Fishery Type


Ocean Region

Indian Ocean, Eastern Pacific Ocean, Western Pacific Ocean, Northern Atlantic Ocean

Target Species

Mahi, Swordfish, Tuna

Bycatch Species

Sharks and Rays

Longline fisheries set out a long main line with hundreds to thousands of baited hooks attached on branch lines. Sharks and rays are attracted to baited hooks in addition to target species resulting in tens of millions caught as bycatch in longline fisheries each year. Sharkguard emits a powerful, shortrange electric pulse that deters sharks from baited hooks through interacting with electroreceptors around their head and mouth (Ampullae of Lorenzini). These electric pulses do not interfere with non-shark/ray target species since they do not have electroreceptors. Trials in July and August of 2021 in the commercial bluefin tuna fishery in the Mediterranean resulted in a 91% reduction in blue shark bycatch and a 71% reduction in pelagic stingray. The reduction in blue shark bycatch is particularly important since blue sharks are a major catch component of bluefin tuna fisheries.  Blue sharks were estimated to be 59% of all fish caught (including tunas) in the Chinese Atlantic bluefin tuna fishery from 2011 to 2018.


Fishtek Marine