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Although effective in trials with captive loggerhead (Caretta caretta) and Kemp's ridley (Lepiochelys kempii) sea turtles, blue-dyed bait is not effective in reducing olive ridley (Lepidochelys olivacea) and green sea turtle (Chelonia mydas) bycatch in longline fisheries in Costa Rica.

18/0 circle hooks when compared with J hooks significantly reduce loggerhead (Caretta caretta) and leatherback (Dermocheles coriacea) sea turtle bycatch in Atlantic longline fisheries for pelagic swordfish (Xiphias gladius). Circle hooks also reduced the rate of hook ingestion by loggerhead sea turtles. The combination of circle hooks and mackerel (Scomber scombrus) bait was the most effective in reducing sea turtle bycatch and had no negative effect on swordfish catch. Loggerhead sea turtle (Caretta caretta) bycatch in the Atlantic longline fishery increased with an increase in total soak time. Soak time was insignificant for swordfish but it was significant for bigeye tuna (Thunnus obesus).

18/0 circle hooks when compared with J hooks significantly reduce loggerhead (Caretta caretta) and leatherback (Dermocheles coriacea) sea turtle bycatch in Atlantic longline fisheries for pelagic swordfish (Xiphias gladius). Circle hooks also reduced the rate of hook ingestion by loggerhead sea turtles. The combination of circle hooks and mackerel (Scomber scombrus) bait was the most effective in reducing sea turtle bycatch and had no negative effect on swordfish catch. Loggerhead sea turtle (Caretta caretta) bycatch in the Atlantic longline fishery increased with an increase in total soak time. Soak time was insignificant for swordfish but it was significant for bigeye tuna (Thunnus obesus).

18/0 circle hooks when compared with J hooks significantly reduce loggerhead (Caretta caretta) and leatherback (Dermocheles coriacea) sea turtle bycatch in Atlantic longline fisheries for pelagic swordfish (Xiphias gladius). Circle hooks also reduced the rate of hook ingestion by loggerhead sea turtles. The combination of circle hooks and mackerel (Scomber scombrus) bait was the most effective in reducing sea turtle bycatch and had no negative effect on swordfish catch. Loggerhead sea turtle (Caretta caretta) bycatch in the Atlantic longline fishery increased with an increase in total soak time. Soak time was insignificant for swordfish but it was significant for bigeye tuna (Thunnus obesus).

Fishing experiments were designed to test various gear modifications for the pelagic longline fishery in Hawaii, United States, to reduce sea turtle interactions. The experiments tested (1) daytime "stealth gear" (2) deep daytime setting, and (3) circle hooks combined with hook timers. Stealth gear and deep setting both caught significantly fewer swordfish compared to the control, although overall catch was reduced by 39% using stealth gear and was approximately similar to the control using deep setting. Neither gear configuration resulted in the take of any sea turtles (compared to one turtle in the control). Initial testing of hook timers with circle hooks resulted in the catch of two sea turtles. Circle hooks were also 40% as effective as J hooks at catching swordfish, and 94% as effective at catching tuna (by weight and value). 

A chain mat placed on Northwest Atlantic dredge gear eliminated bycatch of sea turtles: loggerhead (Caretta caretta), leatherback (Dermocheles coriacea), and green sea turtles (Chelonia mydas). The chain mat reduced catch by 6.71%.

Turtle excluder devices (TEDs) reduce sea turtle and non-target finfish (Atlantic croaker (Micropogonias undulateus), spot (Leiostomus exanthurus), sea catfish (Arius felis), and weakfish (Cynoscion regalis)) bycatch in the Gulf of Mexico prawn trawl fishery. Catch of targeted shrimp varied by location and TED configuration, but there was no significant difference in shrimp catch rates in 3 of the 4 TEDs when compared with a control net. One experimental TED in Texas (United States) exhibited a decrease in shrimp catch.

Circle hooks significantly reduce loggerhead (Caretta caretta) and leatherback (Dermocheles coriacea) sea turtle bycatch in Atlantic longline fisheries. Swordfish (Xiphias gladius) catch decreased when circle hooks were baited with squid but increased when baited with mackerel. Tuna catch increased when circle hooks were baited with squid but decreased when baited with mackerel.

Circle hooks (non-offset 16/0 and 18/0) did not significantly reduce the number of loggerhead sea turtles (Caretta caretta) caught in the Azores (Portugal) longline swordfish (Xiphias gladius) and blue shark (Prionace glauca) fishery when compared with non-offset and offset 9/0 J hooks. Use of circle hooks decreased the rate of throat hooking in loggerhead sea turtles (Caretta caretta). Circle hooks (non-offset 16/0 and 18/0) caught significantly more blue sharks than J hooks in the Azores longline swordfish and blue shark fisheries.