Study into noises that attract sharks

Researchers will compare shark behaviour when human noises were detectable to when they were masked.
Researchers will compare shark behaviour when human noises were detectable to when they were masked.

The project, led by Christine Erbe at Curtin’s Centre for Marine Science and Technology, will try to identify noises made by swimmers, surfers and kayakers that would attract large sharks.

Researchers will compare shark behaviour when human noises were detectable to when they were masked.

‘If we can successfully identify a difference in behaviour, masking sounds could be broadcast into the water by speakers along WA beaches or perhaps by the development of small, personal maskers that could be used by swimmers and other water users,’ Dr Erbe said.

‘There are already a number of approaches aimed at reducing shark attacks, such as the use of nets to keep sharks out of swimming areas and repelling sharks with deterrence devices.

‘But our approach is a little different, as it looks at interfering directly with the shark’s ability to detect humans.

‘We believe this approach is minimally invasive, will have minimum environmental impact and is the only long-lasting solution.

‘In contrast to deterrence devices, there is no risk of the sharks becoming accustomed to a stimulus and ceasing to respond to it.’ The team will record the noise of human activity at Perth beaches where shark encounters have occurred.

Researchers will then determine the sound cue of human activities that can be detected by sharks and design and compare two kinds of artificial signals ” one that mimics a typical beach environment and one that masks the sound detected by sharks.

‘It is likely that sound is the cue used most by sharks ” it is the only cue that travels fast and over long ranges underwater,’ Dr Erbe said.

‘Sound provides the most effective long-range stimulus in the marine environment, with most marine megafauna relying on sound for communication, navigation and foraging.’