Definition of 'Acoustic harassment devices'

Devices that emit sounds of such high intensity that they cause pain or alarm in certain underwater species. The minimum sound level is approximately 200 dB re 1 _Pa @ 1m. References for AHDs primarily dealt with aquaculture operations. These devices may exclude some animals from important habitat (Olesiuk et al., 2002), and pose a risk of impairing an animal’s hearing. These drawbacks render this approach potentially harmful and dangerous.