Acoustic deterrent system A-ASR®

fishfor aquaculture

The A-ASR® devices are designed to protect farmed fish from predators without harming marine mammals. They target marine predators, such as seals and sea lions, but avoid the specialised hearing ranges of dolphins and porpoises. A triggered mechanism produces a low-frequency sound to startle any predators. It delivers randomised frequencies and tonal patterns to prevent seals and sea lions from becoming accustomed to the sounds. The signal requires less acoustic output into the water than older-generation barrier systems. It takes only ten milliseconds from the start of the noise to reach its peak to create a physical response in marine mammals which they cannot ignore.