Summary
Preliminary field studies were carried out on a potentially cetacean-friendly acoustic deterrent system for seals (played using underwater loudspeakers). The “smart seal deterrent signal” produces a startle response in seals rather than an aversion to a very loud noise, and is transmitted at a sound level which is not harmful to seals, even at very close distances. There was some evidence that the acoustic deterrent was effective at deterring gray seals (Halichoerus grypus) from fishing operations, although there was a low seal interaction rate regardless of whether the device was on or not.