Circle Hooks

Fishery Type

Longline

Ocean Region

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

Target Species

Mahi, Swordfish, Tuna

Bycatch Species

Marine Mammals, Sea Turtles

In circle hooks, the pointed tip is bent back towards the shaft decreasing the spacing between the sharpened tip and shaft and changing the hook angle. The shape of the circle hook makes it harder for ETP bycatch to get hooked due to differences in jaw morphologies, but doesn’t impact catch rates in fish and can even in some cases increase catch rates. As a result, they are effective at decreasing ETP bycatch rates in longline fisheries, especially for sea turtles. In addition, in instances when the hook is swallowed, sea turtles are less likely to be gut hooked (hooked in the stomach or throat) which is a major cause of sea turtle post-release mortality in longline fisheries.