How Close is too Close? The Effect of a Non-Lethal Electric Shark Deterrent on White Shark Behaviour

dc.contributor.authorKempster, R
dc.contributor.authorEgeberg, C
dc.contributor.authorHart, N
dc.contributor.authorRyan, l
dc.contributor.authorChapuis, L
dc.contributor.authorKer, C
dc.contributor.authorSchmidt, C
dc.contributor.authorHuveneers, Charlie
dc.contributor.authorGennari, E
dc.contributor.authorYopak, K
dc.contributor.authorMeeuwig, J
dc.contributor.authorCllin, S
dc.descriptionThis is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.en
dc.description.abstractSharks play a vital role in the health of marine ecosystems, but the potential threat that sharks pose to humans is a reminder of our vulnerability when entering the ocean. Personal shark deterrents are being marketed as the solution to mitigate the threat that sharks pose. However, the effectiveness claims of many personal deterrents are based on our knowledge of shark sensory biology rather than robust testing of the devices themselves, as most have not been subjected to independent scientific studies. Therefore, there is a clear need for thorough testing of commercially available shark deterrents to provide the public with recommendations of their effectiveness. Using a modified stereo-camera system, we quantified behavioural interactions between white sharks (Carcharodon carcharias) and a baited target in the presence of a commercially available, personal electric shark deterrent (Shark Shield Freedom7™). The stereo-camera system enabled an accurate assessment of the behavioural responses of C. carcharias when encountering a non-lethal electric field many times stronger than what they would naturally experience. Upon their first observed encounter, all C. carcharias were repelled at a mean (± std. error) proximity of 131 (± 10.3) cm, which corresponded to a mean voltage gradient of 9.7 (± 0.9) V/m. With each subsequent encounter, their proximity decreased by an average of 11.6 cm, which corresponded to an increase in tolerance to the electric field by an average of 2.6 (± 0.5) V/m per encounter. Despite the increase in tolerance, sharks continued to be deterred from interacting for the duration of each trial when in the presence of an active Shark Shield™. Furthermore, the findings provide no support to the theory that electric deterrents attract sharks. The results of this study provide quantitative evidence of the effectiveness of a non-lethal electric shark deterrent, its influence on the behaviour of C. carcharias, and an accurate method for testing other shark deterrent technologies.en
dc.identifier.citationKempster RM, Egeberg CA, Hart NS, et al. How Close is too Close? The Effect of a Non-Lethal Electric Shark Deterrent on White Shark Behaviour. Patterson HM, ed. PLoS ONE. 2016;11(7):e0157717. doi:10.1371/journal.pone.0157717.en
dc.publisherPublic Library of Scienceen
dc.rightsCopyright © 2016 Kempster et alen
dc.rights.holderThe Authorsen
dc.titleHow Close is too Close? The Effect of a Non-Lethal Electric Shark Deterrent on White Shark Behaviouren
local.contributor.authorOrcidLookupHuveneers, Charlie:
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
4.56 MB
Adobe Portable Document Format
Published Version
License bundle
Now showing 1 - 1 of 1
No Thumbnail Available
2.73 KB
Item-specific license agreed upon to submission