There is understandably a widespread apprehension of sharks and the possibility of shark attack, despite the relatively low incidence of attacks. Abundant evidence indicates that apprehension, even in the absence of a shark sighting, has an adverse effect on performance, whether in a survival situation or in the execution of an operational task. (p. 29)
Despite over 70 years of research on shark repellents, few practical and reliable solutions to prevent shark attacks on humans or reduce shark by catch and depredation in commercial fisheries have been developed. In large part, this deficiency stems from a lack of fundamental knowledge of the sensory cues that drive predatory behavior in sharks.