Abstract: Described is a chondrichthyan repelling system comprising at least one fin comprising at least one electrically conductive electrode for connection to an electrical signal generator. In use, the electrical signal generator generates electrical signals to the at least one electrode to thereby radiate an electrical field which repels chondrichthyans. Also disclosed are various fin designs incorporating one or more electrodes, and a watercraft having one or more fins as described. Various means of connecting the electrodes to the electrical signal generator are also described.

Abstract: A cord having two electrodes for generating a shark-repelling electromagnetic field about a user. The cord is connected to a field generator supported by the user, and in use, maintains contact with surrounding water, even if the user is out of the water.

Abstract: A device (10) for repelling selected aquatic creatures, such as sharks. The device consists of an electromagnetic field generator (21, 30) for generating an electromagnetic field (50) that repels sharks and is supported by a buoyant device (20). This provides a shark-free region about the device (10). Multiple devices can be connected together to form an array of repelling devices, thereby extending the shark-free region.

Abstract: A hull (10) for an aquatic vessel which provides a shark-repelling region about the vessel. The hull (10) includes two electrodes connected to an electromagnetic field signal generator, which in use, generates an electromagnetic field (40) about the vessel which repels sharks. The electrodes may be formed from the ends of an electrode cord (23), or may be formed from conductive (24, 25) plates (20, 21) mounted to, or integral with, the hull (10).