the health of coral reefs.'

'With growing evidence demonstrating the direct impacts of man-made noise on aquatic life, these findings highlight additional indirect human impacts, such as over-fishing and landscape development, on natural underwater sounds.

Dr Steve Simpson, of the University of Exeter, added: 'Taking sound recordings is a cheap, fast and objective way to get a broad idea of whether a reef is in a good condition or not.

Researchers from two universities believe that human activities such as over-fishing drive away marine life so reefs are quieter. The sound of a healthy reef can be heard above

'It can't replace detailed visual surveys conducted by snorkelers or divers but it gives a good account of the cryptic and nocturnal species missed in visual census and gives us a general picture of the state of coral reefs without the need for time-consuming surveys and extensive training.

'We still know very little about what sounds these animals are listening to and it is likely to be very different between species.

'Combined with recent findings that fish dislike the smell of impacted reefs there is a real need to understand how human impacts can indirectly affect the success of future generations of reef organisms.'  

Stunning time-lapse film shows life in a coral reef (Related)