Shark Shield - Electronic Shark Deterrent - Scientific Overview

Please also see the independant Scientifc Research on the effectiveness of Shark Shield here  

All chondrichthyans (sharks and rays) such as predatory sharks have highly sensitive electrical receptors called the “Ampullae of Lorenzini” located in their snouts. These tiny gel filled sacs sense electrical current from prey, but only at very close distances, typically less than one meter. They use these short range sensors when feeding or searching for food. They do not use electrical receptors to track animate objects over long distances – other senses such as audition and olfaction are the primary drivers. Scientists have discovered these receptors are an area where sharks are vulnerable, and that it is in fact possible to exploit this sensory system to our advantage, without harming the shark.
The Shark Shield electronic shark deterrent consists of two electrodes, which emit an electrical field that surrounds the user when the electrodes are submerged underwater simultaneously. The device emits a three-dimensional electronic pulse that interferes with a shark's sensory organ – the Ampullae of Lorenzini – a highly sensitive area located on the snout of all predatory sharks. The Ampullae of Lorenzini consists of a network of fluid filled sacs which serve as electrical receptors that are used to detect low-frequency electrical fields emitted by their prey within short distances. When the shark comes within a few meters from the Shark Shield, the strong electronic pulses emitted by the device cause the shark to experience muscle spasms and a high level of discomfort, which causes it to turn away from the electronic field, effectively repelling the shark and protecting the user.

In the video below we discuss how the electrical shark deterrent technology works and provide examples of the electircal field required to offer a level of protection against a shark attack. 

From testing, the closer the shark is to the Shark Shield field, the more spasms occur in the sharks’ snouts. This becomes intolerable and the shark then veers away, and usually doesn’t return.
A distinct advantage of the unique electrical wave-form is that it deters sharks and does no lasting harm to the shark. Once the shark is out of the affected area, it no longer feels the effect of the electrical wave form. The video below shows Ian "Shark" Gordon testing Shark Shield and the effectiveness of the technology on even the larges of sharks.

The original technology was released onto the market in 1995 by POD Holdings Ltd, a joint venture company partly owned by the Natal Sharks Board and the South African Government. In addition to being tested by National Military and other authorities, Shark Shield has been extensively tested to the highest standards by scientists and marine biologists over many years. You can review published test results here
Your questions weren’t answered here? Please see our FAQ’s page.