It is considered one of the few electrical devices on the market that has performed independent trials to determine its effectiveness[1][2] at deterring shark attacks,[3] Whilst it is noted the Shark Shield technology does not work in all situations,[1][4][2] modelling research from Flinders University in 2021 indicated that the proper use of personal electronic deterrents is an effective way to prevent future deaths and injuries, and estimated that these devices could save up to 1063 Australian lives along the coastline over 50 years.
All rights to the intellectual property were licensed to a South Australian-based company, SeaChange Technology Holdings, which developed various new application patents resulting in a commercial product line under the brand name Shark Shield in April 2002.
They do not use electrical receptors to track animate objects over long distances; other senses such as audition and olfaction are the primary drivers.
Research conducted by the South African National Space Agency in 2012 estimated the Shark Shield electrical field to be about 4–5 m in diameter.
[24][25] The range at which an electronic shark deterrent emits a field that is the equivalent of a prey-like stimulus (about 1–100 nV/cm) is much further than their short-range detection facilitates.
[30] In 2003, C F Smit, Department of Statistics, University of Pretoria, South Africa and V Peddemors, Department of Zoology, University of Durban-Westville, South Africa (Peddemors was employed by the Natal Sharks Board at the time) researched "Estimating the Probability of a Shark Attack when using an Electric Repellent".
In two series of tests of the SharkPOD, data were collected on the time needed to attack the bait, under power-off and power-on (active) conditions.
The stereo-camera system enabled an assessment of the behavioral responses of C.carcharias when encountering a non-lethal electric field many times stronger than what they would naturally experience.
[34][35] In reviewing the 2016 University of Western Australia[36] research, the Australian Geographic magazine published an article titled “Great White Shark Deterrent almost 100 Per Cent Effective”.
[38] In 2018 the New South Wales state government funded research conducted by Flinders University to test the Effectiveness of five personal shark deterrents for surfers.
Flinders tested five personal shark deterrents developed for surfers Ocean Guardian FREEDOM+ Surf, Rpela, SharkBanz bracelet, SharkBanz surf leash, and Chillax Wax) by comparing the percentage of baits taken, distance to the bait, number of passes, and whether a shark reaction could be observed.
The effectiveness of the deterrents was variable, with the FREEDOM+ Surf affecting shark behaviour the most and reducing the percentage of bait taken from 96% (relative to the control board) to 40%.
[39][40] There have been three known fatalities involving Shark Shield technology; Paul Buckland (2002), Peter Clarkson (2011) and Garry Johnson (2020).
The coroner concluded that the device was incorrectly worn and made the following recommendation; "I therefore recommend, pursuant to Section 25(2) of the Coroners Act, that commercial and recreational divers, when operating in waters where there is a risk of the presence of sharks, should wear a shark repellent device of the 'Shark Pod' or 'Shark Shield' type, provided that the equipment should be used in accordance with the manufacturer's instructions, and should be turned on for the entire duration of time in the water."
Peter Clarkson always wore a shark shield, which was confirmed by the presence of small floats from the tail of the device on the surface of water after the attack.
It is likely that the device was temporary turned off to reduce the risk of a shock whilst Johnson was securing a line to a rock on the sea floor.