#$%^&*AU2013204487B220161110.pdf#####26 Abstract Disclosed is a method of deterring mammals, and in particular sea lions, comprising configuring an acoustic deterrent system to emit an acoustic 5 signal having characteristics which cause said mammals to be repelled from an area. The method comprises eliciting an acoustic startle response reflex in said mammals by emitting an acoustic signal which has an envelope with a slope of at least 0.8 dB /ms. The acoustic signal may also span a frequency band having a lower limit greater than 2kHz. 101/2 12 18 16 Fig. 1 0.6 pain perception, y = x 0.6 3 -loudness, y = x E 012 4 0 1 2 3 4 5 magnitude of physical stimulus Fig. 2
