Abstract: An Electronic Shark Deterrent provides protection from, and for, sharks and other aquatic creatures. Compact low power circuitry generates high voltage periodic pulse train bursts, disturbing the electroreceptors of the aquatic Elasmobranchi subclass. A train of thirty 33 us 250 Volt (V) electric pulses lasting one second is produced every six seconds. The device is fully portable, requiring no bulky activity impeding buoys, cords, or external power supplies. Advanced circuitry is compact enough to be worn on a watch sized band or attached to garments and recreation or safety equipment. The deterrent can be used in a fixed configuration to protect fish farms and vacation resort swimming areas. It can be affixed to offshore oil rigs and research stations to protect workers. The Electronic Shark Deterrent is compact and portable enough to be used on longlines, trawls and gillnets to reduce the numbers of endangered aquatic creatures unnecessarily destroyed as bycatch.