Acoustic harassment device

Acoustic harassment and acoustic deterrents are technologies used to keep animals and in some cases humans away from an area. Applications of the technology are used to keep marine mammals away from aquaculture facilities and to keep birds away from certain areas (for instance in the vicinity of airports and blueberry fields). The devices have also been employed to keep marine mammals away from fishing nets. The devices are known as acoustic harassment devices (AHDs) and acoustic deterrent devices, which are smaller AHDs or intended as an awareness tool to warn species to the presence of danger rather than as a tool of harassment at a much louder level.

While they have proven effective over the short-term, animals tend to become conditioned over time and can even be drawn to the sounds once they habituate to the lack of real danger and the presence of sustenance. Only acoustic harassment devices that cause actual pain have been found to be effective over the longer term. The devices can cause hearing damage in non-targeted species and design changes in the fishing gear, fishing methods, and fish farm design to provide a permanent solution are preferable.